Counter-tapered thermoplastic elastomer

Abstract

The counter-tapered diblock copolymer composition comprises a monovinyl aromatic monomer A polymerized with a conjugated diene monomer B to form a structure A-[A / B]. The [A / B] block is a copolymer of monomers A and B that is counter-tapered. This means that the ratio of B to A proximal to the A block is lower than the ratio of B to A distal to the A block. The [A / B] block preferably has a high vinyl content proximal to the A block as compared to the vinyl content distal to the A block. The diblock copolymer is preferably formed by partial coupling or with a polyfunctional initiator, providing a mixture of the diblock copolymer composition with a linear (A-[A / B])-X-([B / A]-A) structure and / or a coupled radial and / or multi-arm structure (A-[A / B])n-X (where X is the residue of a coupling agent or initiator). Asphalt and adhesive compositions are produced from the diblock copolymer composition and the above mixture.

Description

Technical Field

[0001] The present invention relates to a counter-tapered thermoplastic elastomer, a reinforcing material containing a polymer, and an article made of the reinforcing material.

Background Art

[0002] Anionic polymerization is a well-known technique for manufacturing elastomers. Commercially available polymers generally made by anionic polymerization processes include elastomers such as polybutadiene, polyisoprene, and styrene-diene rubber, and thermoplastic elastomers such as block copolymers of styrene, butadiene, and / or isoprene with various sizes and numbers of blocks.

[0003] Among the polymers prepared by anionic polymerization, commercially available styrene-diene rubbers such as tapered diblock copolymers of conjugated dienes and monovinyl aromatic monomers have long-term commercial importance due to their processing performance and unique properties in many applications. Special processing characteristics such as high extrusion suitability and excellent fluidity combined with mechanical properties such as high hardness, low shrinkage, and high abrasion resistance are a desirable polymer property balance for many high-productivity applications. Also, commercially available thermoplastic elastomers such as triblock copolymers of styrene, butadiene, and / or isoprene (SBn, SBS, SIS, SIBS, etc.) having various macro and microstructures are widely used due to their reinforcing performance and thermoplastic behavior in many applications.

[0004] Polymers prepared by anionic polymerization can be useful in themselves as tires and other industrial elastomers, adhesives, sealants, and coating agents. In addition, polymers prepared by anionic polymerization can be used to modify the characteristics of various materials such as asphalt, plastics, and rubbers. For example, polymers prepared by anionic polymerization can be used as compatibilizers and reinforcing agents for asphalt. However, many styrene / butadiene-based polymers prepared by anionic polymerization have insufficient compatibility and limited success in strengthening asphalt for applications in paving and roofing materials. Styrene / butadiene-based polymers, both linear and non-linear, are widely used for strengthening asphalt, but problems related to the dispersibility of polymers prepared by anionic polymerization in asphalt preparations and the resulting morphological stability of the polymer-modified asphalt formulations ultimately negatively impact the storage and long-term performance of the modified asphalt, such as the performance grade PG in the case of road paving and the high-temperature and low-temperature characteristics in the case of applications to roofing materials. Similar problems occur when anionic polymerization polymers are used in pressure-sensitive and non-pressure-sensitive hot melt and solvent-based adhesives for applications in tapes and labels, contact, and spraying.

[0005] Polymers prepared by anionic polymerization can be modified to improve the characteristics for their intended applications. Over the years, many modification routes have been developed. The most common modification routes include the following: molecular weight; molecular weight distribution; monomer composition; diene microstructure; monomer sequence length distribution; stereochemistry; monomer addition order and sequence; synthesizing polymers having linear, radial, comb, arm-like, branched, or hyperbranched structures by chain coupling through the reaction of polyfunctional species with living anions; and combinations of the above modifications. More sophisticated modification routes include the following: introducing chemical functionality by end-capping reactions or functional initiators; directly synthesizing polymers having linear, radial, comb, arm-like, branched, or hyperbranched structures by polymerization with polyfunctional initiators; hydrogenating residual double bonds; and combinations of the above modifications.

[0006] However, it is highly desirable to combine the unique processing characteristics of tapered diblock copolymers with the thermoplastic behavior of triblock copolymers in a manner that improves the balance between processability and reinforcement performance in many applications. Further, it is desirable to develop elastomeric compositions and find anionic polymerization-based routes for preparing those compositions to combine the best properties of the commercially available polymers, which are typically impaired among the polymer characteristics. Therefore, it would be desirable to develop a method for producing an elastomeric composition that is more processable, dispersible, compatible with a wide variety of materials including asphalt, adhesives, and sealant components and other substrates, and suitable for meeting the reinforcement requirements of a wide range of applications such as road paving, roofing materials, roof boards, waterproof membranes, adhesive tapes and labels, contact and spray adhesives, and sealants by preparing polymers by anionic polymerization.

[0007] Surprisingly, in this specification, a novel counter-tapered thermoplastic elastomer composition has been found that achieves a better balance between processability and reinforcement performance for application to various asphalts, adhesives, and sealants. The novel counter-tapered thermoplastic elastomer composition provides, for the applications mentioned above, processability advantages such as short dispersion time, higher compatibility, low mixing temperature, low viscosity, excellent storage stability, etc., and better reinforcement advantages such as high elastic response, wide range of performance grades, high adhesiveness, higher filler loading capacity, excellent adhesion strength and shear resistance, and better compromise between high-temperature and low-temperature properties.

Summary of the Invention

[0008] The present invention provides a counter-tapered thermoplastic elastomer composition, a method for producing a polymer, a polymer blend and mixture containing the polymer, an asphalt and adhesive composition containing the polymer, a reinforcing material containing the polymer, and an article made of the reinforcing material.

[0009] The present invention provides a counter-tapered diblock copolymer composition. The counter-tapered diblock copolymer composition includes units of at least one monovinyl aromatic monomer A polymerized with units of at least one conjugated diene monomer B so as to form a structure A-[A / B], the A block includes a homopolymer of monovinyl aromatic monomer units, the [A / B] block is a copolymer of monovinyl aromatic monomer units and conjugated diene monomer units, and the [A / B] block is counter-tapered such that the ratio of B to A proximal to the A block is lower than the ratio of B to A distal to the A block. The counter-tapered diblock A-[A / B] copolymer is further defined as preferably having a vinyl content of at least 15 weight percent based on the amount of conjugated diene units in the diblock copolymer. The [A / B] block is further defined as preferably having a higher vinyl content proximal to the A block than distal to the A block.

[0010] The present invention also provides a counter-tapered thermoplastic elastomer (CTTE) composition. The CTTE composition includes units of at least one monovinyl aromatic monomer A and units of at least one conjugated diene monomer B, and has a linear structure (A-[A / B])-X-([B / A]-A) and / or a coupled radial and / or multi-arm structure (A-[A / B])n-X, where X is the residue of a coupling agent, n is an integer from 2 to about 30. The CTTE composition has an outer block and / or a terminal block A that is a polymer of monovinyl aromatic monomer units A. The CTTE composition has an intermediate block that is a copolymer of monovinyl aromatic monomer units A and conjugated diene monomer units B. The intermediate block has a central region between terminal regions, the B / A ratio is higher in the central region than in the terminal regions, and the vinyl content is preferably lower in the central region than in the terminal regions.

[0011] One embodiment of the present invention is a mixture of the counter-tapered diblock copolymer composition and the CTTE composition. The mixture can be achieved by partially coupling the counter-tapered diblock copolymer composition or by selecting an appropriate initiator. The present invention provides a counter-tapered thermoplastic elastomer (CTTE) composition including units of at least one monovinyl aromatic monomer A and units of at least one conjugated diene monomer B using an initiator route. The composition has a structure X-([A / B]-A) and / or a linear structure (A-[B / A])-X-([A / B]-A) and / or a coupled radial and / or multi-arm structure X-([A / B]-A)n, where X is the residue of a monofunctional and / or polyfunctional initiator, n is an integer from 1 to about 30. The CTTE composition has an outer block and / or a terminal block A that is a polymer of monovinyl aromatic monomer units A. The CTTE composition has an intermediate block that is a copolymer of monovinyl aromatic monomer units A and conjugated diene monomer units B. The intermediate block has a central region between terminal regions, the B / A ratio is lower in the central region than in the terminal regions, and the vinyl content is higher in the central region than in the terminal regions.

[0012] The present invention provides a counter-tapered thermoplastic elastomer (CTTE) composition comprising a counter-tapered diblock A-[A / B] copolymer containing at least one monovinyl aromatic monomer A and at least one conjugated diene monomer B, wherein the [A / B] block is counter-tapered such that the ratio of B to A proximal to the A block is lower than the ratio of B to A distal to the A block, the counter-tapered diblock A-[A / B] copolymer has a vinyl content of at least 15 weight percent based on the amount of conjugated diene units in the diblock copolymer, and preferably has a block copolymer produced by partially coupling the counter-tapered diblock A-[A / B] copolymer with a coupling agent, the block copolymer having a linear structure (A-[A / B])-X-([B / A]-A) and / or a coupled radial and / or multi-arm structure (A-[A / B])n-X, where X is the residue of the coupling agent and n is an integer from 2 to about 30, the CTTE composition having an outer block and / or end block A that is a polymer of monovinyl aromatic monomer units A, the CTTE composition having an intermediate block that is a copolymer of monovinyl aromatic monomer units A and conjugated diene monomer units B, the intermediate block having a central region between end regions, the B / A ratio being higher in the central region than in the end regions, and the vinyl content being lower in the central region than in the end regions.

[0013] In another embodiment, the present invention provides a novel counter-tapered thermoplastic elastomer composition made from a conjugated diene monomer (B) and a monovinyl aromatic monomer (A). The counter-tapered thermoplastic elastomer composition has (a) a counter-tapered diblock A-[A / B] copolymer, and (b) a block copolymer selected from the group consisting of a linear triblock copolymer, a multi-arm coupling block copolymer, and mixtures thereof, and (c) the ratio of (a) to (b) in the counter-tapered thermoplastic elastomer composition is from about 1:5 to about 5:1. The counter-tapered thermoplastic elastomer composition achieves a better balance of processability and reinforcement performance for various applications in asphalt, adhesives, and sealants. The novel counter-tapered thermoplastic elastomer composition provides, for the applications mentioned above, processability advantages such as short dispersion time, higher compatibility, low mixing temperature, low viscosity, excellent storage stability, etc., and better reinforcement advantages such as high elastic response, wide range of performance grades, high adhesiveness, higher filler loading capacity, excellent adhesion strength and shear resistance, and better compromise between high temperature and low temperature properties. Due to these processability and reinforcement advantages, the counter-tapered thermoplastic elastomer composition preferably meets the requirements of a wide range of applications such as road paving, roofing materials, roof boards, waterproof membranes, coatings, adhesive tapes and labels, contact and spray adhesives, and sealants.

[0014] The counter-tapered thermoplastic elastomer composition according to the present invention preferably (a) A counter-tapered diblock A-[A / B] copolymer comprising at least one conjugated diene monomer and at least one monovinyl aromatic monomer, wherein the diblock copolymer preferably has a peak molecular weight from 20,000 to 250,000, a monovinyl aromatic homopolymer block A having a peak molecular weight of preferably at least 5,000, and a counter-tapered copolymer block [A / B] having a vinyl content of preferably at least 15 weight percent based on the amount of conjugated diene units in the diblock copolymer; and (b) A block copolymer comprising at least one conjugated diene monomer and at least one monovinyl aromatic monomer, wherein the block copolymer preferably has at least two homopolymer blocks of the monovinyl aromatic monomer and at least one copolymer block of the monovinyl aromatic monomer and the conjugated diene monomer, and the block copolymer is selected from the group consisting of a linear triblock copolymer having a peak molecular weight of preferably at least about 1.5 times the peak molecular weight of the counter-tapered diblock copolymer described in (a), a multi-arm coupling block copolymer having a peak molecular weight of at least about 2.5 times the peak molecular weight of the counter-tapered diblock copolymer described in (a), and mixtures thereof, and each block copolymer preferably has a monovinyl aromatic homopolymer block A having a peak molecular weight of at least 5,000 and a counter-tapered copolymer block [A / B] having a vinyl content of preferably at least 15 weight percent based on the amount of conjugated diene units in the block copolymer, preferably, (c) The ratio of (a) to (b) in the counter-tapered thermoplastic elastomer composition is from about 1:5 to about 5:1.

[0015] The counter-tapered thermoplastic elastomer composition according to the present invention has both a counter-tapered diblock A-[A / B] copolymer and a block copolymer formed by a partial coupling or a multifunctional initiator, and preferably, (a) a weight average molecular weight of from about 30,000 to about 500,000 g / mol; (b) a total amount of monovinyl aromatic monomers in the counter-tapered thermoplastic elastomer composition of from about 10 weight percent to about 55 weight percent; and (c) a total vinyl content of from about 15 weight percent to about 90 weight percent based on the total amount of conjugated dienes in the counter-tapered thermoplastic elastomer composition having.

[0016] A further embodiment of the present invention is a method of making a counter-tapered thermoplastic elastomer composition, comprising adding a solvent, a polarity modifier or a combination of polarity modifiers, and a monovinyl aromatic monomer to a reactor to form an initial reaction mixture, wherein the amount of the polarity modifier in the initial reaction mixture is less than 10% by weight; adding an organolithium initiator compound to the reactor and anionically polymerizing the monomer to form a monovinyl aromatic homopolymer block A having a peak molecular weight of preferably at least 5,000; adding additional monovinyl aromatic monomer and simultaneously starting the feeding of a conjugated diene monomer to the reactor at a predetermined feeding rate over a predetermined time, provided that the conjugated diene monomer is preferably added at a lower rate than the monovinyl aromatic monomer, and copolymerizing to form a counter-tapered copolymer block [A / B] having a vinyl content of preferably at least 15 weight percent based on the amount of conjugated diene units in the diblock copolymer, thereby obtaining a counter-tapered diblock A-[A / B] copolymer having a peak molecular weight of preferably 20,000 to 250,000; and adding a coupling agent or a combination of coupling agents to partially couple the counter-tapered diblock A-[A / B] copolymer to form a block copolymer which is either a linear triblock copolymer, a multi-arm coupling block copolymer, or a mixture thereof, wherein the solvent, the polarity modifier, the conjugated diene monomer, and the monovinyl aromatic monomer constitute the total reaction mixture, the amount of the polarity modifier is less than 5% by weight of the total reaction mixture, the peak molecular weight of the linear triblock copolymer is preferably at least about 1.5 times the peak molecular weight of the counter-tapered diblock A-[A / B] copolymer, the peak molecular weight of the multi-arm coupling block copolymer is preferably at least about 2.5 times the peak molecular weight of the counter-tapered diblock A-[A / B], and the ratio of the counter-tapered diblock A-[A / B] copolymer to the block copolymer in the counter-tapered thermoplastic elastomer composition is preferably from about 1:5 to about 5:1.

[0017] The present invention provides a composition and an article made of a counter-tapered thermoplastic elastomer composition, a reinforcing material made of a mixture of a counter-tapered thermoplastic elastomer composition and a material to be reinforced, and an article made of the reinforcing material. The present invention provides a novel counter-tapered thermoplastic elastomer composition, a formulation with other block copolymers having enhanced adhesion to a specific substrate, and an article made of a material with enhanced adhesion. The counter-tapered thermoplastic elastomer composition of the present invention achieves a better balance between processability and reinforcing performance for application to various asphalts, adhesives, and sealants. The counter-tapered thermoplastic elastomer composition provides these applications with processability advantages such as short dispersion time, higher compatibility, lower mixing temperature, lower viscosity, excellent storage stability, etc., and better reinforcing advantages such as higher elastic response, wide range of performance grades, higher adhesion, higher filler loading capacity, excellent adhesion strength and shear resistance, and better compromise between high-temperature and low-temperature properties. Due to these processability and reinforcing advantages, the novel counter-tapered thermoplastic elastomer composition suitably meets the requirements of a wide range of applications such as road paving, roofing materials, roof boards, waterproof membranes, adhesive tapes and labels, contact and spray adhesives, and sealants.

[0018] One embodiment of the present invention is an asphalt and / or bitumen composition comprising asphalt and / or bitumen and a first counter-tapered thermoplastic elastomer (first CTTE) composition, wherein the asphalt and / or bitumen composition comprises 0.5 to 25 weight percent of the first CTTE composition, and the first CTTE composition comprises units of at least one monovinyl aromatic monomer A polymerized with units of at least one conjugated diene monomer B so as to form a counter-tapered diblock A-[A / B] copolymer, the A block comprises a polymer of monovinyl aromatic monomer units, the [A / B] block is a copolymer of monovinyl aromatic monomer units and conjugated diene monomer units, and the [A / B] block is counter-tapered such that the ratio of B to A proximal to the A block is lower than the ratio of B to A distal to the A block. The total amount of units of the conjugated diene monomer B is preferably more than 55% by weight of the first CTTE composition, and in the counter-tapered diblock A-[A / B] copolymer, the vinyl content proximal to the A block is preferably higher than the vinyl content distal to the A block. The [A / B] block of the first CTTE composition preferably comprises 2 to 40% by weight of the monovinyl aromatic monomer A and preferably 60 to 98% by weight of the conjugated diene monomer B.

[0019] The asphalt and / or bitumen composition preferably further comprises a second counter-tapered thermoplastic elastomer (second CTTE) composition. The second CTTE composition comprises units of at least one monovinyl aromatic monomer A and units of at least one conjugated diene monomer B, and has a linear structure (A-[A / B])-X-([B / A]-A) and / or a coupled radial and / or multi-arm structure (A-[A / B])n-X, where X is the residue of either a coupling agent or a polyfunctional initiator, n is an integer from 2 to 30, the second CTTE composition has an outer block and / or end block A that is a polymer of monovinyl aromatic monomer units A, the second CTTE composition has an intermediate block that is a copolymer of monovinyl aromatic monomer units A and conjugated diene monomer units B, the intermediate block has a central region between end regions, and the B / A ratio is higher in the central region than in the end regions.

[0020] A further embodiment of the invention is an asphalt and / or bitumen composition comprising asphalt and / or bitumen and a second CTTE composition, the asphalt and / or bitumen composition comprising from 0.5 to 25 weight percent of the second CTTE composition and essentially no or very little of the first CTTE composition, which can be achieved by complete or nearly complete coupling of the first CTTE composition.

[0021] Another embodiment of the present invention is an adhesive composition. The adhesive composition includes the first CTTE composition and a tackifier resin, and preferably further includes at least one additive selected from the group consisting of a plasticizer, a solvent, a coupling agent, a crosslinking agent, a photoinitiator, and an antioxidant. The adhesive composition preferably further includes the second CTTE composition. Another embodiment of the present invention is an adhesive composition including the second CTTE composition and a tackifier resin, and preferably further includes at least one additive selected from the group consisting of a plasticizer, a solvent, a coupling agent, a crosslinking agent, a photoinitiator, and an antioxidant. The adhesive composition includes 0.5 to 50 weight percent of the second CTTE composition and essentially no or very little of the first CTTE composition, which can be achieved by complete or nearly complete coupling of the first CTTE composition.

Brief Description of the Drawings

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[0023] The present invention provides a counter - tapered thermoplastic elastomer composition, a method of producing a polymer, a polymer blend and mixture containing the above polymer, a reinforcing material containing the above polymer, and an article made of the above reinforcing material.

[0024] One aspect of the present invention provides a novel counter-tapered thermoplastic elastomer composition made of a conjugated diene monomer (B) and a monovinyl aromatic monomer (A). The novel counter-tapered thermoplastic elastomer composition has (a) a counter-tapered diblock A-[A / B] copolymer, and (b) a block copolymer selected from the group consisting of a linear triblock copolymer, a multi-arm coupling block copolymer, and mixtures thereof, and (c) the ratio of (a) to (b) in the counter-tapered thermoplastic elastomer composition is from about 1:5 to about 5:1. The novel counter-tapered thermoplastic elastomer composition achieves a better balance between processability and reinforcement performance for various applications in asphalt, adhesives, and sealants. The novel counter-tapered thermoplastic elastomer composition provides advantages in processability such as short dispersion time, low mixing temperature, low viscosity, excellent storage stability, etc. and better reinforcement advantages such as high elastic response, wide range of performance grades, high adhesiveness, higher filler loading capacity, and better compromise between high-temperature and low-temperature properties for the applications mentioned above. These processability and reinforcement advantages enable the novel counter-tapered thermoplastic elastomer composition to preferably meet the requirements of a wide range of applications such as road paving, roofing materials, roof boards, waterproof membranes, adhesive tapes and labels, contact and spray adhesives, and sealants.

[0025] The novel counter-tapered thermoplastic elastomer composition according to the present invention comprises (a) a counter-tapered diblock A-[A / B] copolymer comprising at least one conjugated diene monomer and at least one monovinyl aromatic monomer, the diblock copolymer having a peak molecular weight from 20,000 to 250,000, a monovinyl aromatic homopolymer block A having a peak molecular weight of at least 5,000, and a counter-tapered copolymer block [A / B] having a vinyl content of at least 15 weight percent based on the amount of conjugated diene units in the diblock copolymer, the counter-tapered diblock A-[A / B] copolymer being further characterized thereby; and (b) A block copolymer comprising at least one conjugated diene monomer and at least one monovinyl aromatic monomer, the block copolymer being further characterized by having at least two homopolymer blocks of the monovinyl aromatic monomer and at least one copolymer block of the monovinyl aromatic monomer and the conjugated diene monomer, the block copolymer being selected from the group consisting of a linear triblock copolymer having a peak molecular weight of at least about 1.5 times the peak molecular weight of the counter-tapered diblock copolymer described in (a), a multi-arm coupling block copolymer having a peak molecular weight of at least about 2.5 times the peak molecular weight of the counter-tapered diblock copolymer described in (a), and mixtures thereof, each block copolymer comprising a monovinyl aromatic homopolymer block A having a peak molecular weight of at least 5,000 and a counter-tapered copolymer block [A / B] having a vinyl content of at least 15 weight percent based on the amount of conjugated diene units in the block copolymer. (c) The ratio of (a) to (b) in the counter-tapered thermoplastic elastomer composition is from about 1:5 to about 5:1.

[0026] The novel counter-tapered thermoplastic elastomer composition according to the present invention is (a) the weight average molecular weight of the counter-tapered thermoplastic elastomer composition is from about 30,000 to about 500,000 g / mol, (b) the total amount of the monovinyl aromatic monomer in the counter-tapered thermoplastic elastomer composition is from about 10 weight percent to about 55 weight percent, and (c) the total vinyl constitutional content is characterized by being from about 15 weight percent to about 90 weight percent based on the total amount of conjugated diene in the counter-tapered thermoplastic elastomer composition.

[0027] Polymers prepared by anionic polymerization include thermoplastics, elastomers, and thermoplastic-elastomer polymers. The polymer may be a homopolymer or copolymer, including tapered, random, and block copolymers. Among the polymers prepared by anionic polymerization, tapered diblock copolymers of conjugated dienes and monovinyl aromatic monomers have had commercial importance over the long term due to their performance and unique properties in numerous applications. Special processing characteristics such as high extrusion suitability and excellent fluidity, combined with mechanical properties such as high hardness, low shrinkage, and high abrasion resistance, are a desirable polymer property balance for many high-productivity applications. Also, commercially available thermoplastic elastomers such as triblock copolymers of styrene, butadiene, and / or isoprene (SBn, SBS, SIS, SIBS, etc.) having various macro- and microstructures are widely used due to their enhanced performance and thermoplastic behavior in many applications. However, it is still highly desirable to combine the unique processing characteristics of tapered diblock copolymers with the thermoplastic behavior of triblock copolymers in a manner that improves the balance between processability and enhanced performance in many applications.

[0028] The anionic lithium-initiated copolymerization of conjugated dienes and monovinyl aromatic monomers in hydrocarbon solvents in the absence of polar additives produces an interesting type of structure with compositional heterogeneity along the copolymer chain. This is generally known as a tapered, gradual, gradient diblock copolymer structure. Despite the similar stability of the carbanionic chain ends corresponding to the conjugated diene (1) and monovinyl aromatic (2) monomers, a relatively large difference (i.e., r1 > 10 and r2 < 0.1) is observed between the monomer reactivity ratios. Contrary to the observation that the homopolymerization of monovinyl aromatic monomers is faster than that of conjugated diene monomers, at the initial stage of copolymerization, the less reactive conjugated diene monomers are preferentially incorporated into the copolymer chain until they are almost completely consumed, forming a diene-rich tapered block B with a gradually changing composition. Subsequently, at the final stage, most of the monovinyl aromatic monomers form the terminal polystyrene block A.

[0029] B-(B / A)-A Furthermore, during copolymerization in a hydrocarbon solvent in the absence of a polarity additive, a characteristic intermediate stage occurs in which a small, sharp and steep interfacial phase-(B / A)- with a sudden change in composition is formed, and this interfacial phase acts as a transition part within the copolymer chain between two large A blocks and B blocks. The presence of this small interfacial phase results in the melt viscosity of the tapered diblock copolymer being lower than that of a pure diblock copolymer of the same composition and molecular weight, weakening the intra-chain and inter-chain repulsions and enhancing the mixing between dissimilar adjacent blocks. The anionic lithium-initiated copolymerization of conjugated dienes and monovinyl aromatic monomers under the above conditions behaves statistically such that the monomer units tend to be randomly arranged (i.e., r1r2 = about 0.5) mainly due to the large difference in monomer reactivity ratios, and both block B and the interfacial phase-(B / A)- exhibit compositional fluctuations along the copolymer chain that are positively dependent on the instantaneous relative monomer concentrations. Thus, an initially relatively low concentration of monovinyl aromatic monomer is incorporated into the diene-rich tapered block B mostly randomly and mainly as isolated aromatic units. In contrast, an intermediate relatively high concentration of monovinyl aromatic monomer is incorporated statistically and mainly into the small, sharp and steep interfacial phase-(B / A)- as long aromatic sequences that should rapidly become aromatic-rich segments, together with residual isolated diene units.

[0030] The copolymerization of conjugated dienes and monovinyl aromatic monomers with alkyllithium in the absence of a polar additive typically results in a tapered diblock copolymer with a low vinyl content (1,2-diene microstructure). The polar additive acts simultaneously as a randomizing agent and a microstructure regulator during the copolymerization of conjugated dienes and monovinyl aromatic monomers with an alkyllithium initiator. The relatively large difference between the monomer reactivity ratios decreases as the polar additive concentration increases, whereby the copolymerization behavior gradually changes from statistical to random, and the monomer sequence length distribution converts from a tapered diblock to a random diblock and then to a completely random copolymer structure. This randomizing effect is typically accompanied by a corresponding modifying effect of increasing the vinyl content. Both effects are positively dependent on the polar additive concentration, and furthermore, the modifying effect is inversely dependent on the polymerization temperature, but the scope and specific behavior of each effect depend particularly on the type and specific properties of the polar additive. Combining polar additives makes it possible to overcome some obstacles and obtain a synergistic or desired differentiating effect on the monomer sequence length distribution and / or the 1,2-diene microstructure.

[0031] By controlling the monomer addition order, polymerization sequence, feed rate, and feed composition; the combination, type, concentration, addition order, and feed rate of polar additives; the polymerization temperature behavior and conditions; and the relative block size and molecular weight, the design of a novel counter-tapered thermoplastic elastomer composition can be made to include the features and characteristics according to the present invention, namely (a) a counter-tapered diblock A-[A / B] copolymer; and (b) a block copolymer selected from the group consisting of linear triblock copolymers, multi-arm coupling block copolymers, and mixtures thereof, and (c) the ratio of (a) to (b) in the counter-tapered thermoplastic elastomer composition can be adjusted to be from about 1:5 to about 5:1. Such design features are suitable properties for achieving the desired overall application performance in formulations with a wide variety of materials and other substrates, including asphalt, adhesives, and sealant components, rubbers, and plastics. The desired overall application performance is a balance between maximized processing characteristics such as low melt viscosity, high dispersibility, high compatibility, high miscibility, and / or high adhesiveness, as well as good elastic and thermoplastic properties. Specific applications for which the novel counter-tapered thermoplastic elastomer composition of the present invention is well-suited include asphalt strengtheners, modifiers, and morphology stabilizers. Other suitable applications include use as compatibilizers, viscosity regulators, flow regulators, processing aids, rheology control agents, and impact regulators for plastics and plastic formulations, mixtures, and composites. Also, the novel counter-tapered thermoplastic elastomer composition can be designed to have adjusted characteristics to provide a highly processable adhesive having optimal adhesiveness to polar substrates useful for typical adhesives and sealant applications. The novel counter-tapered thermoplastic elastomer composition achieves a better balance between processability and strengthening performance for application to various asphalts, adhesives, and sealants.The novel counter-tapered thermoplastic elastomer composition provides the advantages of easy processability such as short dispersion time, low mixing temperature, low viscosity, excellent storage stability, etc. for the applications mentioned above, and better reinforcement advantages such as high elastic response, wide range of performance grades, high adhesiveness, higher filler loading capacity, and better compromise between high-temperature and low-temperature properties. Due to these processability and reinforcement advantages, the novel counter-tapered thermoplastic elastomer composition preferably meets the requirements of a wide range of applications such as road paving, roofing materials, roof boards, waterproof membranes, adhesive tapes and labels, contact and spray adhesives, and sealants.

[0032] Another aspect of the present invention is a method for producing a counter-tapered thermoplastic elastomer composition, comprising reacting at least one conjugated diene monomer and at least one monovinyl aromatic monomer in the presence of a suitable polarity regulator or a combination of polarity regulators and under anionic polymerization conditions; and (a) a counter-tapered diblock A-[A / B] copolymer comprising at least one conjugated diene monomer and at least one monovinyl aromatic monomer, the diblock copolymer having a peak molecular weight from 20,000 to 250,000, a monovinyl aromatic homopolymer block A having a peak molecular weight of at least 5,000, and a counter-tapered copolymer block [A / B] having a vinyl content of at least 15 weight percent based on the amount of conjugated diene units in the diblock copolymer, further characterized by a counter-tapered diblock A-[A / B] copolymer; and (b) A block copolymer comprising at least one conjugated diene monomer and at least one monovinyl aromatic monomer, the block copolymer being further characterized by having at least two homopolymer blocks of the monovinyl aromatic monomer and at least one copolymer block of the monovinyl aromatic monomer and the conjugated diene monomer, the block copolymer being selected from the group consisting of a linear triblock copolymer having a peak molecular weight of at least about 1.5 times the peak molecular weight of the counter-tapered diblock copolymer described in (a), a multi-arm coupling block copolymer having a peak molecular weight of at least about 2.5 times the peak molecular weight of the counter-tapered diblock copolymer described in (a), and mixtures thereof, each block copolymer comprising a monovinyl aromatic homopolymer block A having a peak molecular weight of at least 5,000, and a counter-tapered copolymer block [A / B] having a vinyl content of at least 15 weight percent based on the amount of conjugated diene units in the block copolymer. (c) A method is provided that includes forming a composition of the present invention in which the ratio of (a) to (b) in the counter-tapered thermoplastic elastomer composition is from about 1:5 to about 5:1.

[0033] A further embodiment of the present invention is a method of making a counter-tapered thermoplastic elastomer composition, comprising adding a solvent, a polarity modifier or a combination of polarity modifiers, and a monovinyl aromatic monomer to a reactor to form an initial reaction mixture, wherein the amount of the polarity modifier in the initial reaction mixture is less than 10 wt%; adding an organolithium initiator compound to the reactor and anionically polymerizing the monomer to form a monovinyl aromatic homopolymer block A having a peak molecular weight of at least 5,000; adding additional monovinyl aromatic monomer and simultaneously starting the feed of a conjugated diene monomer to the reactor at a predetermined feed rate over a predetermined time and copolymerizing to form a counter-tapered copolymer block [A / B] having a vinyl content of at least 15 weight percent based on the amount of conjugated diene units in the diblock copolymer, to obtain a counter-tapered diblock A-[A / B] copolymer having a peak molecular weight from 20,000 to 250,000; and adding a coupling agent or a combination of coupling agents to partially couple the counter-tapered diblock A-[A / B] copolymer to form a block copolymer which is either a linear triblock copolymer, a multi-arm coupling block copolymer, or a mixture thereof, wherein the solvent, the polarity modifier, the conjugated diene monomer, and the monovinyl aromatic monomer constitute the total reaction mixture, the amount of the polarity modifier is less than 5 wt% of the total reaction mixture, the peak molecular weight of the linear triblock copolymer is at least about 1.5 times the peak molecular weight of the counter-tapered diblock A-[A / B] copolymer, the peak molecular weight of the multi-arm coupling block copolymer is at least about 2.5 times the peak molecular weight of the counter-tapered diblock A-[A / B] copolymer, and the ratio of the counter-tapered diblock A-[A / B] copolymer to the block copolymer is from about 1:5 to about 5:1 in the counter-tapered thermoplastic elastomer composition.

[0034] The present invention also provides a method for preparing a novel counter-tapered thermoplastic elastomer composition, comprising reacting at least one conjugated diene monomer (B) and at least one monovinyl aromatic monomer (A) in the presence of a suitable polar additive or combination of polar additives and under anionic polymerization conditions such that a counter-tapered diblock copolymer A-[A / B] is formed, and then adding a suitable coupling agent to form a block copolymer exhibiting thermoplastic behavior, and finally obtaining a counter-tapered thermoplastic elastomer composition. Thus, in a preferred embodiment of the present invention, the counter-tapered diblock A-[A / B] copolymer is polymerized sequentially to independently manipulate the size, composition, and microstructure of the desired counter-tapered copolymer block [A / B]. Manipulation includes controlling the monovinyl aromatic monomer sequence length and the conjugated diene monomer vinyl distribution (1,2-diene microstructure). Also, sequential polymerization allows adjustment of the relative size of the monovinyl aromatic homopolymer A and the relative order of the blocks in the copolymer, and thus, to form the desired counter-tapered diblock A-[A / B] copolymer, the monovinyl aromatic homopolymer block A is first polymerized adjacent to the counter-tapered copolymer block [A / B].

[0035] The vinyl aromatic monomer sequence length and the conjugated diene monomer vinyl distribution of the counter-tapered copolymer block [A / B] can be manipulated by controlling the temperature profile of the polymerization. This polymerization step can proceed either in isothermal mode over a pre-established residence time or in pseudo-adiabatic mode up to the peak temperature. Using the isothermal mode allows for manipulating a uniform vinyl distribution along the copolymer chain and achieving a maximized vinyl content with respect to the amount of polar additive added and the temperature setting of the polymerization mixture. As a result, the vinyl aromatic monomer sequence length depends only on the instantaneous relative monomer concentration. Using the pseudo-adiabatic mode allows for manipulating a vinyl distribution gradient along the copolymer chain, so the vinyl aromatic monomer sequence length depends not only on the instantaneous relative monomer concentration but also on the actual temperature profile. The vinyl distribution gradient depends on not only the controlled temperature profile but also the initial and final temperatures of the polymerization mixture. The counter-tapered copolymer block [A / B] is engineered to adjust the controlled vinyl distribution that contributes to maximizing processing characteristics by increasing flow and reducing melt viscosity, as well as to optimize compatibility with the materials, components, and / or substrates used in the desired application.

[0036] In another embodiment of the present invention, the counter-tapered copolymer block [A / B] is a statistical distribution copolymer block of at least one conjugated diene monomer (B) and at least one monovinyl aromatic monomer (A), and the statistical distribution means that the sequence distribution of the monomer units follows a known statistical law. The counter-tapered copolymer block [A / B] has a microstructure with a gradually changing composition, which mainly depends on the amount of suitable polar additives added to the polymerization mixture and the temperature profile. Alternatively or in addition, the counter-tapered copolymer block [A / B] can be prepared by adding a conjugated diene monomer to the polymerization mixture at a controlled feed rate during the polymerization of the monovinyl aromatic monomer. The dosing of the conjugated diene monomer into the reactor at a predetermined feed rate over a predetermined time is carried out in such a way as to control the relative monomer concentration at that instant. This polymerization step can be carried out either in an isothermal mode over a pre-established residence time or in a pseudo-adiabatic mode up to the peak temperature. The counter-tapered copolymer block [A / B] is enlarged relative to the small interfacial phase-(B / A)-typical of copolymerization in the absence of polar additives. The enlarged counter-tapered copolymer block [A / B] is manipulated to adjust its relative size with respect to the adjacent monovinyl aromatic homopolymer block A to contribute to minimizing repulsion, maximizing compatibility, promoting interfacial mixing, and improving toughness and fracture strength. The optimal counter-tapered copolymer block [A / B] is the one incorporated into the counter-tapered thermoplastic elastomer composition, providing the best balance of processability and strengthening performance for each application. Those skilled in the art will understand that there are differences in the characteristics, properties, and applicability of these different counter-tapered thermoplastic elastomer compositions.

[0037] In a further embodiment of the present invention, each A block is a monovinyl aromatic homopolymer block of at least one monovinyl aromatic monomer. Each A block is manipulated to adjust its relative size with respect to the counter-tapered copolymer block [A / B] to contribute to achieving the desired application performance.

[0038] The novel counter-tapered thermoplastic elastomer composition used in the present invention typically has a weight average molecular weight ranging from about 30,000 to about 500,000 g / mol. This range preferably includes a monovinyl aromatic homopolymer block A having a peak molecular weight of at least about 8,000 g / mol, a counter-tapered diblock A-[A / B] copolymer preferably having a peak molecular weight ranging from about 20,000 to 250,000 g / mol, and a multi-arm coupling block copolymer preferably having a peak molecular weight ranging from about 40,000 to 750,000 g / mol. Throughout this disclosure, the cited molecular weights are measured using gel permeation chromatography based on ASTM D 3536 using linear polystyrene standards. The composition of the vinyl aromatic monomer in the counter-tapered thermoplastic elastomer composition preferably ranges from about 10 to about 85 weight percent, more preferably from about 10 to about 70 weight percent, and even more preferably from about 10 to 55 weight percent. The vinyl content of the novel counter-tapered thermoplastic elastomer composition may preferably range from about 15 to about 90 weight percent, more preferably from about 15 to about 85 weight percent, and even more preferably from about 15 to 80 weight percent, based on the total amount of conjugated diene monomers in the counter-tapered copolymer block [A / B]. The present invention is not limited to counter-tapered thermoplastic elastomer compositions that fall within the preferred molecular weight, composition, and vinyl configuration ranges.

[0039] Examples of counter-tapered thermoplastic elastomer compositions that can be made from anionic polymerizable monomers include, but are not limited to, elastomers and thermoplastic elastomers made from block copolymers or terpolymers of styrene (S), butadiene (B), and / or isoprene (I) with various block sizes and numbers. Examples of such elastomers and thermoplastic elastomers include the following: S-[B / S]m, S-[B / S]m-S, S-[B / S]m-X-[S / B]m-S, S-[I / S]m, S-[I / S]m-S, S-[I / S]m-X-[S / I]m-S, S-[B / I / S]m, S-[B / I / S]m-S, S-[B / I / S]m-X-[S / I / B]m-S, (S-[B / S]m)n-X, (S-[I / S]m)n-X, (S-[B / I / S]m)n-X (where m is an integer, X is the residue of either a coupling agent or a polyfunctional initiator, and n is an integer from 2 to about 30), which can be used alone or in a formulation to obtain counter-tapered thermoplastic elastomer compositions and their hydrogenated, selectively hydrogenated, and partially hydrogenated equivalents.

[0040] The novel counter-tapered thermoplastic elastomer composition may be a polymer blend obtained by in-situ partial coupling and / or partial initiation using a coupling agent and / or a polyfunctional initiator, or a polymer blend of a multi-arm, branched, or radial polymer obtained by complete coupling and / or complete initiation and a separately prepared diblock copolymer. The counter-tapered thermoplastic elastomer composition may be a blend prepared in-situ by adding a suitable amount of a coupling agent at the end of the polymerization of the counter-tapered diblock A-[A / B] copolymer of the present invention to form the desired (A-[A / B])n-X linear triblock and / or multi-arm coupling block copolymer. Partial coupling is achieved by controlling the theoretical mixing ratio of the coupling agent to the living polymer. Also, the counter-tapered thermoplastic elastomer composition may be a blend prepared in-situ by using a suitable polyfunctional initiator in combination with a typical monofunctional initiator such as alkyllithium to initiate the polymerization of the counter-tapered diblock [A / B]-A copolymer of the present invention and form the desired X-([A / B]-A)n linear triblock and / or multi-arm coupling block copolymer. Partial initiation is achieved by controlling the theoretical mixing ratio of the polyfunctional initiator to the monofunctional initiator. The novel counter-tapered thermoplastic elastomer composition used in the present invention may have from 2 to 30 anionic polymerization polymer chains (arms) per molecule of the initiator or coupling agent. These branched and radial linear triblock and multi-arm coupling block copolymers may have a peak molecular weight of from about 40,000 to about 750,000 g / mol. This preferably includes a counter-tapered thermoplastic elastomer composition having a weight average molecular weight of from about 30,000 to 500,000 g / mol.In some embodiments of the novel counter-tapered thermoplastic elastomer composition, the composition of the vinyl aromatic monomer is preferably in the range of from about 10 to about 85 weight percent, more preferably from about 10 to about 70 weight percent, and even more preferably from about 10 to 55 weight percent. The vinyl content of the novel counter-tapered thermoplastic elastomer composition may be preferably in the range of from about 15 to about 90 weight percent, more preferably from about 15 to about 85 weight percent, and even more preferably from about 15 to 80 weight percent, based on the total amount of the conjugated diene monomer in the counter-tapered copolymer block [A / B]. The present invention is not limited to counter-tapered thermoplastic elastomer compositions that fall within the preferred molecular weight, composition, and vinyl configuration ranges.

[0041] Anionic polymers can be produced by any suitable method known in the art, such as those described in U.S. Patent Nos. 3,281,383 and 3,753,936, which are hereby incorporated by reference in their entirety. In such methods, anionic polymers are produced by contacting an anionically polymerizable monomer with an organolithium compound as an initiator. Preferred classes of such compounds can be represented by the formula RLi, where R is a hydrocarbon radical selected from the group consisting of aliphatic, cycloaliphatic, and aromatic radicals containing 1 to 20 carbon atoms, although higher molecular weight initiators can be used. Many anionic polymerization initiators are well known and commercially available. Monofunctional organolithium compounds such as butyllithium are examples of commonly used initiators. Specific examples of such initiators include: cycloalkyl lithium compounds such as methyllithium, ethyllithium, tert-butyllithium, sec-butyllithium, n-butyllithium, n-decyllithium, isopropyllithium, eicosyllithium, cyclohexyllithium, and aryllithium compounds such as phenyllithium, naphthyllithium, p-tolyllithium, 1,1-diphenylhexyl lithium, etc. Monofunctional organolithium compounds substituted with protected polar functional groups can also be used as initiators for anionic polymerization.

[0042] The amount of initiator varies depending on the desired molecular weight of the anionic polymer. By adding about 0.28 to 5.0 millimoles of RLi initiator per mole of monomer corrected by a factor of 100 / (MW of the monomer), a number average molecular weight of about 20,000 to 350,000 can be obtained.

[0043] Also, a multi-functional organic lithium initiator can be used as an initiator to prepare branched and radial linear triblock or multi-arm block copolymers having a desired functionality range of 2 to about 30 anionic polymerization polymer chains (arms) per initiator molecule. The multi-functional organic lithium initiator is easily prepared by the direct addition reaction of a stoichiometric amount of a mono-functional organic lithium compound to polyvinyl compounds such as 1,3-diisopropenylbenzene, 1,3,5-triisopropenylbenzene, 1,3-bis(1-phenylethenyl)benzene, 1,3,5-tris(1-phenylethenyl)benzene, 1,3-divinylbenzene, and 1,3,5-trivinylbenzene. An oligomeric polyvinyl compound can be used to prepare a multi-functional organic lithium initiator having high functionality. Mono-functional organic lithium compounds such as butyllithium are examples of initiators commonly used in the above addition reaction. Specific examples of such commonly used initiators include tert-butyllithium, sec-butyllithium, and n-butyllithium. Also, a multi-functional organic lithium initiator may be prepared using a mono-functional organic lithium compound substituted with a protected polar functional group. The multi-functional organic lithium compounds may partially initiate anionic polymerization by the multi-functional organic lithium compounds, either with each other and / or in combination with mono-functional organic lithium compounds. The partial initiation is achieved by controlling the theoretical mixing ratio of the multi-functional initiator to the mono-functional initiator.

[0044] Anionic polymerization is typically carried out in an inert hydrocarbon solvent at a relatively low temperature under vacuum or in an inert atmosphere using highly purified reagents to prevent premature termination of the polymerization reaction. The anionic polymerization reaction can be carried out in various organic solvents. Examples of suitable solvents include, but are not limited to, the following: pentane, hexane, heptane, octane, cyclopentane, cyclohexane, cycloheptane, benzene, naphthalene, toluene, xylene, methyl ether, methyl ethyl ether, diethyl ether, tetrahydrofuran, acetone, methyl ethyl ketone, and mixtures thereof. In particular, cyclohexane is well-suited for use as a solvent for anionic polymerization.

[0045] Anionic polymerization is usually carried out at a temperature in the range of -100°C to 150°C, preferably -75°C to 75°C. Usually, 50 to 90% by weight, preferably 70 to 85% of the reaction solvent is used to control the viscosity inside the reaction zone. The typical residence time for anionic polymerization varies from 0.1 to 5 hours, preferably from 0.2 to 2 hours, depending on the reaction temperature and initiator level.

[0046] Polar additives that are known in the art and can be used to prepare the counter-tapered thermoplastic elastomer composition of the present invention are Lewis bases such as ethers and tertiary amines, Group Ia alkali metal alkoxides, and combinations thereof. Specific examples of these suitable ether polar additives include monofunctional, polyfunctional, and oligomeric alkyl and cyclic ethers such as dimethyl ether, diethyl ether, ethyl methyl ether, ethyl propyl ether, di-n-propyl ether, tetramethylene oxide (tetrahydrofuran), 1,2-dimethoxyethane, bis-tetrahydrofuran, ditetrahydrofuranyl propane (DTHFP), and combinations thereof. Specific examples of these suitable tertiary amine polar additives include monofunctional, polyfunctional, and oligomeric alkyl and cyclic tertiary amines such as dimethylethylamine, trimethylamine, triethylamine, N,N,N’,N’-tetramethylethylenediamine (TMEDA), N,N,N’,N’,N’’-pentamethyldiethyltriamine, and combinations thereof. Specific examples of these suitable Group Ia alkali metal alkoxides (lithium, sodium, potassium, rubidium, and cesium salts) include monofunctional, polyfunctional, and oligomeric alkyl and cyclic metal alkoxides such as sodium tert-butoxide, sodium tert-amylate, sodium mentholate, potassium tert-butoxide, potassium tert-amylate, potassium mentholate, and combinations thereof.

[0047] The amount of suitable polar additives ranges from 0.0005 to 50 weight percent of the total reaction mixture, preferably from 0.0005 to 10.0 weight percent of the total reaction mixture. A more preferred range is from about 0.0005 to about 5.0 weight percent of the total reaction mixture. The most preferred Lewis bases are TMEDA, THF, and DTHFP. A more preferred combination is a combination of two Lewis bases (i.e., one ether and one tertiary amine). A preferred combination is a combination of two alkali metal alkoxides (e.g., lithium and sodium, lithium and potassium). The preferred concentration of the polar additive or combination of polar additives depends on the type of one or more polar additives, as well as the desired monomer sequence length distribution, microstructure, and properties of the counter-tapered copolymer block [A / B]. The desired properties will then depend on the intended application of the counter-tapered thermoplastic elastomer composition.

[0048] Suitable conjugated dienes used in the construction of the counter-tapered thermoplastic elastomer composition of the present invention include, but are not limited to, the following: 1,3-butadiene, isoprene, 1,3-pentadiene, methylpentadiene, phenylbutadiene, 2,3-dimethyl-1,3-butadiene, 2,4-hexadiene, 1,3-hexadiene, 1,3-cyclohexadiene, 3,4-dimethyl-1,3-hexadiene, 1,3-octadiene, 4,5-diethyl-1,3-octadiene, and combinations thereof.

[0049] Preferred conjugated dienes for use in the production of the counter-tapered thermoplastic elastomer composition of the present invention include, but are not limited to, 1,3-butadiene, isoprene or 2-methyl-1,3-butadiene, 2-ethyl-1,3-butadiene, piperylene or 1,3-pentadiene, methylpentadiene, phenylbutadiene, 2,3-dimethyl-1,3-butadiene, 2,4-hexadiene, 1,3-hexadiene, 1,3-cyclohexadiene, 3,4-dimethyl-1,3-hexadiene, 1,3-octadiene, 4,5-diethyl-1,3-octadiene, β-myrcene or 7-methyl-3-methylene-1,6-octadiene, β-farnesene or 7,11-dimethyl-3-methylene-1,6,10-dodecatriene, mixtures of their isomers and combinations thereof. These preferred conjugated diene monomers for the counter-tapered thermoplastic elastomer composition of the present invention include, but are not limited to, biosource and / or biobased conjugated diene monomers, substituents for modifying compatibility and / or reactivity, and at least one substituent selected from C1-C18 vinyl, alkyl or alkoxy, cycloalkyl and / or aromatic groups, substituted conjugated diene monomers having at least one substituent, protected functionalized conjugated diene monomers, mixtures of their isomers, and combinations thereof. The most preferred substituted conjugated diene monomer having at least one substituent for modifying compatibility and / or reactivity with a C1-C18 vinyl group is one in which the substituent has at least one terminal and / or non-terminal vinyl group and increases the vinyl constitutional unit without causing side reactions of the substituent during polymerization.

[0050] Suitable monovinyl aromatic monomers used in the construction of the novel counter-tapered thermoplastic elastomer composition of the present invention include, but are not limited to, 3-methylstyrene, α-methylstyrene, p-methylstyrene, α,4-dimethylstyrene, t-butylstyrene, o-chlorostyrene, 2-butenylnaphthalene, 4-t-butoxystyrene, 3-isopropenylbiphenyl, 4-vinylpyridine, 2-vinylpyridine, and styrene and styrene derivatives such as isopropenylnaphthalene, 4-n-propylstyrene, and combinations thereof.

[0051] Preferred vinyl aromatic monomers used in the production of the novel counter-tapered thermoplastic elastomer composition of the present invention include, but are not limited to, styrene and styrene derivatives such as 3-methylstyrene, p-methylstyrene or 4-methylstyrene, vinyltoluene, α-methylstyrene or alpha-methylstyrene, α,4-dimethylstyrene, t-butylstyrene, o-chlorostyrene, 2-butenylnaphthalene, 4-t-butoxystyrene, 3-isopropenylbiphenyl, 4-vinylpyridine, 2-vinylpyridine and isopropenylnaphthalene, 4-n-propylstyrene, mixtures of their isomers and combinations thereof. These vinyl aromatic monomers preferred for the counter-tapered thermoplastic elastomer composition of the present invention include, but are not limited to, biosource and / or biobased unsubstituted and substituted vinyl aromatic monomers, protected functionalized unsubstituted and substituted vinyl aromatic monomers (including, but not limited to, hydrosilylation monomers and hydrosilane-functional monomers), mixtures of their isomers, and combinations thereof. Substituted vinyl aromatic monomers having at least one substituent selected from C1-C18 vinyl, alkyl or alkoxy, cycloalkyl and / or aromatic groups include various compounds including, but not limited to, vinyl-substituted styrene, alkyl-substituted styrene, alkoxy-substituted styrene, vinylnaphthalene, alkyl-substituted vinylnaphthalene, 1,1-diphenylethylene, 1,4-diisopropenylbenzene, 1,4-bis(1-phenylethenyl)benzene, mixtures of their isomers, and combinations thereof. The most preferred substituted vinyl aromatic monomers having at least one substituent for modifying the compatibility and / or reactivity with C1-C18 vinyl groups are those in which the substituent has at least one terminal and / or non-terminal vinyl group and increases the vinyl structural unit without causing side reactions of the substituent during polymerization.

[0052] In some embodiments of the methods provided herein, a novel counter-tapered thermoplastic elastomer composition undergoes complete or partial coupling to prepare branched and radial linear triblock or multi-arm block copolymers. Partial coupling means that some of the living anionic polymer chain ends undergo coupling with a coupling agent. The coupling agent preferably couples 2 to 30 anionic polymer chains (arms), although coupling agents capable of coupling a larger number of chains can also be used. Suitable coupling agents for use in the complete or partial coupling step include, but are not limited to, the following: tin halides, silicon halides, functionalized tin compounds, functionalized silicon compounds such as silane compounds, and functionalized oligomer compounds such as those listed in U.S. Patent No. 7,517,934. The entire disclosure of U.S. Patent No. 7,517,934 is incorporated herein by reference. Silicon tetrachloride, methyltrichlorosilane, dimethyldichlorosilane, and tin tetrachloride are specific examples of suitable coupling agents, and silicon tetrachloride and dimethyldichlorosilane are particularly well-suited for this application. Partial coupling is achieved by controlling the theoretical mixing ratio of the coupling agent to the living polymer. Partial coupling can provide a polymer formulation having desired properties.

[0053] Preferred coupling agents for use in whole or partial coupling processes include, but are not limited to, tin halides, silicon halides, tin alkoxides, silicon alkoxides, alkyl-substituted tin and silicon trihalides, alkyl-substituted tin and silicon dihalides, hexahalodisilanes, hexahalodisiloxanes, functionalized tin compounds, functionalized silicon compounds, alkoxysilane compounds, alkoxy-substituted silicon and tin halides, alkoxyalkylsilanes, epoxy silane compounds, amino and / or amine silane compounds, isocyanate silane compounds, methacrylate silane compounds, acrylate silane compounds; sulfur silane compounds, fluorosilane compounds, fluoroalkylsilane compounds, sulfanyl silane compounds, mercapto silane compounds, sulfurized silane compounds, sulfurized tin compounds, and functionalized oligomer compounds, polyfunctional compounds, mixtures or combinations of the aforementioned compounds such as those described in U.S. Pat. Nos. 3,281,383, 7,517,934 and 8,883,927. The entire disclosures of U.S. Pat. Nos. 3,281,383, 7,517,934 and 8,883,927 are incorporated herein by reference. Other suitable coupling agents include siloxanes, polyfunctional epoxides, esters such as methyl benzoate compounds, epoxidized oils, and polyalkenyl compounds. For example, polyalkenyl coupling agents disclosed in U.S. Pat. Nos. 3,985,830; 4,391,949; and 4,444,953; and Canadian Patent No. 716,645. Suitable polyalkenyl coupling agents include divinylbenzene, preferably m-divinylbenzene. Functionalized silicon and tin compounds can be used to attach specific functional groups to the polymer chains of novel modified diene copolymers, including but not limited to chloropropyltrialkoxysilane, trialkyltin chloride and trialkoxytin chloride, such as chloropropyltriethoxysilane, chloropropyltrimethoxysilane, trimethyltin chloride, trimethoxytin chloride, triethyltin chloride, triethoxytin chloride, trioctyltin chloride, trioctyloxytin chloride, etc.A coupling agent, a combination of coupling agents, or a mixture of coupling agents is added sequentially, partially, intermittently, or continuously during polymerization to achieve polydispersity, functionality, asymmetry, etc. Preferred combinations are those combining two silicon coupling agents such as silicon halide and silicon alkoxide. More preferred combinations are those combining a silicon compound and a tin compound such as silicon halide and tin alkoxide. The most preferred combination is that of a silicon compound and a functionalized oligomer compound. The most preferred combination is that of a silicon compound, a tin compound, and a functionalized oligomer compound.

[0054] In additional embodiments, the novel counter-tapered thermoplastic elastomer composition undergoes overall or partial linking to join polymer chains, retains living characteristics, and polymerizes remaining or new monomers to prepare miktoarm, hybrid, and / or asymmetric novel counter-tapered thermoplastic elastomer compositions containing at least one polymer chain (intramolecular) having at least one different characteristic such as composition, microstructure, size, vinyl configuration, etc., by preparing linear, branched, or radial, multi-arm or graft-structured copolymers. Partial linking means that a portion of the entire anionically polymerized living polymer chain ends undergoes linking by a linking agent. The linking agent desirably links 2 to 30 anionically polymerized polymer chains (number of arms), although linking agents capable of linking more chains can also be used. Suitable linking agents for use in the overall or partial linking step include, but are not limited to, polyvinyl compounds such as 1,3-diisopropenylbenzene, 1,4-diisopropenylbenzene, 1,3,5-triisopropenylbenzene, 1,3-bis(1-phenylethenyl)benzene, 1,4-bis(1-phenylethenyl)benzene, 1,3,5-tris(1-phenylethenyl)benzene, 1,3-divinylbenzene, 1,4-divinylbenzene, 1,3,5-trivinylbenzene, and polyvinyl compounds substituted with at least one substituent such as alkyl, alkoxy, cycloalkyl, cycloalkoxy, etc. Oligomeric polyvinyl compounds can be used as highly functional linking agents.

[0055] When organometallic compounds of different metals derived from Group IIa, Group IIb, and Group IIIa, including magnesium, zinc, and aluminum, are mixed with an alkyllithium initiator, they can be used as a polymerization rate regulator. Specific examples of suitable polymerization rate regulators are dibutylmagnesium, diethylzinc, triethylaluminum, and combinations thereof. The polymerization rate regulator can be used to control the temperature profile of the polymerization. The polymerization rate regulator contributes to the control of the polymerization step either in isothermal mode or in pseudo-adiabatic mode up to the peak temperature over a pre-established residence time.

[0056] In some embodiments of the methods provided herein, the novel counter-tapered thermoplastic elastomer compositions are polymerized in a batch process, a programmed batch process, and / or a semi-batch process. As will be recognized by those skilled in the art, the described synthesis of the counter-tapered thermoplastic elastomer compositions can occur in a reaction setting that includes a process carried out at the temperatures, solvent ratios, and flow rates necessary to reach the described residence times and stoichiometric conditions.

[0057] Applications Another aspect of the present invention provides compositions and articles made from a novel counter-tapered thermoplastic elastomer composition, reinforcing materials made from a mixture of the novel counter-tapered thermoplastic elastomer composition and a material to be reinforced, and articles made from such reinforcing materials. Another aspect of the present invention provides a novel counter-tapered thermoplastic elastomer composition, formulations with other block copolymers having enhanced adhesion to a specific base, and articles made from materials with enhanced adhesion. The novel counter-tapered thermoplastic elastomer composition achieves a better balance of processability and reinforcing performance for application to various asphalts, adhesives, and sealants. The novel counter-tapered thermoplastic elastomer composition provides for the above-mentioned applications processability advantages such as short dispersion time, low mixing temperature, low viscosity, excellent storage stability, etc., and better reinforcing advantages such as high elastic response, wide range of performance grades, high adhesion, higher filler loading capacity, and better compromise between high-temperature and low-temperature properties. These processability and reinforcing advantages enable the novel counter-tapered thermoplastic elastomer composition to preferably meet the requirements of a wide range of applications such as road paving, roofing materials, roof boards, waterproof membranes, adhesive tapes and labels, contact and spray adhesives, and sealants.

[0058] Among the desired commercial applications, some of the novel counter-tapered thermoplastic elastomer compositions provided herein are well-suited for use as adhesives and sealants, including pressure-sensitive adhesives, non-pressure-sensitive adhesives, hot melt adhesives, hot melt and solvent-based mastics, and sealant agents. Further, the counter-tapered thermoplastic elastomer compositions may be designed for use as compatibilizers or reinforcing agents in asphalt and polymer formulations. Asphalts that can benefit from the compatibilizers or reinforcing agents provided herein include those commonly used in road paving, roofing materials, and sealant applications. Applications to paving include the strengthening of asphalt cement / binders used to make asphalt concrete for road construction, as well as the modification of materials for road repair, patching, and maintenance, including chip sealing, resealing, repaving, and recycling. Applications to roofing materials include the strengthening of roof boards and the modification of materials for roof waterproofing, repair, and maintenance. Also, certain types of counter-tapered thermoplastic elastomer compositions can be used as reinforcing agents, viscosity modifiers, flow modifiers, processing aids, and impact modifiers for rubbers and plastics. The types of plastics that can benefit from the counter-tapered thermoplastic elastomer compositions are non-polar plastics. Non-polar plastics include, but are not limited to, polyolefins, polystyrene, and their copolymers.

[0059] As will be recognized by those skilled in the art, the optimal features and properties of the counter-tapered thermoplastic elastomer compositions will depend on the intended application. Some exemplary applications of the counter-tapered thermoplastic elastomer compositions are provided below. These applications are provided for illustrative purposes only and are not intended to limit the scope of the invention.

[0060] Reinforcement of Asphalt The modification of asphalt by high molecular weight elastomers is typically used to prepare modified asphalt binders that have improved performance compared to unmodified asphalt binders. The performance characteristics of asphalt products that are improved by adding polymers are: a) flexibility at low temperatures; b) resistance to flow and deformation at high temperatures; c) temperature sensitivity; d) tensile strength; e) modulus of rigidity at high temperatures; f) asphalt-aggregate adhesion; g) resistance to surface wear. Asphalt products that benefit from polymer modification are paving binders, seal coats, trunk road joint sealants, waterproof membranes, coating agents, pipeline mastics, and pipeline wrapping tapes, etc.

[0061] Since high molecular weight polymers tend to be immiscible with asphalt, the modification of asphalt by elastomers based on monovinyl aromatic and conjugated diene monomers is difficult because of limited phase stability. The limited phase stability results in asphalt-polymer separation that has a negative impact on the performance characteristics of asphalt products. Phase stability has typically been improved either by crosslinking the asphalt-polymer blend or by increasing the compatibility between the polymer and asphalt. Also, high molecular weight polymers have an adverse effect on the processing characteristics of modified asphalt binders by significantly increasing the melt viscosity of the asphalt-polymer blend. Modifications of prior art polymer compositions and / or structures have been used to improve processing characteristics and reduce the cost of asphalt-polymer blends, but often the modification of performance characteristics is not desirable.

[0062] By adding the counter-tapered thermoplastic elastomer composition provided herein to asphalt, the inventors have found that the processing characteristics are maximized without compromising the performance characteristics of the modified asphalt compared to modified asphalt formulated with prior art copolymers. The counter-tapered thermoplastic elastomer composition of the present invention provides an asphalt blend having lower melt viscosity and higher fluidity; increased dispersibility and compatibility; higher compounding stability; and good elastic and thermoplastic properties. The inventors have also found that the counter-tapered thermoplastic elastomer composition of the present invention can be used as a compatibilizer or reinforcing agent. Asphalts that can benefit from the compatibilizers or reinforcing agents provided herein include those commonly used for applications to road pavements, roofing materials, and sealants. Applications to pavements include the strengthening of asphalt cement / binders used to produce asphalt concrete for road construction, and the modification of materials for road repair, rehabilitation, and maintenance, including chip sealing, resealing, repaving, and recycling. Applications to roofing materials include the strengthening of roof boards and the modification of materials for roof waterproofing, repair, and maintenance.

[0063] The inventors have also found that emulsions of asphalt previously modified with the counter-tapered thermoplastic elastomer composition of the present invention improve asphalt adhesion to aggregate particles when used for road repair, rehabilitation, and maintenance. The inventors have also found that the compatibilizers or reinforcing agents provided herein can be encapsulated or incorporated into commercially available block copolymers to improve the phase stability and processing characteristics of modified asphalt blends.

[0064] In countries such as the United States of America, modified asphalt is evaluated according to the standards of the American Association of State Highway and Transportation Officials (AASHTO), which grades asphalt according to performance grade (PG). The standards of the American Society for Testing and Materials (ASTM) are also used for asphalt evaluation. Among the modified asphalt properties evaluated are the following.

[0065] a) Ring and Ball Softening Point (RBSP). This can be measured in accordance with ASTM D 36 and indicates the temperature at which the asphalt softens and becomes unsuitable for the intended application. The softening point or temperature is obtained using a ring and ball apparatus, also known as an R&B apparatus.

[0066] b) Penetration at 25°C. This is a parameter related to the stiffness of the modified asphalt. Penetration is measured as the distance that a loaded needle or cone sinks into the asphalt over a set period, in accordance with ASTM D5.

[0067] c) Brookfield Viscosity. This is a property related to the steady flow stability of the asphalt. Brookfield Viscosity can be measured in accordance with ASTM D4402. d) Resilience is a property that serves as a measure of the elasticity of the asphalt material. Resilience can be measured in accordance with ASTM D 113.

[0068] e) Rutting factor: G / sinδ at various temperatures (where G is the complex modulus and δ is the phase angle) is useful for determining the performance of modified asphalt at high temperatures. This factor indicates how resistant the asphalt is to permanent deformation that may occur over time due to repeated loading at high temperatures or when the pavement is exposed to a load that is much larger than the maximum value allowed in the original design. Thus, a higher rutting factor value at high temperatures indicates that the asphalt can withstand greater deformation than a material with a lower rutting factor value at the same test temperature. The rutting factor can be measured in accordance with AASHTO TP5. * / sinδ (where G * is the complex modulus and δ is the phase angle) is useful for determining the performance of modified asphalt at high temperatures. This factor indicates how resistant the asphalt is to permanent deformation that may occur over time due to repeated loading at high temperatures or when the pavement is exposed to a load that is much larger than the maximum value allowed in the original design. Thus, a higher rutting factor value at high temperatures indicates that the asphalt can withstand greater deformation than a material with a lower rutting factor value at the same test temperature. The rutting factor can be measured in accordance with AASHTO TP5.

[0069] f) Upper Limit Temperature. By determining the rutting factor, it is possible to determine the upper limit temperature in accordance with AASHTO standards. The upper limit temperature relates to the highest temperature at which the asphalt can maintain an appropriate stiffness to resist rutting.

[0070] g) Lower limit temperature. By determining the rutting coefficient, it is possible to determine the lower limit temperature in accordance with the AASHTO standard. The lower limit temperature relates to the lowest temperature at which asphalt can maintain appropriate flexibility to resist thermal cracking.

[0071] h) Phase separation is an important factor when modifying asphalt with elastomers due to the problems described above. The phase separation index is measured as the percentage difference between the TRBSP measured at the top and bottom surfaces of a cylindrical probe fabricated inside a sealed tube containing the formulated asphalt, placed vertically without stirring, aged at 163 °C for 48 hours, and solidified at 30 °C. The percentage difference in TRBSP provides a measure of the compatibility between the asphalt-rich phase and the polymer-rich phase in the asphalt / polymer blend.

[0072] Two specific applications where the reinforced asphalt can be used are applications to road paving and to roofing materials / waterproof coating agents. In some cases where the reinforced asphalt is used for road paving applications, 0.5 to 8 parts, preferably 2 to 5 parts, of the counter-tapered thermoplastic elastomer composition of the present invention can be mixed with 99.5 to 92 parts, preferably 98 to 95 parts, of asphalt to improve its performance characteristics. In some cases where the reinforced asphalt is used for applications to roofing materials or waterproof coating agents, 3 to 25 parts, preferably 6 to 16 parts, of the counter-tapered thermoplastic elastomer composition of the present invention can be mixed with 97 to 75 parts, preferably 94 to 84 parts, of asphalt to improve its performance characteristics. Suitable asphalts for use with the counter-tapered thermoplastic elastomer composition of the present invention include, but are not limited to, the following: PG64-22 asphalt, or other asphalts widely used for applications to road paving and roofing materials such as natural rock asphalt, lake asphalt, petroleum asphalt, air-blown asphalt, cracked asphalt, and residual asphalt.

[0073] In certain embodiments of the present invention, the very low viscosity of the asphalt formulation prepared using the counter-tapered thermoplastic elastomer composition provided herein contributes to improved dispersion into the asphalt, and also facilitates the processing, handling, and application of the modified asphalt blend by improving the pumping capacity and / or reducing the energy required to do so. This also means significant cost savings and a more environmentally friendly process. The high softening point temperature of the asphalt modified with the counter-tapered thermoplastic elastomer composition of the present invention should provide better resistance to flow and deformation at high temperatures. Surprisingly, asphalt modified with the counter-tapered thermoplastic elastomer composition of the present invention and formulated with a low polymer content provides similar performance characteristics (TRBSP) and lower viscosity compared to asphalt modified with prior art commercial polymers. This also means significant cost savings and an energy-efficient process.

[0074] In another embodiment of the present invention, an asphalt and / or bitumen composition formulated with a fully coupled counter-tapered thermoplastic elastomer composition having a linear structure (A-[A / B])-X-([B / A]-A) and / or a coupled radial and / or multi-arm structure (A-[A / B])n-X provides improved performance characteristics such as a high softening point temperature (TRBSP), which means much better resistance to flow and deformation at high temperatures. The asphalt and / or bitumen composition modified with the fully coupled counter-tapered thermoplastic elastomer composition of the present invention can be formulated with a low polymer content and can provide similar performance characteristics (i.e., TRBSP) and lower viscosity as compared to asphalt and / or bitumen compositions modified with conventional commercial polymers. This may also mean significant cost savings and an energy-efficient process.

[0075] In certain embodiments of the present invention, the counter-tapered thermoplastic elastomer composition provided herein imparts one or more of the following properties to an asphalt composition: a) a maximum application temperature of about 50 to 100 °C, measured as the temperature at which the rutting factor or dynamic shear stiffness (G * / sinδ) takes a value of 1.0 KPa (measured in accordance with AASHTO TP5); b) a TRBSP of about 40 to 110 °C (measured in accordance with ASTM D36); c) an asphalt penetration at 25 °C of about 30 to 75 dmm for applications to road pavements and about 50 to 100 for applications to roofing materials and waterproof coating agents (in accordance with ASTM D5); and d) a kinematic viscosity at 135 °C of about 500 to 3000 cP and preferably 1000 to 2000 cP for applications to road pavements, or a kinematic viscosity at 190 °C of about 1000 to 6000 cP and preferably 1500 to 4000 cP (in accordance with ASTM D4402) for applications to roofing materials and waterproof coating agents.

[0076] Adhesives, sealants, and coating agents High molecular weight elastomers are typically formulated into compositions useful as adhesives, sealants, and coating agents so as to provide the appropriate balance between adhesion, and adhesion and cohesion properties for each application. Elastomers based on monovinyl aromatic and conjugated diene monomers are widely used as pressure-sensitive adhesives, spray and contact adhesives, panel and architectural mastics, sealants, and coating agents. Isoprene-containing elastomers are preferred for hot melt pressure-sensitive adhesives because they can be readily tackified at low cost. Butadiene-containing elastomers are generally preferred for construction or laminating adhesives because they can provide rigidity and adhesion. The hydrogenated forms of these elastomers are preferred for sealants because they have higher weather resistance. The performance characteristics necessary to successfully formulate adhesive, sealant, and coating agent products with elastomers are as follows: a) tackifier resin compatibility with the elastomer; b) continuous elastomeric phase morphology for adhesion and shear resistance; c) flexible and low modulus elastomers for tack development and energy dissipation; d) suitable tackifier resins that raise the glass transition temperature (Tg) of the elastomeric phase of the elastomer to increase the dissipation of strain energy.

[0077] Conventional high molecular weight polymers have an adverse effect on the processing characteristics of adhesive, sealant, and coating formulations by significantly increasing the melt and solution viscosities of such formulations. Modification of conventional polymer compositions and / or structures has been used to improve processing characteristics and reduce the cost of formulations for use in adhesives, sealants, and coatings, but often the modification of performance characteristics is undesirable. Among the desired commercial applications, some of the novel counter-tapered thermoplastic elastomer compositions provided herein are well-suited for use as adhesives, sealants, and coatings, including pressure-sensitive adhesives, non-pressure-sensitive adhesives, hot melt adhesives, hot melt and solvent-based mastics, sealants, and coatings. The development of low melt viscosity and low solution viscosity is particularly important for pressure-sensitive adhesives, hot melt adhesives, and solvent-based adhesives. The inventors have discovered that the addition of the novel counter-tapered thermoplastic elastomer compositions provides excellent processing characteristics to the formulations without significantly affecting the desired performance characteristics of adhesive, sealant, and coating products. Notably, hot melt pressure-sensitive adhesives prepared with these novel counter-tapered thermoplastics exhibit higher compatibility with various resins, excellent adhesion, and very high shear resistance. It has also been discovered that compatibilizers or reinforcing agents provided herein can be encapsulated and incorporated into commercially available block copolymers to improve the phase stability and processing characteristics of adhesive formulations.

[0078] In some such applications, about 10 to 40, desirably 15 to 30, more desirably 18 to 25 parts by weight of the novel counter-tapered thermoplastic elastomer composition, or a mixture thereof with a commercially available block copolymer, is mixed with other conventional adhesive formulation components / additives such as tackifying resins, plasticizers, coupling agents, crosslinking agents, photoinitiators, fillers, processing aids, stabilizers, and antioxidants, etc., to impart improved properties to such a composition as compared to an adhesive formulated with a prior art elastomer as a suitable control. Examples of suitable tackifying agents include resins having high and low softening points that are compatible with the polymer. Such resins include hydrogenated resins, rosin esters, polyterpene resins, terpene phenol resins, indene-cumarone resins, and aliphatic hydrocarbon resins. In some exemplary embodiments, the amount of tackifying resin in the composition ranges from about 40 to 65 weight percent. Plasticizers, generally known as extender oils, include mineral oils, paraffinic oils, and naphthenic oils. In some exemplary embodiments, the amount of plasticizer in the composition ranges from about 15 to 35 weight percent. Antioxidants may be used to inhibit thermal and UV oxidation processes and are typically added to the adhesive composition in an amount of about 0.05 to 3 weight percent. Examples of antioxidants include phenolic compounds, phosphite esters, amines, and thio compounds. Some examples of commercially available adhesive components / additives are listed in Table A below.

[0079] In another embodiment of the present invention, an adhesive composition formulated using a fully coupled counter-tapered thermoplastic elastomer composition having a linear structure (A-[A / B])-X-([B / A]-A) and / or a coupled radial and / or multi-arm structure (A-[A / B])n-X can provide improved performance characteristics such as a high softening point temperature (TRBSP) and a high shear adhesion failure temperature (SAFT), which means high heat resistance and much better resistance to flow and deformation at high temperatures. The adhesive composition comprising the fully coupled counter-tapered thermoplastic elastomer composition of the present invention can be formulated with a lower polymer content and can provide performance characteristics (i.e., TRBSP) similar to those of an adhesive composition formulated with a conventional commercially available polymer and a lower viscosity. This can also mean significant cost reduction and energy-saving processes.

[0080]

Table 1-1

[0081]

Table 1-2

[0082] The Sylvalite, Sylvares®, and Wingtack® products in Table A are available from Arizona Chemical. The Foral®, Pentalyn®, Permalyn, Piccotac®, and Eastotac® products are available from Eastman / Hercules. The Shellflex products are available from Shell. Primol 352 is available from Esso or ExxonMobil. The RPO and P.Oil products are available from IPISA or Ingenieria y Procesos Industriales, S.A. The Irganox® products are available from Ciba Specialty Chemicals, Inc. The Anox, Alkanox, and Lowinox® products are available from Great Lakes Chemical Corporation. The Ultranox and Weston products are available from GE Specialty Chemicals.

[0083] The novel counter-tapered thermoplastic elastomer composition provides adhesive, sealant, and coating applications having reaction sites and crosslinkable moieties that allow for crosslinking by photocuring, thermosetting, and chemical curing. The reaction sites can directly effect crosslinking of the novel counter-tapered thermoplastic elastomer composition and / or be adapted for further functionalization to promote crosslinking under more suitable mild conditions during application. The novel reactive adhesive, sealant, and coating compositions comprising the counter-tapered thermoplastic elastomer composition of the present invention can be manufactured and cured by any suitable method known in the art, such as those described in U.S. Patent Nos. 8,703,860, 7,799,884, 7,432,037, 6,926,959, 5,804,663, and 4,306,049, and European Patent No. 0097307, which are hereby incorporated by reference in their entirety. Reinforcing materials comprising either the counter-tapered thermoplastic elastomer composition, or a polymer blend and mixture comprising the counter-tapered thermoplastic elastomer, achieve an improved balance of compatibility and reactivity tailored to various applications such as adhesives, sealants, coatings, etc., and processability and reinforcement performance. The novel counter-tapered thermoplastic elastomer composition, and its polymer blends, and mixtures with other suitable polymers are useful for pressure and non-pressure sensitive, hot melt, and solvent-based formulations for end uses such as adhesives for taping, labeling, packaging, construction, and positioning, including solvent-based mastics and sealants. The novel counter-tapered thermoplastic elastomer composition is useful for spray adhesives and contact adhesives that have high heat resistance, low energy processability, and low volatile organic compound (VOC) emissions compared to solvent-based formulations, particularly low viscosity and reactive hot melt adhesive compositions.More specifically, the novel counter-tapered thermoplastic elastomer composition provides customized compatibility with compounding ingredients, reactive sites susceptible to modification, crosslinkable moieties enabling crosslinking that can be photocured, thermoset, and chemically cured, advantages of easy processing such as low mixing temperature and low application temperature, and excellent strengthening advantages such as high heat resistance, high cohesive strength and shear resistance, high tack and peel resistance for adhesive, sealant, and coating applications.

[0084] The novel adhesive composition comprising the counter-tapered thermoplastic elastomer of the present invention may be radiation curable, which is suitable for various end uses including, but not limited to, pressure-sensitive adhesives for high-performance tapes and labels such as freezer-grade tapes and labels, automotive adhesives, adhesive applications to wet surfaces such as medical applications. The novel adhesive composition of the present invention may further comprise at least one second polymer in combination with the counter-tapered thermoplastic elastomer composition. Examples of useful commercially available second block copolymers include, but are not limited to, Solprene®, Calprene® and Calprene® H block copolymers, Kraton® D and G series block copolymers, Europrene® Sol T block copolymers, Vector® block copolymers, and the like. The novel counter-tapered thermoplastic elastomer composition and the second block copolymer can further enhance radiation sensitivity and curability and further contribute to adhesive properties such as high heat resistance and high shear resistance by having more vinyl constitutional units in at least one conjugated diene homopolymer or copolymer block or segment. Preferred second block copolymers for the novel adhesive composition comprising the counter-tapered thermoplastic elastomer of the present invention include at least one styrene-isoprene-styrene (SIS) block copolymer having a styrene content of less than about 25 wt% in order to improve tack while maintaining high heat resistance such as high shear adhesion failure temperature (SAFT) and / or high ring-and-ball softening point temperature (TRBSP).

[0085] The novel adhesive, sealant, and coating compositions of the present invention, which can be radiation curable, counter-tapered thermoplastic elastomers, can be formulated with a suitable photoinitiator that generates crosslinking and / or polymerization initiating radicals when irradiated with a light source. Suitable photoinitiators include, but are not limited to, photoinitiators classified as cleavage-type photoinitiators and hydrogen abstraction-type photoinitiators depending on the pathway by which effective initiating radicals are generated. Hydrogen donors for hydrogen abstraction-type photoinitiators include amines, thiols, unsaturated rubbers such as polybutadiene and polyisoprene, and alcohols. In radiation curable compositions, crosslinking occurs upon exposure to ionizing radiation generated by the emission of ultraviolet light and / or highly accelerated nuclear particles such as electrons, neutrons, and alpha particles. The photoabsorbing chromophores used in the photoinitiator system are selected to match the emission band of the light source as closely as possible. The chromophores present in the photoinitiator render the photoinitiator sensitive to ultraviolet light and / or visible light, so that upon exposure to such a light source, it can initiate and / or participate in crosslinking. Suitable photoinitiators containing chromophore compounds that undergo hydrogen abstraction photochemical reactions include, but are not limited to, benzophenone and related aromatic ketones such as xanthone, thioxanthone, 4,4'-bis(N,N'-dimethylamino)benzophenone, benzyl, quinone, quinoline, anthraquinone, fluorene, acetophenone, xanthone, phenanthrene, and fluorenone. Suitable photoinitiators can typically be used in an amount of about 0.05 wt% to about 10 wt% of the formulated composition, preferably in an amount in the range of about 0.2 wt% to about 3 wt%, more preferably in the range of about 0.5 wt% to about 1.5 wt%. The specific amount of a suitable photoinitiator useful in the formulation varies depending on the polymer composition, radiation source, radiation dose received, production line speed, and the thickness of the adhesive, sealant, or coating composition on the substrate.

[0086] In an additional embodiment, the adhesive, sealant or coating composition of the present invention can be crosslinked by ultraviolet (UV) or electron beam (EB) irradiation by exposing it to ultraviolet radiation having a wavelength in the range of 180 - 400 nm, preferably 200 - 390 nm, in an air or nitrogen atmosphere for a time sufficient to achieve the desired amount of crosslinking. It is important that the emission wavelength of the UV light matches the absorption wavelength of the photoinitiator. The exposure time varies depending on the nature and intensity of the radiation, the specific UV photoinitiator and amount used, the polymer system, the film thickness, environmental factors, and the distance between the radiation source and the adhesive film. The irradiation can be carried out at any temperature, but most preferably at room temperature. In the case of a UV-curable composition, one or more photoactive initiators and / or photoactive coupling agents can be added to the adhesive, sealant, or coating composition of the present invention. To cure the adhesive, sealant or coating composition of the present invention, a radiation source having sufficient energy to generate free radicals when irradiated with the specific photoinitiator selected for use in the composition can be used. The preferred wavelength range for the photoinitiator is 400 - 250 nm. Suitable photocuring processes are disclosed in U.S. Pat. Nos. 4,181,752 and 4,329,384, which are incorporated herein by reference. Alpha-cleavage type photoinitiators are known in the art. Examples of commercially available products include, but are not limited to, Irgacure® 184 and Darocur® 1173. Preferred radical type photoinitiators include, but are not limited to, acylphosphine oxides, bisacrylphosphine oxides, combinations and mixtures thereof. Examples of useful commercially available products include, but are not limited to, Irgacure® 819, Irgacure® 1800, and Irgacure® 1850, as well as Lucirin TPO. In the case of curing by electron beam (EB) irradiation, a photoactive coupling agent may not be required to crosslink the adhesive, sealant, or coating composition containing the counter-tapered thermoplastic elastomer of the present invention.The composition of the present invention can also be cured by electron beam (EB) irradiation without using a photoinitiator. The dosage required to crosslink the composition can vary depending on the particular composition, but is usually in the range of about 1 to about 20 Mrad, preferably about 2 to about 10 Mrad. A process suitable for electron beam (EB) curing is described in U.S. Patent No. 4,533,566, which is incorporated herein by reference. The radiation energy density, and thus the line speed for sufficient curing, depends on the composition of the adhesive film being cured and, more importantly, its thickness.

[0087] The radiation curable hot melt adhesives, sealants, and coating compositions of the present invention include a novel counter-tapered thermoplastic elastomer composition and / or a second block copolymer having an increased vinyl constituent unit in at least one conjugated diene homopolymer or copolymer block or segment, thereby further increasing radiation sensitivity and curability, further contributing to enhanced performance characteristics such as high heat resistance and high shear resistance, and further including at least one of conventional components in typical formulations such as tackifying resins, extender oils and / or plasticizers, petroleum-derived waxes, antioxidants, photosensitizers (in the case of UV irradiation curing), and optionally resins compatible with vinyl aromatic blocks or segments, and can be cured by exposure to high energy ionizing radiation such as electron beam irradiation or by UV irradiation. The crosslinking reaction is preferably carried out at room temperature, but can also be carried out under an inert atmosphere at low or high temperature to prevent interference with the crosslinking of the block copolymer at the exposed surface, or by irradiating through a release paper or substrate to protect the exposed surface. Exposure to UV irradiation can be carried out by any known method. A suitable method is to expose a sample of either a layer obtained from a hot melt or a layer obtained by a solvent coating to UV irradiation by passing it under a UV light source at a constant speed. Preferred uses of the formulations of the present invention are the preparation of pressure sensitive adhesive tapes and the manufacture of labels. The backing sheet can be a plastic film, paper, or other suitable material, and the tape can include various other layers or coatings such as primers, release coatings, etc. used in the manufacture of pressure sensitive adhesive tapes.

[0088] In another aspect of the present invention, the novel counter-tapered thermoplastic elastomer composition may be useful in radiation-curable hot melt pressure-sensitive adhesives, radiation-curable sealant compositions, and radiation-curable coating compositions, as well as in manufactured articles comprising the cured adhesive, sealant composition, and / or coating composition. Suitable photoinitiators include, but are not limited to, those used in the preparation of pressure-sensitive hot melt adhesives, sealant compositions, and coating compositions, such as decorative and abrasion-resistant coatings, lacquers, fiber-reinforced composites, microelectronics encapsulated, die attach, optical fiber coatings, molding compounds, UV-curable structural resins, and the like. Suitable base resins for formulating the adhesive, sealant, and coating compositions of the present invention are well known to those skilled in the art. The adhesive, sealant, and coating compositions of the present invention may be formulated with liquid or solid olefinically unsaturated systems such as acrylates, methacrylates, maleimides, styrenics, maleic esters, fumaric esters, unsaturated polyester resins, alkyl resins, polyisoprene, polybutadiene, and thiol-ene compositions.

[0089] Another aspect of the present invention provides a novel hot melt adhesive, a sealant composition or a coating composition comprising the counter-tapered thermoplastic elastomer of the present invention, a reinforcing material composition, and an article manufactured from the reinforcing material composition. In one embodiment, the article comprises a novel hot melt adhesive, a sealant composition or a coating composition and a substrate. In another embodiment, the substrate includes a plastic film, an elastomeric fiber, a nonwoven material, a packaging material, or a structural material such as a shoe sole material, a furniture material, a bookbinding material. The articles of the present invention include, but are not limited to, disposable nonwovens such as feminine napkins, disposable stretchable articles such as diapers, reattachable / peelable tapes and labels, low temperature / freeze temperature tapes and labels, pressure sensitive adhesive articles such as automotive protective films. In another embodiment, the novel hot melt adhesive of the present invention is also useful, for example, as a construction adhesive for the manufacture of disposable products, is particularly suitable for use in elastic adhesive applications, and can be advantageously used in pressure sensitive end uses such as labels and tape applications at low temperature / freeze temperature. Thus, the novel hot melt adhesive of the present invention is particularly useful for the manufacture of stretchable nonwovens and for the manufacture of products such as baby diapers, training pants, adult incontinence briefs or underwear. Nonwovens are commercially used in disposable products such as diapers, adult incontinence products, sanitary napkins.

[0090] The present invention will be further described with reference to the following examples, which are presented for illustrative purposes only and are not intended to limit the scope of the present invention. Examples Example 1 Preparation of Counter-Tapered Thermoplastic Elastomer (CTTE) In Example 1, several novel counter-tapered thermoplastic elastomers (CTTE1 to 19) were prepared according to the method claimed in the present invention. Polymers CTTE1 to 14 and 17 are (A-[A / B])n-X block copolymers, and the A-[A / B] diblock before coupling consists of a monovinyl aromatic homopolymer block A block which is a polystyrene block (PS), and a counter-tapered copolymer block [A / B] which is a styrene / butadiene copolymer block. After coupling, an [A / B]-X-[B / A] intermediate block having a styrene unit-rich terminal region and a butadiene unit-rich central region was formed. CTTE15, 16, 18, and 19 were polymers prepared using only the counter-tapered copolymer block [A / B] of styrene / butadiene to exemplify the monomer distribution of the intermediate block copolymer chain before coupling.

[0091] A novel counter-tapered thermoplastic elastomer (CTTE) composition was characterized by GPC, 1H NMR, and DSC methods to determine the following: molecular weight average and molecular weight distribution characteristics such as the peak molecular weight (Mp), weight average molecular weight (Mw), and diblock to coupled ratio of linear diblock and coupling modes; microstructure characteristics such as total styrene, block styrene, and vinyl A / B block content; and the glass transition temperature (Tg) of the A / B counter-tapered copolymer block. In addition, the calculation of the intermediate block styrene and the blockiness of the intermediate block was carried out according to the methods used to characterize the polymer intermediate or "B" block, such as Calc.Mid PSC and Calc.Mid Blocky described in U.S. Patent Application Publication No. 2003 / 0176582A1, published on September 18, 2003, by KRATON Polymers U.S. LLC and Bening et al. Tables 1-2 show the results of the analytical characterization, and Table 3 shows the polymerization conditions of CTTE1-19. Described below are the basic procedures used to prepare these novel counter-tapered thermoplastic elastomers (CTTE) and to control the monomer distribution in the anionic copolymerization of 1,3-butadiene (B) and styrene (S) in the presence of ditetrahydrofuranylpropane (DTHFP) as a suitable polarity regulator and randomizing agent for the styrene / butadiene [S / B] counter-tapered copolymer block. The abbreviations used for the polymerization conditions in Table 3 below are defined as follows: CHx = cyclohexane; STY = styrene; and BD = 1,3-butadiene. For the novel counter-tapered thermoplastic elastomers CTTE1-14 and 17, silicon tetrachloride (SiCl4) was used as a coupling agent.

[0092] The novel counter-tapered thermoplastic elastomer (CTTE1-19) compositions of the present invention were prepared in a 5.3 liter reactor system operated in batch and / or semi-batch mode under an inert nitrogen atmosphere according to the teachings of the present invention. Immediately prior to addition to the reactor system, the solvent and monomer were thoroughly purified by flowing them through a set of columns filled with alumina and molecular sieves, reducing their moisture content to a maximum of 5 ppm. In the first polymerization step, an appropriate amount of purified solvent (CHx) was charged to the reactor and heated to an initial reaction temperature (Ti) of about 60 to about 65 °C. Once Ti was reached, a suitable polarity regulator (randomizing agent) such as ditetrahydrofuranylpropane (DTHFP) was added to the reactor, followed by the first addition (first STY) of monovinyl aromatic monomer of about 0 to about 17.5 wt% of the total monomer mixture. In the case of CTTE15, 16, 18, and 19, the first addition of styrene monomer was not performed in order to directly analyze by 1H NMR the isolated styrene / butadiene counter-tapered copolymer block, the intermediate block styrene, the block degree of the intermediate block, and the monomer distribution along the copolymer chain of the [A / B] counter-tapered copolymer block without performing the calculations necessary to remove interference with the monovinyl aromatic homopolymer block A (PS block) in CTTE1-14 and 17. This NMR analysis was possible by taking aliquots throughout the copolymerization and then performing NMR characterization. After stabilizing the reaction mixture at Ti, n-butyllithium or another suitable initiator in a suitable solvent solution was added directly to the reactor mixture containing an amount of polarity regulator necessary to efficiently initiate the anionic polymerization of at least the living polystyrene block. The amount of initiator was stoichiometrically calculated as described in the literature to form individual blocks having the desired molecular weight and to compensate for residual impurities. Thereafter, this first polymerization step was allowed to proceed adiabatically to complete conversion to form a monovinyl aromatic homopolymer block A having a peak molecular weight Mp of about 10,000 target value.

[0093] In the second polymerization step, the addition of both monomers was started simultaneously, and an addition amount of a second monovinyl aromatic monomer (second STY) of about 7.5 to about 9.1% by weight of the total monomer mixture was rapidly charged into the reactor at a specified charging rate over a predetermined charging time of about 1 minute, and an addition amount of a conjugated diene monomer (BD) of about 75.0 to about 90.9% by weight of the total monomer mixture was slowly charged into the reactor at a specified charging rate over a predetermined charging time from about 4 minutes to about 11 minutes. The addition of these monomers was carried out in a programmed batch and / or semi-batch mode, and the amount of a polarity regulator (randomizing agent) was adjusted to about 0.002 to about 0.013% by weight of the total reaction mixture in order to promote the formation of a statistically distributed tapered S / B copolymer block in which the composition and vinyl microstructure (1,2-addition) along the copolymer chain gradually changed. Thereafter, this second polymerization step was allowed to proceed adiabatically to complete conversion, and the final peak temperature (Tp) was increased to about 100 to about 105 °C, thereby forming a counter-tapered copolymer [A / B] block, and thus, a living counter-tapered A-[A / B] diblock copolymer having a peak molecular weight Mp with a target value from about 104,000 to about 122,000 was obtained.

[0094] Finally, a sufficient amount of a suitable coupling agent such as silicon tetrachloride (SiCl4) from about 0.003 to about 0.008 of the total reaction mixture was added to the reactor to partially couple the living counter-tapered A-[A / B] diblock copolymer to obtain a desired ratio of the uncoupled linear diblock A-[A / B] to the coupled radial (A-[A / B])n-X counter-tapered thermoplastic elastomer composition of the present invention. In the formula, X is the remaining part (Si) of the coupling reaction process. The remaining living polymer chains were terminated by adding a stoichiometrically 10 mol% excess of a suitable alcohol to the final reaction mixture.

[0095] Tables 1 and 2 show the results of the analytical property evaluations of the novel counter-tapered thermoplastic elastomer compositions CTTE1 to 19. The average molecular weights (Mp and Mw) are all shown in units of 1000 (k) and were calculated by conversion to polystyrene standards using GPC. The peak average molecular weight Mp of the monovinyl aromatic homopolymer block A or polystyrene block of CTTE1 to 14 and 17 was from about 9.5 to about 11 kg / mol. The peak average molecular weight Mp of the A-[A / B] diblock copolymer or S-[S / B] styrene-butadiene diblock copolymer of CTTE1 to 14 and 17 was from about 104 to about 122 kg / mol. The peak average molecular weight Mp of the [A / B] counter-tapered copolymer or [S / B] styrene-butadiene copolymer of CTTE15, 16, 18, and 19 was from about 94 to about 108 kg / mol. The ratio of the Mp of the coupled radial (A-[A / B])n-X to the Mp of the uncoupled linear diblock A-[A / B] of CTTE1 to 14 and 17 was from about 3.3 to about 3.5. The weight average molecular weight Mw of CTTE1 to 14 and 17 was from about 178 to about 267 kg / mol. The ratio of the uncoupled linear diblock A-[A / B] to the coupled radial (A-[A / B])n-X of CTTE1 to 14 and 17 was from about 0.6 to about 2.8. This is the coupling efficiency determined from the GPC area. The vinyl [A / B] block content of CTTE1 to 19 was from about 13.7 to about 33.0 wt% based on the total butadiene units. The glass transition temperatures of the [A / B] counter-tapered copolymer blocks of CTTE6, 9, and 14 to 19 were from about -82.0 to about -71.9 °C. For CTTE1 to 14 and 17, the following contents were determined by NMR: the total styrene based on the total copolymer was from about 23.2 to about 25.4 wt%; the block styrene based on the total styrene units was from about 68.8 to about 83.6 wt%; the intermediate block styrene based on the intermediate block copolymer was from about 7.9 to about 10.7 wt%, and the block degree of the intermediate block based on the intermediate block styrene units was from about 12.1 to about 55.1 wt%.

[0096] Figures 1, 2, 3, and 4 show the monomer distributions of the [A / B] intermediate block segments of the counter-tapered block copolymers CTTE 14, 16, 17, and 19 of the present invention prior to coupling. This was made possible by taking aliquots over the course of the copolymerization and then performing NMR characterization. In the case of CTTE 16 and 19, the first addition of styrene monomer was not performed in order to isolate the styrene / butadiene counter-tapered copolymer blocks and to directly analyze by 1H NMR the monomer distribution along the copolymer chains of the [A / B] intermediate block segments without performing the calculations necessary to subtract the monovinyl aromatic homopolymer blocks A (PS blocks) in CTTE 14 and 17. The monomer distributions of CTTE 14 and 17 were calculated according to the method used to characterize the polymer intermediate or “B” block described in U.S. Patent Application Publication No. 2003 / 0176582A1, published Sep. 18, 2003, by KRATON Polymers U.S. LLC and Bening et al.

[0097] Figures 1 and 2 clearly show that the cumulative composition of the incorporated styrene monomer in the [A / B] intermediate block segment of CTTE 14 and 16 gradually decreases as the conversion of butadiene / styrene intermediate block polymerization increases. After coupling, this [A / B] intermediate block segment forms a complete [A / B]-X-[B / A] intermediate block with a terminal region rich in styrene monomer units (low butadiene / styrene cumulative ratio) and a central region rich in butadiene monomer units (high butadiene / styrene cumulative ratio), which is exactly the opposite of the prior art distribution control composition. This is a surprising and unexpected result considering both the fact that relatively little styrene monomer was present during the copolymerization of the intermediate block segment (about 10 wt% of the monomer mixture) and a sufficient amount of a polarity regulator (randomizing agent) for preparing the intermediate vinyl styrene / butadiene copolymer was used (about 30 wt% vinyl) in these copolymerizations. In addition, the counter-tapered A-[A / B]X-[B / A]-A thermoplastic elastomer composition of the present invention has a unique combination of high styrene (low butadiene / styrene ratio) and high vinyl at the terminal region of the complete [A / B]X-[B / A] styrene / butadiene intermediate block near the interface with the monovinyl aromatic homopolymer block A or polystyrene block. It is important to note that even though the terminal region of the styrene / butadiene intermediate block is styrene-rich (low butadiene / styrene cumulative ratio), a low level of blockiness of the intermediate block can be achieved. Also, it has been shown that the incorporation of styrene into the counter-tapered [A / B] intermediate block segment depends not only on the amounts of styrene monomer and randomizing agent, but also on the temperature profile of the copolymerization and the monomer feed time. Figures 2 and 3 show that the incorporation of styrene into the copolymer chain of the [A / B] intermediate block segment of CTTE 16 decreases more gradually in response to a longer feed time of the butadiene monomer. Figure 4 shows that when the amount of the polarity regulator (randomizing agent) is relatively lower (lower vinyl), the incorporation of styrene in the [A / B] intermediate block segment changes more dramatically between CTTE 17 and CTTE 19 in response to changes in the butadiene monomer feed time.

[0098]

Table 2

[0099]

Table 3

[0100]

Table 4

[0101] One embodiment of the present invention is a method of making a counter-tapered thermoplastic elastomer composition, comprising adding a solvent, a polarity modifier or a combination of polarity modifiers, and a monovinyl aromatic monomer to a reactor to form an initial reaction mixture, wherein the amount of the polarity modifier in the initial reaction mixture is less than 10% by weight; adding an organolithium initiator compound to the reactor and anionically polymerizing the monomer to form a monovinyl aromatic homopolymer block A having a peak molecular weight of at least 5,000; adding additional monovinyl aromatic monomer and simultaneously starting the introduction of a conjugated diene monomer into the reactor at a predetermined feed rate over a predetermined time and copolymerizing to form a counter-tapered copolymer block A / B having a vinyl content of at least 15 weight percent based on the amount of conjugated diene units in the diblock copolymer, and obtaining a counter-tapered diblock A-A / B copolymer having a peak molecular weight from 20,000 to 250,000; and adding a coupling agent or a combination of coupling agents to partially couple the counter-tapered diblock A-A / B copolymer to form a block copolymer that is either a linear triblock copolymer, a multi-arm coupling block copolymer, or a mixture thereof, wherein the solvent, the polarity modifier, the conjugated diene monomer, and the monovinyl aromatic monomer constitute the total reaction mixture, the amount of the polarity modifier is less than 5% by weight of the total reaction mixture, the peak molecular weight of the linear triblock copolymer is at least about 1.5 times the peak molecular weight of the counter-tapered diblock A-A / B copolymer, the peak molecular weight of the multi-arm coupling block copolymer is at least about 2.5 times the peak molecular weight of the counter-tapered diblock A-A / B copolymer, and the ratio of the counter-tapered diblock A-A / B copolymer to the block copolymer is from about 1:5 to about 5:1 of the counter-tapered thermoplastic elastomer composition.

[0102] One embodiment of the present invention based on Example 1 and Table 3 is a method for producing a counter-tapered thermoplastic elastomer in either batch or semi-batch mode, Preferably and optionally, purifying the solvent and monomer to reduce their water content to a maximum of 50 ppm, preferably less than 25 ppm, more preferably less than 5 ppm; Placing the solvent into the reactor and heating the solvent to an initial reaction temperature (Ti) of 50 - 75 °C, optionally 55 - 70 °C, preferably 55 - 70 °C, more preferably 60 - 66 °C, where the solvent exceeds 75 wt% of the total reaction mixture, preferably 80 - 90 wt%, more preferably 84 - 90 wt%, most preferably 86 - 89 wt%, with values of 86 and 88 wt% being typical, and the solvent being preferably cyclohexane; Preferably, adding a suitable polarity regulator to the reactor, where the suitable polarity regulator is preferably ditetrahydrofuranylpropane (DTHFP) or tetrahydrofuran (THF), more preferably DTHFP; Adding a monovinyl aromatic monomer to the reactor, where the monovinyl aromatic monomer is preferably styrene and typically 15 - 20 wt%, preferably 16 - 19 wt%, more preferably 17 - 18 wt% of the total monomer mixture, with 17.5 wt% being most preferred; Preferably and optionally, enabling stabilization of the solvent, polarity regulator, and monovinyl aromatic monomer at Ti plus or minus 10 °C, preferably plus or minus 5 °C, more preferably plus or minus 2 °C, with stabilization at Ti being most preferred; Adding a lithium-based initiator, preferably n-butyllithium, in a suitable solvent solution to the reactor mixture, preferably where the amount of the initiator is stoichiometrically calculated to form individual blocks and compensate for impurities; Enable the reaction to proceed, preferably and optionally, to complete conversion, preferably to at least 90% conversion, more preferably to at least 95% or more conversion, and optionally form a monovinyl aromatic homopolymer block A having a peak molecular weight Mp of 5 to 15 kg / mol, preferably having a peak molecular weight of 8 to 12 kg / mol, more preferably having a peak molecular weight of 10 to 11 kg / mol; Preferably, a second addition of the monovinyl aromatic monomer is typically 5 to 15% by weight, preferably 6 to 12% by weight, more preferably 7 to 9.5% by weight, most preferably 7.5 to 9.1% by weight of the total monomer mixture, preferably styrene, and 7.5% by weight of the total monomer mixture is a preferred value, preferably styrene, is generally added to the reactor within a period of 5 minutes, preferably in less than 2 minutes; Charge the conjugated diene monomer B into the reactor, preferably without an initial addition of the conjugated diene monomer and preferably without setting a waiting time after the initial addition of the conjugated diene. The total amount of the charged conjugated diene monomer exceeds 55% by weight of the total monomer mixture, typically 60 to 90% by weight, generally 65 to 85% by weight, preferably 70 to 80% by weight, and 75% by weight of the total monomer mixture is a preferred amount, The conjugated diene monomer is charged at a feed rate of 20 to 75 g / min, often at a feed rate of 30 to 70 g / min, generally at a feed rate of 45 to 68 g / min, usually at a feed rate of 47 to 67 g / min, preferably at a feed rate of 54 to 67 g / min, The time during which the conjugated diene monomer is charged is less than 90, 80, 70, 60, 50, 40, 30, 20, or 15 minutes, generally less than 13 minutes, preferably within a period of 4 to 12 minutes, more preferably within 5 to 11 minutes. Preferably, the conjugated diene is butadiene or isoprene, more preferably 1,3-butadiene; The reaction proceeds to at least 80% conversion, generally to more than 90% conversion, preferably to at least 98% conversion, more preferably to at least 99% conversion, most preferably to complete conversion, preferably at a final peak temperature Tp above 100 °C, more preferably between 103 and 106 °C or between 103 and 105 °C, thereby enabling the formation of a counter-tapered copolymer block A / B, preferably in a single reactor, preferably without the need to use two reactors, to obtain a living counter-tapered diblock A-A / B copolymer, and usually the peak molecular weight of the counter-tapered diblock A-A / B copolymer is between 70 and 140 kg / mol, preferably the peak molecular weight of the counter-tapered diblock A-A / B copolymer is between 80 and 130 kg / mol, more preferably the peak molecular weight of the counter-tapered diblock A-A / B copolymer is between 90 and 125 kg / mol, and the range of 100 to 115 kg / mol is the most typical, which is a method including the above.

[0103] An optional but preferred next step is preferably carried out in the same reactor without transferring to a second reactor. Adding a suitable coupling agent or combination of coupling agents, preferably silicon tetrachloride, to the reactor to partially couple the living counter-tapered diblock A-A / B copolymer to form a counter-tapered thermoplastic elastomer, and the amount of the coupling agent is 0.0020 to 0.0100 wt% of the total reaction mixture, generally 0.0025 to 0.0085 wt%, preferably 0.0030 to 0.0080 wt%. Usually, the ratio of the uncoupled linear diblock A-[A / B] to the coupled radial (A-[A / B])n-X counter-tapered thermoplastic elastomer is between 0.2 and 5.0, preferably the ratio is between 0.3 and 4.0, more preferably the ratio is between 0.5 and 3.0 or between 0.4 and 3.0. Generally, the weight-average molecular weight Mw of the above counter-tapered thermoplastic elastomer is 80 to 300 kg / mol, generally 85 to 275 kg / mol, preferably 90 to 270 kg / mol, more preferably 95 to 267 kg / mol, Generally, the A / B-X-B / A intermediate block formed after coupling has a central region having a cumulative ratio of butadiene units to styrene units, and the cumulative B / S ratio is at least 3, preferably at least 5, more preferably at least 10.

[0104] Referring to Table 2 and the above-described embodiments, the coupled CTTEs 1 to 14 have a total monovinyl aromatic monomer content of 15 to 35% by weight, generally 20 to 30% by weight, preferably 22 to 28% by weight, more preferably 23 to 26% by weight, preferably styrene, and the balance is a conjugated diene monomer, preferably butadiene. Usually, the coupled CTTEs contain 20 to 30% by weight of monovinyl aromatic monomer units and 70 to 80% by weight of conjugated diene monomer units, preferably 22 to 28% by weight of monovinyl aromatic monomer units and 72 to 78% by weight of conjugated diene monomer units, more preferably 23 to 26% by weight of monovinyl aromatic monomer units and 74 to 77% by weight of conjugated diene monomer units. Further, in the above embodiments, a linear diblock A-[A / B] in which the terminal B portion is living is formed, and the coupling agent binds to the living terminal B portion, and at least two of the linear diblock A-[A / B] units are coupled together to form (A-[A / B])-X-([B / A]-A) and / or a coupled radial (A-[A / B])n-X counter-tapered thermoplastic elastomer. After coupling, the CTTE has a central block containing units of both a monovinyl aromatic monomer, preferably styrene, and a conjugated diene monomer, preferably butadiene, and end blocks that are homopolymers of a monovinyl aromatic monomer, preferably polystyrene. The intermediate block is the [A / B]-X-[B / A] portion, and this portion may be a combination of linear and radial units depending on whether two or more [A / B] units bind to the coupling agent.This intermediate block portion of Table 2 is 2 to 20% by weight of a monovinyl aromatic monomer, preferably styrene, and 80 to 98% by weight of a conjugated diene monomer, preferably butadiene. Usually, it is 5 to 15% by weight of a monovinyl aromatic monomer, preferably styrene, and 85 to 95% by weight of a conjugated diene monomer, preferably butadiene. Preferably, it is 6 to 12% by weight of a monovinyl aromatic monomer, preferably styrene, and 88 to 94% by weight of a conjugated diene monomer, preferably butadiene. Most preferably, it is 7 to 11% by weight of a monovinyl aromatic monomer, preferably styrene, and 89 to 93% by weight of a conjugated diene monomer, preferably butadiene. The block degree of the intermediate blocks of CTTE1 to 14 shown in Table 2 is in the range of 10 to 60% by weight, generally in the range of 10 to 56% by weight, preferably 10 to 45% by weight.

[0105] In addition to the above embodiments, referring to FIGS. 1-4 and Table 2, and the coupled CTTEs 1-14 and 17, a linear diblock A-[A / B] is formed in which the terminal B portion is living, and the coupling agent binds to the living terminal B portion, and at least two of the linear diblock A-[A / B] units are coupled together to form (A-[A / B])-X-([B / A]-A) and / or a coupled radial (A-[A / B])n-X counter-tapered thermoplastic elastomer. After coupling, the CTTE has a central block containing units of both a monovinyl aromatic monomer, preferably styrene, and a conjugated diene monomer, preferably butadiene, and end blocks that are homopolymers of a monovinyl aromatic monomer, preferably polystyrene. The intermediate block is the [A / B]-X-[B / A] portion, which may be a combination of linear and radial units depending on whether two or more [A / B] units are coupled to the coupling agent. FIGS. 1-4 show the monomer distribution along the copolymer chain of the [A / B]-X-[B / A] portion of the intermediate block before coupling of CTTEs 14, 16, 17, and 19, showing that the intermediate block has a terminal region rich in styrene monomer units (low butadiene / styrene cumulative ratio) and a central region rich in butadiene monomer units (high butadiene / styrene cumulative ratio). CTTE 14 has a butadiene / styrene B / S cumulative ratio of about 16.0 mol / mol for about 10.7 wt% intermediate block styrene, CTTE 16 has a butadiene / styrene B / S cumulative ratio of about 15.1 mol / mol for about 11.3 wt% intermediate block styrene, CTTE 17 has a butadiene / styrene B / S cumulative ratio of about 18.1 mol / mol for about 9.6 wt% intermediate block styrene, and CTTE 14 has a butadiene / styrene B / S cumulative ratio of about 16.7 mol / mol for about 10.3 wt% intermediate block styrene. The CTTE butadiene / styrene B / S cumulative ratio of the intermediate block portion in Table 2 is from 5 to 30 mol / mol, generally from 8 to 25 mol / mol, preferably from 10 to 23 mol / mol, and most preferably from 12 to 21 mol / mol.Typically, the A / B-X-B / A intermediate block formed after coupling has a central region with a cumulative ratio of butadiene units to styrene units, and the cumulative B / S ratio is at least 3, preferably at least 5, more preferably at least 10.

[0106] Embodiments of the present invention 1. A method for producing a counter-tapered thermoplastic elastomer composition, comprising: Putting a solvent into a reactor, heating the solvent to an initial reaction temperature (Ti) of preferably 50 to 75 °C, the amount of the solvent being preferably more than 75% by weight of the total reaction mixture, and the solvent being preferably cyclohexane; Adding a polarity regulator to the reactor, the polarity regulator being preferably ditetrahydrofuranylpropane (DTHFP) or tetrahydrofuran (THF); Adding a first amount of a monovinyl aromatic monomer to the reactor, the monovinyl aromatic monomer being preferably styrene, and the first amount of the monovinyl aromatic monomer being preferably 15 to 20% by weight of the total monomer mixture; Adding a lithium-based initiator to the mixture in the reactor; Forming a monovinyl aromatic homopolymer block A by allowing the reaction to proceed, the peak molecular weight Mp of block A being preferably 5 to 15 kg / mol; Adding a second amount of the monovinyl aromatic monomer or another monovinyl aromatic monomer to the reactor, the second amount of the monovinyl aromatic monomer being preferably 2 to 15% by weight of the total monomer mixture, and the second amount being preferably added within a period of 5 minutes, more preferably less than 2 minutes; Feeding a conjugated diene monomer B into the reactor, preferably without an initial addition of the conjugated diene monomer and preferably without setting a waiting time after the initial addition of the conjugated diene, the total amount of the conjugated diene monomer fed being preferably more than 55% by weight of the total monomer mixture, more preferably 55 to 90% by weight; The conjugated diene monomer is preferably introduced at an input rate of 20 to 75 g / min, the time during which the conjugated diene monomer is administered is preferably less than 55 minutes, more preferably less than 25 minutes; a method that enables the reaction to proceed to at least 75% conversion, preferably to a final peak temperature Tp exceeding 80 °C, thereby preferably forming a counter-tapered copolymer block A / B in a single reactor and preferably without the need to use two reactors, obtaining a living counter-tapered diblock A-A / B copolymer, and the peak molecular weight of the counter-tapered diblock A-A / B copolymer being preferably 50 to 200 kg / mol.

[0107] A coupling agent, which may be a single coupling agent, a combination of coupling agents, an acrylic oligomer, or a combination thereof, is added to the reactor to preferably partially couple the living counter-tapered diblock A-A / B copolymer in the same reactor, preferably without transferring it to a second reactor, to form a counter-tapered thermoplastic elastomer, the amount of the coupling agent being preferably 0.0005 to 0.0500% by weight of the total reaction mixture, the ratio of uncoupled linear diblock A-[A / B] to coupled radial (A-[A / B])n-X counter-tapered thermoplastic elastomer is preferably 0.1 to 10.0, the weight average molecular weight Mw of the counter-tapered thermoplastic elastomer is preferably 30 to 1,000 kg / mol, a method for producing the counter-tapered thermoplastic elastomer composition of Embodiment 1, wherein the A / B-X-B / A intermediate block formed after coupling preferably has a central region having a cumulative ratio of butadiene units to styrene units, and the cumulative B / S ratio is generally at least 1, usually at least 2.5, preferably at least 5, and more preferably at least 10.

[0108] 3. A method for producing the counter-tapered thermoplastic elastomer composition of Embodiment 1 or 2, wherein the total monovinyl aromatic monomer content of the final product is preferably 10 to 48% by weight.

[0109] 4. A method for producing the counter-tapered thermoplastic elastomer composition of Embodiment 1, 2 or 3, for the coupled CTTE, wherein the total monovinyl aromatic monomer content of the coupled CTTE is preferably 10 to 40% by weight, and the coupled CTTE preferably contains 60 to 90% by weight of conjugated diene monomer units.

[0110] 5. A method for producing the counter-tapered thermoplastic elastomer composition of any one of Embodiments 1 to 4, for the coupled CTTE, wherein the intermediate block portion of the CTTE is preferably 2 to 20% by weight of monovinyl aromatic monomer and preferably 80 to 98% by weight of conjugated diene monomer, and the block degree of the intermediate block is preferably in the range of 5 to 75% by weight.

[0111] Example 2 Application in polymer-modified asphalt (PMA) for road paving The low Mw counter-tapered thermoplastic elastomers (CTTE1-7) of Tables 1 and 2, prepared as described in Example 1, were used as an asphalt modifier or asphalt strengthener for polymer-modified asphalt (PMA) for road paving formulations. To achieve this purpose, PG64-22 unmodified asphalt (provided by PEMEX) was formulated by a hot mix and high shear rate process. In this process, a three-axial high shear mill was used. First, the unmodified asphalt was heated to 120 °C in a nitrogen atmosphere without stirring to soften the asphalt. During this stage, very slow stirring was used to prevent asphalt overheating and oxidation. Once the asphalt was softened, heating was continued to 190 °C + / - 5 °C and the mixer stirring was increased to 2500 RPM. Once 190 °C was reached, the counter-tapered thermoplastic elastomer (CTTE) composition was gradually added to the asphalt at a rate of approximately 10 g / min. Stirring was maintained for 120 - 180 minutes to effectively and completely disperse the CTTE as a strengthener. To ensure that the same level of dispersion was achieved in all formulations, fluorescence microscopy using a Zeiss microscope model Axiotecy20X was used to monitor the CTTE dispersion in the asphalt.

[0112] The CTTE polymer-modified asphalt (PMA) mixture thus obtained was characterized by the ring and ball softening point temperature (TRBSP) in accordance with ASTM D36. The penetration was measured at 25 °C, for 10 seconds, and with 100 grams using a Koheler Penetrometer model K95500 in accordance with ASTM D5. The maximum application temperature ("maximum use T") was measured as the temperature at which the rutting factor or dynamic shear stiffness (G * / sinδ) takes a value of 1.0 kPa, where G *is the complex elastic modulus, and sinδ is the phase angle compliant with AASHTO TP5 by using a Paar Physica rheometer MCR-300-SP type. The AASHTO SUPERPAVE performance grade PG was determined. The kinematic viscosity at 135°C was measured in accordance with ASTM D4402 by using a Brookfield viscometer model RDVS-II+. The elastic recovery at 25°C in torsion mode was measured in accordance with AASHTO-TF31R. The elastic recovery at 25°C and the ductility at 4°C were measured by using an extensometer.

[0113] The results of CTTE polymer-modified asphalt (CTTE1-7PMA) are shown in Table 2a below, indicating that the performance of a novel counter-tapered thermoplastic elastomer composition as an asphalt modifier for road paving is high at a CTTE polymer content of 2.2 wt% based on the total PMA mixture.

[0114]

Table 5

[0115] Looking at Table 2a, these results show significantly low viscosity, high elastic response, a wide range of PG polymer-modified asphalt, and a good balance between high-temperature and low-temperature properties. The very low viscosity of the asphalt formulation contributes to facilitating the dispersion of the polymer in the asphalt, improving the time required for mixing, and in addition, by improving the pumpability and / or reducing the energy required to do so, it also makes the processing, handling, and construction of the modified asphalt mixture easier. This also means significant cost reduction and a more environmentally friendly process.

[0116] Example 3 Application in polymer-modified emulsion (PME) for road paving The low Mw counter-tapered thermoplastic elastomers (CTTE3 - 6) in Tables 1 and 2, prepared as described in Example 1, were used as an asphalt modifier or asphalt strengthener for the polymer-modified emulsion (PME) for road paving formulations. First, as described in Example 2, the PMA mixtures of each CTTE composition were prepared. Next, first, deionized water was heated to 45°C, and then approximately 0.5 wt% of a polyamine-type emulsifier (Redicote E4819, commercially available from Akzo Nobel) was gently added to the heated water with stirring, and then approximately 0.4 wt% of concentrated mineral acid (HCl, 37%) was added to prepare an aqueous emulsifier solution. This aqueous solution was stirred until the emulsifier was completely dissolved. The acidity was in the pH range of 2.0 ± 0.1, and it was ready for emulsification of the PMA mixture as it was. Finally, the emulsification process was carried out in the atmosphere by using an IKA colloid mill. Both the PMA mixture at 150°C and the aqueous emulsifier solution at 40°C (65:35 weight:weight) were pumped into the colloid mill operated at 90°C to form a polymer-modified asphalt emulsion (PME). Then, the newly prepared PME was placed in an oven at 80°C for 16 hours. After cooling to ambient temperature, the PME was passed through a 20-mesh copper sieve, and the amount of sieve residue was tested. Then, the polymer-modified asphalt emulsion (PME) thus obtained was processed to separate water and the residual PMA mixture was recovered.

[0117] The CTTE polymer-modified asphalt emulsion (PME) thus prepared was tested for 20-mesh sieve residue, Saybolt Furol viscosity at 50°C, and storage stability for 5 days. After separating water from the PME, the residual PMA mixture was characterized by the ring-and-ball softening point temperature (TRBSP) according to ASTM D36. The penetration was measured at 25°C, for 10 seconds, and with 100 grams using a Koheler Penetrometer K95500 type in accordance with ASTM D5. The elastic recovery at 25°C and the ductility at 4°C were measured by using an extensometer.

[0118] The results of the CTTE polymer-modified asphalt emulsion (CTTE3 - 6 PME) are shown in Table 3a below, indicating the high performance of the novel counter-tapered thermoplastic elastomer composition as an asphalt modifier for road paving.

[0119]

Table 6

[0120] Looking at Table 3a, the results of PME show low viscosity, good storage stability, and an acceptable sieve residue. Also, the results of PMA show a similar high elastic response before and after the emulsification process (raw material and residue), and an excellent balance between high-temperature and low-temperature properties.

[0121] Example 4 Preparation of Counter-Tapered Thermoplastic Elastomer (CTTE) In Example 4, several novel counter-tapered thermoplastic elastomers (CTTE20 - 38) were prepared according to the method claimed in the present invention. The polymers CTTE20 - 38 are (A - [A / B])n - X block copolymers, where the A - [A / B] diblock before coupling consists of a monovinyl aromatic homopolymer block A block which is a polystyrene block (PS), and a counter-tapered copolymer block [A / B] which is a styrene / butadiene copolymer block. After coupling, an [A / B] - X - [B / A] intermediate block with a styrene unit-rich terminal region and a butadiene unit-rich central region was formed. CD1 and CD2 were comparative examples of prior art distribution control block copolymers prepared according to procedures similar to those described in U.S. Patent Application Publication No. 2003 / 0176582A1, published on September 18, 2003, by KRATON Polymers U.S. LLC and Bening et al. CD2 was a polymer prepared using only the controlled distribution copolymer block [B / A] of styrene / butadiene to illustrate the monomer distribution of the intermediate copolymer chain before coupling.

[0122] These novel counter-tapered thermoplastic elastomer (CTTE20-38) compositions were characterized by GPC, 1H NMR, and DSC methods to determine the following: the peak molecular weight (Mp), weight average molecular weight (Mw), and molecular weight average and molecular weight distribution characteristics such as diblock coupling ratio of linear diblock and coupling modes; the microstructure characteristics such as total styrene, block styrene, and vinyl A / B block content; the glass transition temperature (Tg) of the A / B counter-tapered copolymer block; and the melt flow rate (MFI) of the CTTE counter-tapered thermoplastic elastomer composition. In addition, the calculation of the intermediate block styrene and the block degree of the intermediate block was carried out according to the methods used to characterize the polymer intermediate or "B" block, such as Calc.Mid PSC and Calc.Mid Blocky described in U.S. Patent Application Publication No. 2003 / 0176582A1 published on September 18, 2003 by KRATON Polymers U.S. LLC and Bening et al. Tables 4-5 show the results of the analytical characterization, and Table 6 shows the polymerization conditions of CTTE20-38 and CD1-2. Described below is a basic procedure similar to that described in Example 1 used to prepare these novel counter-tapered thermoplastic elastomers (CTTE20-38) and to control the monomer distribution in the anionic copolymerization of 1,3-butadiene (B) and styrene (S) in the presence of ditetrahydrofuranylpropane (DTHFP) or tetrahydrofuran (THF) as a suitable polarity regulator and randomizing agent for the styrene / butadiene [S / B] counter-tapered copolymer block. The abbreviations used for the polymerization conditions in Table 6 below are defined as follows: CHx = cyclohexane; STY = styrene; and BD = 1,3-butadiene. For the novel counter-tapered thermoplastic elastomers CTTE20-32 and 37-38 and further the CD1 comparative example, silicon tetrachloride (SiCl4) was used as a coupling agent. For CTTE33-36, an acrylic oligomer similar to that described in U.S. Patent No. 8,981,008 was used as a coupling agent.

[0123] The novel counter-tapered thermoplastic elastomer (CTTE20-38) compositions of the present invention and distribution control comparative examples CD1-2 were prepared in a 7.57 liter reactor system operated in batch and / or semi-batch mode under an inert nitrogen atmosphere according to the teachings of the present invention. Immediately prior to addition to the reactor system, the solvents and monomers were thoroughly purified by flowing them through a set of columns filled with alumina and molecular sieves, reducing their moisture content to a maximum of 5 ppm. In the first polymerization step, an appropriate amount of purified solvent (CHx) was charged to the reactor and heated to an initial reaction temperature (Ti) of about 50 °C. Ti was set at a lower temperature of about 30 °C for the CD1 polymer. Once Ti was reached, a suitable polarity regulator (randomizing agent) such as ditetrahydrofuranylpropane (DTHFP) or tetrahydrofuran (THF) was added to the reactor, followed by the first addition (first STY) of monovinyl aromatic monomer from about 17.5 wt% to about 30.0 wt% of the total monomer mixture. In the case of CD1, the first addition (first STY) of monovinyl aromatic monomer of about 27 wt% of the total monomer mixture was the same as that of CTTE37-38 in order to directly compare and distinguish the inventors' compositions / methods from the prior art. In the case of CD2, the first addition of styrene monomer was not carried out in order to directly analyze by 1H NMR the isolated styrene / butadiene counter-tapered copolymer block without performing the calculations necessary to remove the interference with the monovinyl aromatic homopolymer block A (PS block) in CTTE20-38 and CD1, for the middle block styrene, the block degree of the middle block, and the monomer distribution along the copolymer chain of the [A / B] counter-tapered copolymer block. This was made possible by taking split amounts throughout the copolymerization and then performing NMR characterization. After stabilizing the reaction mixture at Ti, n-butyllithium or another suitable initiator in a suitable solvent solution was added directly to the reactor mixture containing an amount of polarity regulator necessary to efficiently initiate the anionic polymerization of at least the living polystyrene block. The amount of initiator was stoichiometrically calculated as described in the literature to form individual blocks having the desired molecular weight and to compensate for residual impurities.Thereafter, this first polymerization step was allowed to proceed adiabatically to complete conversion to form a monovinyl aromatic homopolymer block A having a peak molecular weight Mp in the target value range of from about 10,000 to about 20,000.

[0124] In the second polymerization step, in the case of CTTE 20 - 38, the addition of both monomers was started simultaneously. The addition of the second monovinyl aromatic monomer (second STY) at about 6.3 - about 22 wt% of the total monomer mixture was rapidly charged into the reactor at a specified charging rate from about 41 to 146 g / min over a predetermined charging time of about 1 minute. The addition of the conjugated diene monomer (BD) at about 50 - about 70 wt% of the total monomer mixture was slowly charged into the reactor at a specified charging rate from about 48 to 70 g / min over a predetermined charging time from about 6.5 to about 7 minutes. These monomer additions were carried out in a programmed batch and / or semi-batch mode. The amount of the polarity regulator (randomizing agent) was adjusted to about 0.01 to about 0.20 wt% of the total reaction mixture to promote the formation of a statistically distributed tapered S / B copolymer block in which the composition and vinyl microstructure (1,2-addition) along the copolymer chain gradually changed. Then, this second polymerization step was allowed to proceed adiabatically to complete conversion, increasing the final peak temperature (Tp) to about 96 to about 107 °C, thereby forming a counter-tapered copolymer [A / B] block, and thus obtaining a living counter-tapered A-[A / B] diblock copolymer having a peak molecular weight Mp with a target value from about 70,000 to about 213,000. In the second polymerization step of distribution control comparative examples CD1 - 2, the addition of the styrene monomer was started 1 minute after the addition of the butadiene monomer was started. Thus, the addition of the second monovinyl aromatic monomer (second STY) at about 22 - about 30 wt% of the total monomer mixture was slowly charged into the reactor at a specified charging rate from about 9 to 10 g / min over a predetermined charging time from about 15 to about 16 minutes. The addition of the conjugated diene monomer (BD) at about 50 - about 70 wt% of the total monomer mixture was very slowly charged into the reactor at a specified charging rate from about 10 to about 11 g / min over a predetermined charging time from about 31 to about 33 minutes.The addition of these monomers was carried out in a programmed batch and / or semi-batch mode, and the amount of the polarity regulator (randomizing agent) was adjusted to about 0.047 to about 0.048 wt% of the total reaction mixture to promote the formation of a statistically distributed tapered S / B copolymer block in which the composition and vinyl microstructure (1,2-addition) along the copolymer chain gradually change. Then, this second polymerization step was allowed to proceed adiabatically to complete conversion, increasing the final peak temperature (Tp) to about 80 to about 82 °C, thereby forming a distribution-controlled [B / A] block, and thus obtaining a living distribution-controlled A-[B / A] diblock copolymer having a peak molecular weight Mp in the target value range of about 95,000 to about 124,000.

[0125] Finally, a sufficient amount of a suitable coupling agent such as silicon tetrachloride (SiCl4) or acrylic oligomer, from about 0.0027 to about 0.032 of the total reaction mixture, was added to the reactor to partially couple the living counter-tapered A-[A / B] diblock copolymer to obtain the desired ratio of the uncoupled linear diblock A-[A / B] to the coupled radial (A-[A / B])n-X counter-tapered thermoplastic elastomer composition of the present invention. Wherein X is the remaining part of the coupling reaction process. The remaining living polymer chains were terminated by adding a 10 mol% excess of a suitable alcohol over stoichiometry to the final reaction mixture. The coupling of the distribution-controlled styrene / butadiene copolymer diblock of Comparative Example CD1 was carried out according to a similar procedure.

[0126] Tables 4 and 5 show the results of the analytical property evaluations of the novel counter-tapered thermoplastic elastomer compositions CTTE20 to 38. The average molecular weights (Mp and Mw) are all shown in units of 1000 (k) and were calculated by conversion to polystyrene standards using GPC. The peak average molecular weight Mp of the monovinyl aromatic homopolymer block A or polystyrene block of CTTE20 to 38 is from about 10.2 to about 19.8 kg / mol. The peak average molecular weight Mp of the A-[A / B] diblock copolymer or S-[S / B] styrene-butadiene diblock copolymer of CTTE20 to 38 is from about 70 to about 213 kg / mol. The peak average molecular weight Mp of the [B / A] distribution control copolymer or [B / S] styrene-butadiene copolymer of CD1 to 2 is from about 95 to about 124 kg / mol. The ratio of the Mp of the coupled radial (A-[A / B])n-X of CTTE20 to 38 to the Mp of the uncoupled linear diblock A-[A / B] is from about 3.1 to about 11.9. The weight average molecular weight Mw of CTTE20 to 38 is from about 179 to about 521 kg / mol. The ratio of the uncoupled linear diblock A-[A / B] of CTTE20 to 38 to the coupled radial (A-[A / B])n-X is from about 0.2 to about 3.2. This is the coupling efficiency determined from the GPC area. The vinyl [A / B] block content of CTTE20 to 38 is from about 18.5 to about 54.0 wt% based on the total butadiene units. The glass transition temperature of the [A / B] counter-tapered copolymer block of CTTE20 to 38 is from about -81.9 to about -47.8 °C. The melt flow rate (MFI) of the CTTE20 to 38 compositions is from about 0 (NF) to about 94.9 g / 10 min.For CTTE 20 to 38, the following contents were determined by NMR: The total styrene based on the total copolymer is from about 14.1 to about 49.5% by weight; the block styrene based on the total styrene units is from about 53.2 to about 91.0% by weight; the intermediate block styrene based on the intermediate block copolymer is from about 5.2 to about 34.4% by weight, and the block degree of the intermediate block based on the intermediate block styrene units is from about 6.6 to about 73.8% by weight.

[0127] Figure 5 shows the monomer distributions of the [A / B] intermediate block segments before coupling of the counter-tapered block copolymers CTTE 20, 37, and 38 of the present invention, and the monomer distributions of the [B / A] intermediate block segments before coupling of the comparative distribution control examples CD1 and 2. These were possible by taking split amounts over the entire copolymerization and then performing NMR characterization. In the case of CD2, in order to isolate the styrene / butadiene distribution control copolymer block and directly analyze by 1H NMR the monomer distribution along the copolymer chain of the [B / A] intermediate block segment without performing the calculations necessary to subtract the monovinyl aromatic homopolymer block A (PS block) in CTTE 37 - 38 and CD1, the first addition of styrene monomer was not performed. The monomer distribution calculations for CTTE 37 - 38 and CD1 were carried out according to the method used to characterize the polymer intermediate or "B" block described in U.S. Patent Application Publication No. 2003 / 0176582A1, published on September 18, 2003, by KRATON Polymers U.S. LLC and Bening et al.

[0128] Figure 5 clearly shows that the cumulative composition of the incorporated styrene monomer in the [A / B] intermediate block segment of CTTE 37 - 38 gradually decreases as the conversion of butadiene / styrene intermediate block polymerization increases. After coupling, this [A / B] intermediate block segment forms a complete [A / B]-X-[B / A] intermediate block with a terminal region rich in styrene monomer units (low butadiene / styrene cumulative ratio) and a central region rich in butadiene monomer units (high butadiene / styrene cumulative ratio). This is completely opposite to the prior art distribution control compositions, and it is more prominent in the inventors' comparative examples CD1 and CD2 of the distribution control compositions. This is a surprising and unexpected result considering both the fact that a relatively large amount of styrene monomer is present during the copolymerization of the intermediate block segment (about 30 wt% of the monomer mixture) and a relatively low amount of a polarity regulator (randomizing agent) is used for preparing a low vinyl styrene / butadiene copolymer (about 20 wt% vinyl) in such copolymerizations. Also, it is important to note that even if the terminal region of the styrene / butadiene intermediate block is rich in styrene (low butadiene / styrene cumulative ratio), a low level of blockiness of the intermediate block can be achieved. Also, it has been shown that the incorporation of styrene into the counter-tapered [A / B] intermediate block segment depends not only on the amount of styrene monomer and the amount and type of the randomizing agent, but also on the temperature profile of the copolymerization and the monomer feed time. Figure 5 shows that the incorporation of styrene into the copolymer chain of the [A / B] intermediate block segment of CTTE 37 and 38 is usually higher compared to CTTE 20. Also, Figure 5 shows that in the case where the amount of the polarity regulator (randomizing agent) is relatively low (low vinyl), in combination with the use of THF as the randomizing agent at a lower temperature, in response to a significant increase in the feed time of both butadiene and styrene monomers, the incorporation of styrene into the [B / A] intermediate block segment of CD1 and CD2 shows a more dramatic opposite change.

[0129]

Table 7

[0130]

Table 8

[0131]

Table 9

[0132] One embodiment of the present invention based on Example 4 and Table 6 is a method of making a counter-tapered thermoplastic elastomer in either batch or semi-batch mode, Preferably and optionally, purifying the solvent and monomer to reduce their water content to a maximum of 50 ppm, preferably less than 25 ppm, more preferably less than 5 ppm; Placing the solvent in a reactor and heating the solvent to an initial reaction temperature (Ti) of 40 - 65 °C, optionally 45 - 55 °C, preferably 47 - 53 °C, more preferably 48 - 52 °C and about 50 °C, where the solvent is more than 75 wt% of the total reaction mixture, preferably 80 - 95 wt%, more preferably 84 - 90 wt%, most preferably 85 - 87 wt%, with a value of about 85 or 86 wt% being typical, and the solvent is preferably cyclohexane; Preferably, adding a suitable polarity regulator to the reactor, where the suitable polarity regulator is preferably ditetrahydrofuranylpropane (DTHFP) or tetrahydrofuran (THF), more preferably DTHFP; Add a monovinyl aromatic monomer to the reactor, where the monovinyl aromatic monomer is preferably styrene and typically ranges from 10 to 35 wt%, preferably 15 to 33 wt%, more preferably 16 to 31 wt% of the total monomer mixture, and amounts of 17.5, 27.0, and 30.0 wt% are possible; preferably and optionally, enable the stabilization of the solvent, polarity regulator, and monovinyl aromatic monomer at a temperature of Ti plus or minus 10 °C, preferably plus or minus 5 °C, and more preferably plus or minus 2 °C, with stabilization at Ti being most preferred; Add a lithium-based initiator, preferably n-butyllithium, in a suitable solvent solution to the reactor mixture, and preferably, the amount of the initiator is stoichiometrically calculated to form individual blocks and compensate for impurities; Enable the above reaction to proceed preferably and optionally to complete conversion, preferably at least 90% conversion, more preferably 95% or more conversion, and optionally form a monovinyl aromatic homopolymer block A having a peak molecular weight Mp of 5 to 25 kg / mol, preferably having a peak molecular weight of 8 to 22 kg / mol, more preferably having a peak molecular weight of 10 to 20 kg / mol; Preferably, add a second portion of the monovinyl aromatic monomer, typically 5 to 25 wt%, preferably 6 to 22 wt% of the total monomer mixture, preferably styrene, and preferred values of 6.3, 12.4, 16.5, and 22.1 wt% of the total monomer mixture are possible, preferably styrene, generally within a period of 5 minutes, preferably less than 2 minutes, more preferably within a period of about 1 minute, to the reactor; Charge the conjugated diene monomer B to the reactor, preferably without an initial addition of the conjugated diene monomer and preferably without setting a waiting time after the initial addition of the conjugated diene, and preferably start simultaneously with the dosing of the second portion of the monovinyl aromatic monomer, and the total amount of the charged conjugated diene monomer exceeds 40 wt% of the total monomer mixture, typically 45 to 90 wt% of the total monomer mixture, generally 45 to 80 wt%, preferably 50 to 72 wt%; The above conjugated diene monomer is fed at a feed rate of 30 to 90 g / min, often at a feed rate of 35 to 80 g / min, generally at a feed rate of 45 to 75 g / min, preferably at a feed rate of 48 to 70 g / min, the time during which the above conjugated diene monomer is fed is less than 90, 80, 70, 60, 50, 40, 30, 20, or 15 minutes, generally less than 13 minutes, within a period of generally 4 to 12 minutes, preferably within 5 to 9 minutes, more preferably within 6.5 to 7 minutes, preferably, the above conjugated diene is butadiene or isoprene, more preferably 1,3-butadiene; the above reaction is allowed to proceed to at least 80% conversion, generally more than 90% conversion, preferably at least 98% conversion, more preferably at least 99% conversion, most preferably complete conversion, preferably at a final peak temperature Tp above 90 °C, more preferably 95 to 110 °C or 100 to 105 °C, thereby, preferably in a single reactor, preferably without the need to use two reactors, to form a counter-tapered copolymer block A / B and obtain a living counter-tapered diblock A-A / B copolymer. Usually, the peak molecular weight of the above counter-tapered diblock A-A / B copolymer is 60 to 230 kg / mol. Preferably, the peak molecular weight of the above counter-tapered diblock A-A / B copolymer is 65 to 220 kg / mol. More preferably, the peak molecular weight of the above counter-tapered diblock A-A / B copolymer is 70 to 215 kg / mol, and the range of 100 to 130 kg / mol is the most typical. This is a method including this.

[0133] The following step, which is optional but preferred, is preferably carried out in the same reactor without transferring to a second reactor, and a suitable coupling agent or combination of coupling agents, preferably silicon tetrachloride or an acrylic oligomer, is added to the reactor to partially couple the living counter-tapered diblock A-A / B copolymer to form a counter-tapered thermoplastic elastomer. The amount of the coupling agent is 0.0020 to 0.050% by weight, generally 0.0023 to 0.040% by weight, preferably 0.0025 to 0.0350% by weight of the total reaction mixture. Typically, the ratio of the uncoupled linear diblock A-[A / B] to the coupled radial (A-[A / B])n-X counter-tapered thermoplastic elastomer is 0.1 to 4.5, preferably the ratio is 0.1 to 4.0, more preferably the ratio is 0.2 to 2.7. Typically, the weight average molecular weight Mw of the counter-tapered thermoplastic elastomer is 100 to 500 kg / mol, generally 150 to 400 kg / mol, more preferably 170 to 375 kg / mol. Typically, the A / B-X-B / A intermediate block formed after coupling has a central region with a cumulative ratio of butadiene units to styrene units, and the cumulative B / S ratio is at least 3, preferably at least 5, more preferably at least 10.

[0134] Referring to Table 5 and the above-described embodiments, the coupled CTTEs 20 to 38 have a total monovinyl aromatic monomer, preferably styrene, in a content of 10 to 55% by weight, generally 14 to 50% by weight, preferably 17 to 45% by weight, more preferably 20 to 40% by weight, and the balance is a conjugated diene monomer, preferably butadiene. Usually, the coupled CTTEs contain 14 to 50% by weight of monovinyl aromatic monomer units and 50 to 86% by weight of conjugated diene monomer units, preferably 17 to 45% by weight of monovinyl aromatic monomer units and 55 to 83% by weight of conjugated diene monomer units, more preferably 20 to 40% by weight of monovinyl aromatic monomer units and 60 to 80% by weight of conjugated diene monomer units. Further in the above embodiments, a linear diblock A-[A / B] in which the terminal B portion is living is formed, and the coupling agent binds to the living terminal B portion, and at least two of the linear diblock A-[A / B] units are coupled together to form (A-[A / B])-X-([B / A]-A) and / or a coupled radial (A-[A / B])n-X counter-tapered thermoplastic elastomer. After coupling, the CTTE has a central block containing units of both a monovinyl aromatic monomer, preferably styrene, and a conjugated diene monomer, preferably butadiene, and end blocks that are homopolymers of a monovinyl aromatic monomer, preferably polystyrene. The intermediate block is the [A / B]-X-[B / A] portion, and this portion may be a combination of linear and radial units depending on whether two or more [A / B] units are bound to the coupling agent.This intermediate block portion of Table 5 is 4 to 40% by weight of a monovinyl aromatic monomer, preferably styrene, and 60 to 96% by weight of a conjugated diene monomer, preferably butadiene, and usually is 5 to 35% by weight of a monovinyl aromatic monomer, preferably styrene, and 65 to 95% by weight of a conjugated diene monomer, preferably butadiene, preferably is 5 to 32% by weight of a monovinyl aromatic monomer, preferably styrene, and 68 to 95% by weight of a conjugated diene monomer, preferably butadiene, and most preferably is 5 to 30% by weight of a monovinyl aromatic monomer, preferably styrene, and 70 to 95% by weight of a conjugated diene monomer, preferably butadiene. The block degree of the intermediate block of CTTE 20 to 38 shown in Table 5 is in the range of 5 to 80% by weight, generally in the range of 6 to 75% by weight, preferably 6 to 45% by weight.

[0135] In addition to the above embodiments, referring to FIGS. 5 and 4, and Table 4, a linear diblock A-[A / B] is formed in which the terminal B portion is living, and the coupling agent binds to the living terminal B portion, and at least two of the linear diblock A-[A / B] units are coupled together, and (A-[A / B])-X-([B / A]-A) and / or a coupled radial (A-[A / B])n-X counter-tapered thermoplastic elastomer is formed. After coupling, the CTTE has a central block containing units of both a monovinyl aromatic monomer, preferably styrene, and a conjugated diene monomer, preferably butadiene, and end blocks that are homopolymers of a monovinyl aromatic monomer, preferably polystyrene. The intermediate block is the [A / B]-X-[B / A] portion, which may be a combination of linear and radial units depending on whether two or more [A / B] units bind to the coupling agent. FIGS. 1-4 show the monomer distribution along the copolymer chain of the intermediate block [A / B]-X-[B / A] portion of CTTEs 37 and 38 prior to coupling, showing that the intermediate block has a terminal region rich in styrene monomer units (low butadiene / styrene cumulative ratio) and a central region rich in butadiene monomer units (high butadiene / styrene cumulative ratio). CTTE 37 has a butadiene / styrene B / S cumulative ratio of about 3.7 mol / mol for an intermediate block styrene of about 34.4 wt%, and CTTE 38 has a butadiene / styrene B / S cumulative ratio of about 3.7 mol / mol for an intermediate block styrene of about 34.3 wt%. The CTTE butadiene / styrene B / S cumulative ratio in the intermediate block portion of Table 4 is from 2 to 30 mol / mol, generally from 3 to 25 mol / mol, preferably from 3 to 23 mol / mol, and most preferably from 3 to 21 mol / mol. Usually, the A / B-X-B / A intermediate block formed after coupling has a central region having a cumulative ratio of butadiene units to styrene units, and the cumulative B / S ratio is at least 3, preferably at least 5, more preferably at least 10.

[0136] In addition to the comparative tests regarding the compositional and structural differences between the counter-tapered copolymer of the present invention and the control distribution copolymers of the prior art, next, the performance of the counter-tapered copolymer of the present invention in asphalt modification is compared with that of the control distribution copolymers of the prior art. The results of the asphalt / asphalt evaluation of the counter-tapered thermoplastic elastomer CTTE38 composition of the present invention compared with the control distribution CD1 comparative example of the prior art are shown in Table B below. The results of CTTE38 polymer-modified asphalt (CTTE38PMA) and CD1 polymer-modified asphalt (CD1PMA) are based on a polymer content of 4.0 wt% in the total PMA mixture, indicating that the performance of the novel counter-tapered thermoplastic elastomer composition as an asphalt modifier for road paving has been improved. The results of CTTE38PMA and CD1PMA show similar viscosities, softening points, ductilities, and elastic recoveries. The low viscosity of the asphalt blend contributes to promoting the dispersion of the polymer into the asphalt, improving the time required for mixing, improving the pumping capacity, and / or reducing the energy required for application, thereby facilitating the processing, handling, and construction of the modified asphalt mixture, which also means significant cost reduction and a more environmentally friendly process. Surprisingly, the results of CTTE38PMA and CD1PMA show that the range of the AASHTO SUPERPAVE performance grade PG of the counter-tapered CTTE38 polymer-modified asphalt of the present invention is unexpectedly wide and the balance between high-temperature and low-temperature properties is excellent when compared with the control distribution CD1 polymer-modified asphalt. The counter-tapered CTTE38 polymer-modified asphalt of the present invention shows an upper limit temperature (i.e., 88 °C) higher than the upper limit temperature of the control distribution CD1 polymer-modified asphalt (i.e., 82 °C). This is related to the highest temperature at which the asphalt can maintain sufficient rigidity to resist rutting. The counter-tapered CTTE38 polymer-modified asphalt of the present invention shows a lower limit temperature (i.e., -6 °C) similar to the lower limit temperature of the control distribution CD1 polymer-modified asphalt (i.e., -6 °C). This is related to the lowest temperature at which the asphalt can maintain sufficient flexibility to resist thermal cracking.

[0137]

Table 10

[0138] The counter-tapered CTTE38PMA of the present invention is characterized in that it has a better balance between processing characteristics and strengthening characteristics than the conventional control distribution CD1PMA. CTTE38 polymer-modified asphalt exhibits a more extensive and excellent AASHTO SUPERPAVE performance grade PG with the same viscosity, softening point, ductility, and elastic recovery as CD1 polymer-modified asphalt. AASHTO SUPERPAVE performance grade PG88-6 means that the CTTE38PMA of the present invention meets the criterion of the rutting factor or dynamic shear stiffness (G * / sinδ) of 1.0 kPa, which is the measured value of the minimum rigidity and elastic behavior required for polymer-modified asphalt (G * is the complex elastic modulus and sinδ is the phase angle) at high temperatures. 1 CTTE38 polymer-modified asphalt exhibits PG88-6, predicting that it has better pavement rutting performance, i.e., higher resistance to permanent deformation at high temperatures, than CD1 polymer-modified asphalt PG82-6. The better performance grade PG of the CTTE38 polymer-modified asphalt of the present invention is due to the combination of the novel counter-tapered A-[A / B] or S-[S / B] monomer distribution and microstructure characteristics of the present invention, i.e., a low styrene incorporation amount in the distal styrene of the A homopolymer block or S polystyrene block (high butadiene / styrene cumulative ratio), a high styrene incorporation amount in the proximal [A / B] or [S / B] intermediate block segment of the A homopolymer block or S polystyrene block (low butadiene / styrene cumulative ratio), a high vinyl content, and a low block degree of the intermediate block.

[0139] Embodiments of the present invention 6. A method for producing a counter-tapered thermoplastic elastomer composition, comprising Put the solvent into the reactor, heat the solvent to an initial reaction temperature (Ti) of preferably 50 to 75 °C, the amount of the solvent being preferably more than 75% by weight of the total reaction mixture, and the solvent being preferably cyclohexane; Add a polarity regulator to the reactor, the polarity regulator being preferably ditetrahydrofuranylpropane (DTHFP) or tetrahydrofuran (THF); Add a first amount of monovinyl aromatic monomer to the reactor, the monovinyl aromatic monomer being preferably styrene, and the first amount of monovinyl aromatic monomer being preferably 5 to 40% by weight of the total monomer mixture; Add a lithium-based initiator to the mixture in the reactor; By allowing the reaction to proceed, form a monovinyl aromatic homopolymer block A, the peak molecular weight Mp of block A being preferably 5 to 30 kg / mol; Add a second amount of the monovinyl aromatic monomer or another monovinyl aromatic monomer to the reactor, the second amount of monovinyl aromatic monomer being preferably 2 to 35% by weight of the total monomer mixture, and the second amount being preferably added within a period of 5 minutes, more preferably less than 2 minutes; Charge the conjugated diene monomer B into the reactor, preferably without an initial addition of the conjugated diene monomer and preferably without setting a waiting time after the initial addition of the conjugated diene, preferably starting simultaneously with the addition of the second amount of monovinyl aromatic monomer, the total amount of the charged conjugated diene monomer being preferably more than 35% by weight of the total monomer mixture, more preferably 40 to 95% by weight, The conjugated diene monomer being preferably charged at a charging rate of 20 to 95 g / min, The time during which the conjugated diene monomer is administered being preferably less than 45 minutes, more preferably less than 22 minutes; The method enables the reaction to proceed to at least 75% conversion and preferably to a final peak temperature Tp above 75 °C, thereby forming a counter-tapered copolymer block A / B, preferably in a single reactor and preferably without the need to use two reactors, to obtain a living counter-tapered diblock A-A / B copolymer, wherein the peak molecular weight of the counter-tapered diblock A-A / B copolymer is preferably from 40 to 400 kg / mol, more preferably from 50 to 300 kg / mol.

[0140] 7. A coupling agent may be a single coupling agent, a combination of coupling agents, an acrylic oligomer, or a combination thereof, which is added to the reactor to preferably partially couple the living counter-tapered diblock A-A / B copolymer, preferably in the same reactor and preferably without transferring it to a second reactor, to form a counter-tapered thermoplastic elastomer, wherein the amount of the coupling agent is preferably from 0.0005 to 0.0900% by weight of the total reaction mixture, The ratio of uncoupled linear diblock A-[A / B] to coupled radial (A-[A / B])n-X counter-tapered thermoplastic elastomer is preferably from 0.05 to 15.0, The weight average molecular weight Mw of the counter-tapered thermoplastic elastomer is preferably from 30 to 1,000 kg / mol, The A / B-X-B / A intermediate block formed after coupling preferably has a central region having a cumulative ratio of butadiene units to styrene units, wherein the cumulative B / S ratio is generally at least 1, usually at least 2.5, preferably at least 5, more preferably at least 10, a method for producing a counter-tapered thermoplastic elastomer composition of Embodiment 6.

[0141] 8. A method for producing the counter-tapered thermoplastic elastomer composition of embodiment 6 or 7, wherein the total monovinyl aromatic monomer content of the final product is preferably 5 to 75% by weight, more preferably 10 to 55% by weight.

[0142] 9. Regarding the coupled CTTE, a method for producing the counter-tapered thermoplastic elastomer composition of embodiment 6, 7 or 8, wherein the total monovinyl aromatic monomer content of the coupled CTTE is preferably 5 to 70% by weight, and the coupled CTTE preferably contains 30 to 95% by weight of conjugated diene monomer units.

[0143] 10. Regarding the coupled CTTE, a method for producing the counter-tapered thermoplastic elastomer composition of any one of embodiments 6 to 9, wherein the middle block portion of the coupled CTTE is preferably 2 to 60% by weight of monovinyl aromatic monomer and preferably 40 to 98% by weight of conjugated diene monomer, and the block degree of the middle block is preferably in the range of 5 to 80% by weight.

[0144] 11. A method for producing the counter-tapered thermoplastic elastomer composition of any one of embodiments 6 to 10, wherein the proportion of monovinyl aromatic monomer in the middle block decreases as the middle block is formed.

[0145] Example 5 Application in polymer-modified asphalt (PMA) for road paving The high Mw counter-tapered thermoplastic elastomer compositions (CTTE8 - 13) of Tables 1 and 2 prepared as described in Example 1 were used as asphalt modifiers or asphalt strengtheners for polymer-modified asphalt (PMA) for road paving formulations. The CTTE8 - 13 PMA formulations were prepared and characterized according to the procedure described in Example 2.

[0146] The results of CTTE polymer modified asphalt (CTTE8 - 13 PMA) are shown in Table 5a below, indicating high performance of a novel counter - tapered thermoplastic elastomer composition as an asphalt modifier for road paving at a CTTE polymer content of 2.2 wt% based on the total PMA mixture.

[0147]

Table 11

[0148] Looking at Table 5a, these results show low viscosity, higher elastic response, a wide range of PG polymer - modified asphalt, and an excellent balance between high - temperature and low - temperature properties. The combination of low viscosity and high elastic response of the asphalt formulations with the CTTE composition provides a desirable balance between processability and strengthening performance.

[0149] Example 6 Application in polymer - modified asphalt (PMA) for roofing materials and waterproof membranes The high Mw counter - tapered thermoplastic elastomer compositions (CTTE8 - 13) of Tables 1 and 2, prepared as described in Example 1, were used as an asphalt modifier or asphalt strengthener for polymer - modified asphalt (PMA) for roofing materials and waterproof membrane formulations. The CTTE8 - 13 polymer - modified asphalt (PMA) formulations were prepared according to the procedure described in Example 2.

[0150] The CTTE8 - 13 polymer - modified asphalt (PMA) mixtures thus obtained were characterized by the ring - and - ball softening point temperature (TRBSP) in accordance with ASTM D36. Penetration was measured at 60°C, for 10 seconds, and with 100 grams using a Koheler Penetrometer Model K95500 in accordance with ASTM D5. The kinematic viscosity at 160 and 190°C was measured in accordance with ASTM D4402 by using a Brookfield viscometer model RDVS - II +. The flexibility at low temperature was determined by measuring the BDA cold - bend temperature.

[0151] The results of CTTE polymer-modified asphalt (CTTE 8-13 PMA) are shown in Table 6a below, indicating high performance of a novel counter-tapered thermoplastic elastomer composition as an asphalt modifier for roofing materials and waterproof membranes at a CTTE polymer content of 8 wt% based on the total PMA mixture.

[0152] [Table 12]

[0153] Looking at Table 6a, these results show low viscosity, high softening point, improved flexibility at low temperatures, and an excellent balance between high-temperature and low-temperature properties. The combination of low viscosity and high softening point of the asphalt formulation with the CTTE composition provides a highly desirable balance of processability and strengthening performance.

[0154] Example 7 Application in polymer-modified asphalt (PMA) for road paving and roofing membranes A high Mw counter-tapered thermoplastic elastomer composition was prepared in an 180-liter reactor system operated in batch or semi-batch mode under an inert nitrogen atmosphere according to the teachings of the present invention. CTTE prototype Dyne143A was obtained according to the procedure described in Example 1 and used as an asphalt modifier or asphalt strengthener for polymer-modified asphalt (PMA) formulations for road paving and roofing membranes. The CTTE prototype Dyne143A PMA formulations were prepared and characterized according to the procedures described in Examples 2 and 6.

[0155] The CTTE prototype Dyne143A PMA results are shown in Table 7 below, and based on the total PMA mixture, it is shown that the performance of the novel counter-tapered thermoplastic elastomer composition as an asphalt modifier is high at a CTTE polymer content of 2.3 wt% for road paving and 6 and 12 wt% for roofing membranes. The CTTE prototype Dyne143A PMA processability is compared with the PMA mixtures of two commercially available block copolymers, Solprene® 411 and Solprene® 1205. Solprene® 411 is a multi-arm highly coupled block copolymer (also known as a radial SBn thermoplastic elastomer) having a total styrene content of about 30 wt% as a pure block and no tapered characteristics. Solprene® 1205 is a normal tapered diblock B / S-S copolymer (also known as a gradual SBR) having a total styrene content of about 25 wt% and a block styrene content of about 17.5 wt%.

[0156]

Table 13

[0157] In addition to Table 7, Figures 6 and 7 monitor the entire mixing process at 190 °C and show 20× fluorescence microscope images of CTTE prototype Dyne143A PMA prepared with 2.3 and 6 wt% polymer, respectively. Each arrow points to an image corresponding to the mixing time when complete polymer dispersion was observed in each PMA mixture. The dispersion performance of CTTE prototype Dyne143A in PMA is compared with PMA mixtures of commercially available polymers, Solprene® 411 and Solprene® 1205. Fluorescence microscope images allow the morphology of both the polymer-rich phase and the asphalt-rich phase to be observed. The polymer-rich phase is observed as the brighter region, and the asphalt-rich phase is observed as the darker region. Qualitative comparison of the fluorescence microscope images shown in Figure 6 for the corresponding PMA mixing times of CTTE prototype Dyne143A with Solprene® 411 and Solprene® 1205 reveals that at 2.3 wt%, the polymer-rich phase in CTTE prototype Dyne143A PMA was completely dispersed in 180 minutes. This is very much shorter (by about 25%) than the dispersion time with Solprene® 411 PMA and the same as the dispersion time required with Solprene® 1205 PMA. The reduction in particle size is evidence of enhanced compatibility with asphalt, which is consistent with the findings of L.H. Lewandowski (1994), Rubber Chemistry and Technology, Rubber Reviews, Vol. 67, No. 3, pp. 447-480. Qualitative comparison of the images in Figure 7 corresponding to 6 wt% PMA reveals that the mixing behavior is relatively similar, but the dispersion time is longer. At 6 wt%, the polymer-rich phase in CTTE prototype Dyne143A PMA was completely dispersed in 240 minutes. This is even very much shorter (by about 33%) than the dispersion time with Solprene® 411 PMA and the same as the dispersion time required with Solprene® 1205 PMA. CTTE prototype Dyne143A has a PMA dispersion performance dependence on polymer concentration similar to that of Solprene® 1205.

[0158] Looking at Table 7, these results indicate that at 2.3 wt%, the viscosity of CTTE prototype Dyne143A PMA at 135 °C is low and is intermediate between the viscosity of the higher (by about 30%) Solprene® 411 PMA and the lower (by about 30%) Solprene® 1205 PMA. Surprisingly, even at 12 wt%, the viscosity of CTTE prototype Dyne143A PMA at 160 °C is intermediate between the viscosity of the even higher (by about 70%) Solprene® 411 PMA and the even closer (by about 10%) Solprene® 1205 PMA. CTTE prototype Dyne143A has a PMA viscosity development dependence on polymer concentration similar to that of Solprene® 1205. Also, the low viscosity provides advantages for the mixing and compaction of hot mix asphalt used in road paving.

[0159] Figure 8 shows the maximum performance grade (AASHTO standard PG) temperatures of several polymer modified asphalts (PMA) prepared with 2.3 wt% polymer, monitored over the entire mixing process at various temperatures. The enhanced performance of CTTE prototype Dyne143A PMA mixed at 170, 180, and 190 °C is compared to the commercially available block copolymer Solprene® 411 PMA mixed at 185 °C. Examining Figure 8, these results show that the failure temperature (maximum performance grade temperature) of CTTE prototype Dyne143A PMA is higher than that of Solprene® 411 PMA over the entire mixing process, even when mixed at a 15 °C lower mixing temperature (170 °C). Surprisingly, CTTE prototype Dyne143A PMA provides enhanced performance similar to that of Solprene® 411 PMA, combined with important cost and / or processing advantages.

[0160] In summary, the results described in Example 7 show that the novel counter-tapered thermoplastic elastomer composition has the same dispersion performance dependence on polymer concentration as Solprene® 1205 in the novel polymer-modified asphalt CTTE prototype Dyne143A PMA; the same viscosity development dependence on polymer concentration as Solprene® 1205; and surprisingly, provides reinforcement performance similar to Solprene® 411 PMA, combined with important cost and / or processing advantages. This surprising combination of processability and reinforcement performance of this CTTE prototype Dyne143A PMA provides a highly desirable balance for the asphalt modification industry, for both road paving and roofing membrane applications. In addition to the excellent reinforcement performance of the resulting PMA mixture, the very low viscosity of the asphalt formulation contributes to facilitating the dispersion of the polymer in the asphalt, improving the time required for mixing, improving the pumping capacity, and / or reducing the energy required to do so, and / or promoting the thermal storage stability, thus facilitating the processing, handling, and construction of the modified asphalt mixture even at lower temperatures. This also means significant cost reduction and a more environmentally friendly process.

[0161] Example 8 Application in Polymer-Modified Asphalt (PMA) for Road Paving The high Mw CTTE prototype Dyne143A described in Example 7 was used as an asphalt modifier or asphalt reinforcing agent for polymer-modified asphalt (PMA) for road paving formulations. The CTTE prototype Dyne143A PMA formulations were prepared and characterized according to the procedure described in Example 2.

[0162] The CTTE prototype Dyne143A PMA results are shown in Table 8 below, indicating high performance of a novel counter-tapered thermoplastic elastomer composition as an asphalt modifier for road paving at CTTE polymer contents of 2.3, 2.5, and 2.8 wt% based on the total PMA mixture. The CTTE prototype Dyne143A PMA strengthening performance is compared to the PMA mixtures of two commercially available block copolymers, Solprene® 411 and Solprene® 1205.

[0163]

Table 14

[0164] Looking at Table 8, surprisingly, these results show that at 2.5 wt%, the elastic response at 25 °C of CTTE prototype Dyne143A PMA is high, similar to that of Solprene® 411 PMA at 25 °C, and much higher (by about 35%) than that of Solprene® 1205 PMA at 25 °C. Also surprisingly, at 2.3 and 2.8 wt%, a wide range of performance grades PG are achieved with the CTTE prototype Dyne143A PMA mixture, which is wider than the ranges of Solprene® 411 PMA and Solprene® 1205 PMA. The CTTE prototype Dyne143A provides better PMA strengthening performance and improved high-temperature properties than both Solprene® 411 and Solprene® 1205 for road paving applications. This can be rephrased as having high resistance to plastic deformation, high fatigue resistance, and lower thermal cracking.

[0165] Example 9 Application in polymer-modified asphalt (PMA) for roofing materials and waterproof membranes The high Mw CTTE prototype Dyne143A described in Example 7 was used as an asphalt modifier or asphalt strengthening agent for polymer-modified asphalt (PMA) for roofing materials and waterproofing membrane formulations. The CTTE prototype Dyne143A PMA formulations were prepared and characterized according to the procedures described in Examples 2 and 6.

[0166] The CTTE prototype Dyne143A PMA results are shown in Table 9 below, and at a CTTE polymer content of 6 wt% based on the total PMA mixture loaded with 20 and 30 wt% lime filler content, the performance of the novel counter-tapered thermoplastic elastomer composition as an asphalt modifier for roofing materials and waterproofing membranes is shown to be high. The CTTE prototype Dyne143A PMA processability is compared to the processability of a commercially available block copolymer, Solprene® 411 PMA mixture.

[0167]

Table 15

[0168] Looking at Table 9, these results show that the viscosities of the CTTE prototype Dyne143A PMA loaded with 20 wt% lime filler at 160 and 190 °C are low and much lower (about 35 - 45%) than those of Solprene® 411 PMA loaded with the same filler. Also, the viscosities at 160 and 190 °C similar to those of Solprene® 411 PMA loaded with 20 wt% filler are exhibited by the CTTE prototype Dyne143A PMA loaded with a higher (about 50%) filler loading amount (30 wt% lime filler). The CTTE prototype Dyne143A provides better filled PMA processability than Solprene® 411, thereby enabling PMA formulations with higher filler loading amounts and thus providing important cost savings and higher deformation resistance in applications to roofing materials, roof decks, and waterproofing membranes.

[0169] Example 10 Application in Roofing Materials and Polymer-Modified Asphalt (PMA) for Waterproofing Membranes The high Mw CTTE prototype Dyne143A described in Example 7 was used as an asphalt modifier or asphalt strengthener for polymer-modified asphalt (PMA) for roofing materials and waterproofing membrane formulations. The CTTE prototype Dyne143A PMA formulations were prepared and characterized according to the procedures described in Examples 2 and 6.

[0170] The CTTE prototype Dyne143A PMA results are shown in Table 10 below, and at CTTE polymer contents of 4 and 5 wt% based on the total PMA mixture, the performance of the novel counter-tapered thermoplastic elastomer composition as an asphalt modifier for roofing materials and waterproofing membranes is shown to be high. The CTTE prototype Dyne143A PMA strengthening performance is compared to the strengthening performance of a commercially available block copolymer, the PMA mixture of Solprene® 411.

[0171] [Table 16]

[0172] Referring to Table 10, these results indicate that the balance between the high-temperature performance (softening point) and low-temperature performance (cold bending) of the CTTE prototype Dyne143A PMA has been improved. This is better at low temperatures and acceptable at high temperatures compared to the balance of Solprene® 411 PMA with the same (4 wt%) polymer content. Surprisingly, the excellent balance between the high-temperature performance (softening point) and low-temperature performance (cold bending) of the CTTE prototype Dyne143A PMA is achieved with a polymer content higher than about 20% (5 wt%). This is better at low temperatures and similar at high temperatures compared to the balance of Solprene® 411 PMA prepared with a lower (4 wt%) polymer content. The new high Mw CTTE prototype Dyne143A provides improved PMA reinforcement performance compared to Solprene® 411, enabling good workability at high temperatures and better flexibility (improved fracture resistance) at low temperatures in applications such as roofing materials, roof decks, and waterproof membranes.

[0173] Example 11 Application in Polymer Modified Asphalt (PMA) for Road Paving A low Mw counter-tapered thermoplastic elastomer composition was prepared in a 180-liter reactor system operated in batch / or semi-batch mode under an inert nitrogen atmosphere according to the teachings of the present invention. The low Mw CTTE prototype Dyne143C was obtained according to the procedure described in Example 1 and used as an asphalt modifier or asphalt strengthener for polymer modified asphalt (PMA) for road paving formulations. The CTTE prototype Dyne143C PMA formulations were prepared and characterized according to the procedure described in Example 2.

[0174] The CTTE prototype Dyne143C PMA results are shown in Table 11 below, indicating high performance of the novel counter-tapered thermoplastic elastomer composition as an asphalt modifier for road paving at CTTE polymer contents of 2.3, 2.5, and 2.8 wt% based on the total PMA mixture. The CTTE prototype Dyne143C PMA processing and strengthening performance are compared with the PMA mixtures of two commercially available block copolymers, Solprene® 1205 and Kraton® D1192. The former has already been described in Example 7. The latter has no tapered characteristics and is described as a completely continuous triblock copolymer high vinyl SBS with about 30 wt% total styrene as pure polystyrene blocks.

[0175]

Table 17

[0176] Looking at Table 11, these results show that at 2.3 wt%, the viscosity of the CTTE prototype Dyne143C PMA at 135 °C is very low and surprisingly similar to the viscosities of both the Solprene® 1205 and Kraton® D1192 PMA mixtures. Even more surprisingly, at 2.5 wt%, the elastic response of the CTTE prototype Dyne143C PMA at 25 °C is higher (by about 20 - 40%) than the elastic responses of both the Solprene® 1205 and Kraton® D1192 PMA mixtures. The CTTE prototype Dyne143C is expected to provide a similar PMA viscosity development dependence on polymer concentration as the Solprene® 1205 and Kraton® D1192 PMA mixtures. This is advantageous for the processing and handling of PMA concentrates in the asphalt industry, as well as for the mixing and compaction of hot mix asphalt used in road paving.

[0177] Also, surprisingly, at 2.3 and 2.8 weight percent, a wide range of performance grades PG are achieved with the CTTE prototype Dyne143C PMA blend, which is in the same range as the Solprene® 1205 and Kraton® D1192 PMA blends. The new CTTE prototype Dyne143C provides to the PMA a processability and reinforcement performance balance similar to that of the Solprene® 1205 and Kraton® D1192 PMA blends in road paving applications. This can be rephrased as having high plastic deformation resistance, high fatigue resistance, and lower thermal cracking.

[0178] Example 12 Application in Polymer Modified Asphalt (PMA) for Road Paving The low Mw CTTE prototype Dyne143C described in Example 11 was used as an asphalt modifier or asphalt strengthener for polymer modified asphalt (PMA) for road paving formulations. The CTTE prototype Dyne143C PMA formulations were prepared according to the procedure described in Example 2. Adhesion strength was measured using a TA.XTPlus texture analyzer from Stable Micro Systems under standard temperature and humidity laboratory conditions.

[0179] The CTTE prototype Dyne143C PMA results are shown in Table 12 below, indicating high performance of the novel counter-tapered thermoplastic elastomer composition as an asphalt modifier for road paving at a CTTE polymer content of 2.3 weight percent based on the total PMA blend. The CTTE prototype Dyne143C PMA reinforcement performance is compared to the PMA blends of two commercially available block copolymers, Solprene® 411 and Solprene® 1205.

[0180]

Table 18

[0181] Referring to Table 12, surprisingly, these results show the average adhesion strength of the CTTE prototype Dyne143C PMA, which is very similar to the adhesion strength of Solprene® 1205 PMA and is very high (about 70%) compared to the adhesion strength of Solprene® 411 PMA. The CTTE prototype Dyne143C provides an improvement in adhesion characteristics similar to that of the Solprene® 1205 PMA mixture in terms of PMA strengthening performance. This is an important feature in the interaction between asphalt aggregate surfaces in road paving applications.

[0182] Example 13 Application in Polymer-Modified Asphalt Emulsion (PME) for Road Paving The low Mw CTTE prototype Dyne143C described in Example 11 was used as an asphalt modifier or asphalt strengthener for a polymer-modified asphalt emulsion (PME) for road paving formulations. The CTTE prototype Dyne143C PME formulations were prepared in accordance with the US standard specification RS-1P and characterized according to the procedure described in Example 3. The original CTTE prototype Dyne143C PMA was mixed at 170 °C before the emulsification process.

[0183] The CTTE prototype Dyne143C PME results are shown in Table 13 below, indicating high performance of the novel counter-tapered thermoplastic elastomer composition as an asphalt modifier for road paving emulsions at a CTTE polymer dry base content of 3 wt% based on the total PMA residue and PG64-22 base asphalt fluidized with 5% aromatic solvent. The processability and strengthening performance of the CTTE prototype Dyne143C PME were compared with those of PMEs of two commercially available block copolymers, Solprene® 4318 and Solprene® 1205, and a PME of a commercially available high solids aqueous polymer dispersion, SBR latex Butonal® 4190 with a 24 wt% styrene content.

[0184] [Table 19]

[0185] Referring to Table 13, these results indicate that the polymer-modified asphalt emulsion CTTE prototype Dyne143C PME has low viscosity, excellent storage stability, and excellent sieve residue. Mixing the CTTE prototype Dyne143C PMA at a low temperature (170 °C) before the emulsification process at 150 °C provides an important processing advantage by reducing the required PMA cooling time from about 6 - 8 hours to about 3 - 4 hours. Also, these results indicate that the polymer-modified asphalt residue CTTE prototype Dyne143C PMA has a high elastic response at 10 °C and a better balance between high-temperature properties (softening point) and low-temperature properties (ductility). The CTTE prototype Dyne143C provides improved PME processability and PMA strengthening performance with a better balance of properties, is highly superior to PMEs prepared using commercial polymers, and meets the US standard specification RS-1P for PME road paving applications such as chip seal, tack coat, and cold mixing. The CTTE prototype Dyne143C PMA with improved adhesion strength described in Example 12 is expected to provide the adhesion required for surface treatments such as chip seal applications to polymer-modified asphalt emulsions (PMEs).

[0186] Example 14 Preparation of Counter-Tapered Thermoplastic Elastomer (CTTE) In Example 14, several novel counter-tapered thermoplastic elastomers (CTTE39 to 44) were prepared according to the method claimed in the present invention. Polymers CTTE39 to 44 are counter-tapered diblock A-[A / B] copolymers, and the A-[A / B] diblock consists of a monovinyl aromatic homopolymer block A which is a polystyrene block S and a counter-tapered copolymer block [A / B] which is a styrene / butadiene copolymer block [S / B]. Counter-tapered means that the ratio of B to A in the [A / B] block is lower proximal to the A block compared to the ratio of B to A distal to the A block, and in the counter-tapered diblock A-[A / B] copolymer, the vinyl content is higher proximal to the A block compared to the vinyl content distal to the A block.

[0187] These novel counter-tapered thermoplastic elastomer (CTTE39 - 44) compositions were characterized by GPC, 1H NMR, and DSC methodologies to determine molecular weight averages and molecular weight distribution characteristics such as the peak molecular weight (Mp) and weight average molecular weight (Mw) of the linear diblock; microstructure characteristics such as total styrene, block styrene, and vinyl [A / B] block content; the glass transition temperature (Tg) of the A / B counter-tapered copolymer block; and the melt flow rate (MFI) of the CTTE counter-tapered thermoplastic composition. Further, the calculation of the blockiness of the [A / B] block styrene and [A / B] block was also carried out according to the method used for the characterization of the polymer intermediate block or "B" block in Calc.Mid PSC and Calc.Mid Blocky in U.S. Patent Application Publication No. 2003 / 0176582 of September 18, 2003 by KRATON Polymers U.S. LLC and Bening et al. Tables 14 - 15 show the analytical property results, and Table 16 shows the polymerization conditions of CTTE39 - 44. In the following, the overall procedure similar to that described in Example 1 will be explained. This procedure is used to control the monomer distribution in the anionic copolymerization of 1,3-butadiene (B) and styrene (S) in the presence of ditetrahydrofurylpropane (DTHFP) or tetrahydrofuran (THF) as a polarity regulator and randomizing agent suitable for the styrene / butadiene [S / B] counter-tapered copolymer block. The abbreviations used for the polymerization conditions in Table 16 below are defined as follows: CHx = cyclohexane, STY = styrene, BD = 1,3-butadiene.

[0188] The novel counter-tapered thermoplastic elastomer (CTTE39 - 44) composition of the present invention was prepared in a 5.4 liter reactor system operated in an inert nitrogen atmosphere in batch and / or semi-batch mode according to the teachings of the present invention. Immediately prior to addition to the reactor system, the solvent and monomers were thoroughly purified by passing them through a column set filled with alumina and a molecular sieve so that the water content was reduced to a maximum of 5 ppm. In the first polymerization step, an appropriate amount of purified solvent (CHx) was charged to the reactor and heated to an initial reaction temperature (Ti) of about 50 °C to about 55 °C. Once Ti was reached, an appropriate polarity modifier (randomizing agent) such as ditetrahydrofurylpropane (DTHFP) or tetrahydrofuran (THF) was added to the reactor, followed by the first monovinyl aromatic monomer (first STY) at a ratio of about 10 - 30 wt% of the total monomer mixture. After stabilizing this reaction mixture at Ti, n-butyllithium or other appropriate initiator was added directly to the reactor mixture as an appropriate solvent solution containing an amount of polarity modifier necessary to efficiently initiate the anionic polymerization of the living polystyrene block. The amount of initiator was stoichiometrically calculated as described in the literature to form the individual blocks with the desired molecular weights and to compensate for residual impurities. This first polymerization step was then allowed to proceed adiabatically to complete conversion to form a monovinyl aromatic homopolymer block A with a peak molecular weight Mp in the vicinity of the target value of about 6,000 to about 25,000.

[0189] In the second polymerization step, the addition of both monomers for CTTE 39-44 was started simultaneously, and the addition of the second monovinyl aromatic monomer (second STY) was carried out at a rate of about 7.5 to about 10 wt% of the total monomer mixture at a specified feed rate of about 33 to 46 g / min into the reactor over a predetermined feed time of about 1 minute, and the addition of the conjugated diene monomer (BD) was carried out at a rate of about 60.3 to about 82.5 wt% of the total monomer mixture at a specified feed rate of about 92 to about 127 g / min over a predetermined feed time of about 3 minutes into the reactor slowly. These monomer additions were carried out in a programmed batch and / or semi-batch mode, and the amount of the polarity regulator (randomizing agent) was adjusted to about 0.0069 to about 0.0684 wt% of the total reaction mixture to promote the formation of statistically distributed tapered S / B copolymer blocks in which the composition and vinyl microstructure (1,2-addition) gradually change along the copolymer chain. This second polymerization step was then allowed to proceed adiabatically to complete conversion, raising the final peak temperature (Tp) to about 102.4 to about 116.7 °C, thereby forming a counter-tapered copolymer [A / B] block to obtain a living counter-tapered A-[A / B] diblock copolymer with a peak molecular weight Mp of about 125,000 to about 230,000 as the target value.

[0190] Finally, the living polymer chains were terminated by adding an appropriate alcohol to the final reaction mixture in an amount 10 mol% in excess of the stoichiometric amount. Tables 14 and 15 show the results of the analytical characteristics of the novel counter-tapered thermoplastic elastomer compositions CTTE39 to 44. All molecular weights (Mp and Mw) are shown in units of 1000 (k) and are calculated against standard polystyrene by GPC. The peak molecular weight Mp of the monovinyl aromatic homopolymer block A or polystyrene block of CTTE39 to 44 is from about 6.1 to about 22.1 kg / mol. The peak molecular weight Mp of the A-[A / B] diblock copolymer or S-[S / B] styrene-butadiene diblock copolymer of CTTE39 to 44 is from about 125 to about 230 kg / mol. The weight average molecular weight Mw of CTTE39 to 44 is from about 125 to about 223 kg / mol. The vinyl [A / B] block content of CTTE39 to 44 is from about 34.0 to about 63.0 wt% based on the total butadiene units. The glass transition temperature of the [A / B] counter-tapered copolymer block of CTTE40 to 43 is from about -68.5 to -43.5 °C. The melt flow rate (MFI) of the CTTE42 to 43 compositions is from about 19.5 to about 29.2 g / 10 min. The contents measured by NMR of CTTE39 to 44 are about 18.8 to about 41.8 wt% total styrene based on the total copolymer, about 49.2 to about 83.0 wt% block styrene based on the total styrene units, about 6.7 to about 20.1 wt% [A / B] block styrene based on the [A / B] block copolymer, and about 6.5 to about 27.2 wt% block degree of the [A / B] block based on the [A / B] block styrene units.

[0191]

Table 20

[0192]

Table 21

[0193]

Table 22

[0194] Example 15 Application in polymer-modified asphalt (PMA) for road paving High Mw counter-tapered thermoplastic elastomer A-[A / B] or S-[S / B] diblock compositions having various vinyl [A / B] block (wt%) contents (CTTE D-170A and CTTE D-170B in Table 17) were prepared as described in Example 14 with medium vinyl and high vinyl respectively, and used as asphalt modifiers or asphalt strengtheners for polymer-modified asphalt (PMA) for road paving formulations. All CTTE D-170A and CTTE D-170B PMA formulations were prepared and characterized with the following additional steps according to the procedure described in Example 2: Sulfur was added as a crosslinking agent to CTTE D-170A PMA with a polymer content of 3.0 wt% and CTTE D-170B PMA with a polymer content of 3.0 wt%, and mixed at 2500 RPM, 190 °C + / - 5 °C for about 60 - 120 minutes. CTTE D-170A PMA with a polymer content of 6.0 wt% and CTTE D-170B PMA with a polymer content of 6.0 wt% were mixed at 2500 RPM, 190 °C + / - 5 °C for about 120 - 180 minutes without a crosslinking agent (without sulfur addition). The CTTE D-170A PMA diluent and CTTE D-170B PMA diluent were prepared by diluting the initially prepared mixture with a polymer content of 6.0 wt% with additional pure asphalt, mixing for about 120 - 180 minutes, then adding sulfur as a crosslinking agent and continuing mixing at 2500 RPM, 190 °C + / - 5 °C for about 60 - 120 minutes.

[0195] The results of CTTE polymer-modified asphalt (CTTE D-170A PMA and CTTE D-170B PMA) are shown in Table 17 below. The results show that the performance of the novel counter-tapered thermoplastic elastomer diblock composition is improved when compared to Solprene® 1205, a commercially available low vinyl normally tapered diblock copolymer, as an asphalt modifier for road paving with CTTE polymer contents of 3.0, 3.0 diluted, and 6.0 wt% based on the total PMA mixture.

[0196]

Table 23

[0197] Referring to Table 17, the results of polymer-modified asphalt of CTTE D-170A PMA and CTTE D-170B PMA show higher viscosity, lower penetration, higher softening point, higher elastic recovery, and a wider performance grade (PG) range compared to the results of polymer-modified asphalt of S-1205PMA at the same polymer content and sulfur addition amount. Generally, CTTE D-170A PMA and CTTE D-170B PMA are desirable and predictable polymer-modified asphalts with excellent balance of high-temperature and low-temperature properties, and with high rigidity and high elastic behavior. In particular, for asphalt formulations with low polymer content (i.e., 3 wt%), CTTE D-170A PMA and CTTE D-170B PMA have both high elastic response and high softening point, and exhibit viscosities acceptable for PMA specifications (i.e., kinematic viscosity at 135 °C is about 500 - 3000 mPa·s (cP), and preferably 1000 - 2000 mPa·s (cP) for road paving applications). The CTTE D-170A PMA composition and CTTE D-170B PMA composition provide a desirable balance of processability and enhanced performance, and offer the potential for cost improvement by reducing the polymer content without reducing other properties to a level lower than the performance of S-1205PMA with the same polymer content and sulfur addition. Furthermore, the CTTE D-170A PMA composition and CTTE D-170B PMA composition with 3 wt% polymer content and 2 wt% sulfur addition improve the softening point, elastic recovery, and PG without the high viscosities associated with CTTE D-170A PMA compositions and CTTE D-170B PMA compositions with 6 wt% polymer content without a crosslinking agent (without sulfur addition). Surprisingly, in the dilution process of the CTTE D-170A PMA diluted composition and CTTE D-170B PMA diluted composition from 6 wt% to 3 wt%, when directly compared to the CTTE D-170A PMA composition and CTTE D-170B PMA composition with the same 3 wt% polymer content and 2 wt% sulfur addition, improvements in softening point, elastic recovery, and PG are achieved that exceed a 2 wt% sulfur addition.The enhanced performance improvement of CTTE D-170A PMA composition and CTTE D-170B PMA composition is not only due to high molecular weight, but also due to the characteristics of the counter-tapered thermoplastic elastomer A-[A / B] or S-[S / B] diblock composition (i.e., the block degree of the low [A / B] block and the high vinyl [A / B] block).

[0198] The results of polymer-modified asphalt of CTTE D-170A PMA, CTTE D-170B PMA, CTTE D-170A PMA diluted to a polymer content of 3 wt%, and diluted CTTE D-170B PMA in the presence of a crosslinking agent (i.e., addition of 2.0 wt% sulfur) show a Brookfield viscosity of 1715 - 3350 mPa·s (cP) at 135°C, a penetration of 43 - 46 dmm at 25°C, an R&B softening point of 72 - 88°C, an elastic recovery by torsion of 56 - 62% at 25°C, and an elastic recovery by extensometer of 88 - 90% at 25°C.

[0199] The results of polymer-modified asphalt of CTTE D-170A PMA and CTTE D-170B PMA with a polymer content of 6.0 wt% without a crosslinking agent (i.e., without sulfur addition) show a kinematic viscosity at 135°C of less than 6000 mPa·s (cP), a preferred kinematic viscosity at 135°C of less than 5500 cP, and a most preferred kinematic viscosity at 135°C of less than 5000 mPa·s (cP); a softening point above 70°C, a preferred softening point above 75°C, and a most preferred softening point above 80°C; an elastic recovery by torsion at 25°C above 35%, a preferred elastic recovery by torsion at 25°C above 40%, and a most preferred elastic recovery by torsion at 25°C above 45%; a performance grade wider than 76-10, a preferred performance grade wider than 82-10, and a most preferred performance grade wider than 88-10.

[0200] The results of polymer-modified asphalts of CTTE D-170A PMA and CTTE D-170B PMA with a polymer content of 3.0 wt% and CTTE D-170A PMA and diluted CTTE D-170B PMA diluted to a polymer content of 3.0 wt% in the presence of a crosslinking agent (i.e., addition of 2.0 wt% sulfur) are as follows: kinematic viscosity at 135 °C less than 4000 mPa·s (cP), preferably less than 3500 mPa·s (cP) at 135 °C, and most preferably less than 3000 cP at 135 °C; softening point greater than 60 °C, preferably greater than 65 °C, and most preferably greater than 70 °C; elastic recovery by torsion at 25 °C greater than 45%, preferably greater than 50% for elastic recovery by torsion at 25 °C, and most preferably greater than 55% for elastic recovery by torsion at 25 °C; elastic recovery by extensometer at 25 °C greater than 75%, preferably greater than 80% for elastic recovery by extensometer at 25 °C, and most preferably greater than 85% for elastic recovery by extensometer at 25 °C.

[0201] Example 16 Application in polymer-modified asphalt (PMA) for road paving As described in Example 14, a low Mw counter-tapered thermoplastic elastomer A-[A / B] or S-[S / B] diblock composition (CTTE D-170C in Tables 18 and 19) having a high vinyl [A / B] block (wt%) content was prepared and used as an asphalt modifier or asphalt strengthening agent for polymer-modified asphalt (PMA) for road paving formulations. All CTTE D-170C PMA formulations were prepared and characterized for properties according to the procedure described in Example 2. CTTE D-170C PMA formulations with polymer contents of 3.5, 4.5, and 5.0 wt% without a crosslinking agent (i.e., without adding sulfur) are shown in Table 18. For the CTTE D-170C PMA formulations with polymer contents of 3.5, 4.5, and 5.0 wt% shown in Table 19, sulfur was added as a crosslinking agent and an additional step of mixing at 2500 RPM and 190 °C + / - 5 °C for about 60 - 120 minutes was carried out.

[0202] The results of CTTE polymer modified asphalt (CTTE D-170C PMA) are shown in Tables 18 and 19 below. The results are based on 3.5, 4.5, and 5.0 weight percent CTTE polymer content in the total PMA mixture in the absence (i.e., without sulfur addition) and presence (i.e., 2 weight percent sulfur addition based on the total polymer) of a crosslinking agent, and are compared to Solprene® 1205, a commercially available low vinyl normal tapered diblock copolymer, showing enhanced performance as an asphalt modifier for road paving of a novel counter-tapered thermoplastic elastomer diblock composition.

[0203] [Table 24]

[0204] [Table 25]

[0205] Referring to Table 18, the results of polymer-modified asphalt of CTTE D-170C PMA blends with polymer contents of 3.5, 4.5, and 5.0 wt% without a crosslinking agent (i.e., without adding sulfur) show similar viscosities, low penetration, high softening points, high ductility, high elastic recovery, low phase separation, and a similar performance grade (PG) range compared to the results of polymer-modified asphalt of S-1205PMA with the same polymer content. Overall, CTTE D-170C PMA is a desirable and predictable polymer-modified asphalt with excellent balance of high-temperature and low-temperature properties and high rigidity and high elastic behavior. In particular, for asphalt blends with high polymer contents (i.e., 4.5 and 5.0 wt%), CTTE D-170C PMA has both high elastic response and high softening point, showing a low viscosity (i.e., kinematic viscosity at 135 °C is about 500 - 3000 mPa·s (cP), preferably 1000 - 2000 mPa·s (cP) for road paving applications) desirable for PMA specifications. The CTTE D-170C PMA composition provides a desirable balance of processability and strengthening performance, offers the possibility of cost improvement by reducing the polymer content without reducing other properties to a level below the performance of S-1205PMA with the same polymer content, and offers the possibility of property improvement by applying a longer mixing time at a high temperature to cure the PMA composition in the absence of a crosslinking agent (i.e., without adding sulfur) (especially in the case of high vinyl, counter-tapered diblock compositions).

[0206] The results of polymer-modified asphalt of CTTE D-170C PMA blends with polymer contents of 3.5, 4.5, and 5.0 wt% without a crosslinking agent (i.e., without sulfur addition) show Brookfield viscosities of 823 - 1151 mPa·s (cP) at 135 °C, penetrations of 45 - 52 dmm at 25 °C, R&B softening points of 58 - 69 °C, ductilities of 59 - 110 cm at 25 °C, elastic recoveries by torsion of 33 - 40% at 25 °C, elastic recoveries by extensometer of 54 - 55% at 25 °C, elastic recoveries by extensometer of 25 - 30% at 10 °C, and phase separations of 0.1 - 2.0 °C.

[0207] The results of polymer-modified asphalt of CTTE D-170C PMA blends with polymer contents of 3.5, 4.5, and 5.0 wt% without a crosslinking agent (i.e., without sulfur addition) are as follows: kinematic viscosity at 135°C less than 3000 mPa·s (cP), preferably less than 2000 mPa·s (cP), and most preferably less than 1200 mPa·s (cP); softening point greater than 50°C, preferably 55°C, and most preferably 60°C; elastic recovery at 25°C by extensometer greater than 45%, preferably greater than 50% by extensometer at 25°C, and most preferably greater than 55% by extensometer at 25°C; elastic recovery at 10°C by extensometer greater than 20%, preferably greater than 25% by extensometer at 10°C, and most preferably greater than 30% by extensometer at 10°C; ductility at 25°C greater than 50 cm, preferably greater than 55 cm at 25°C, and most preferably greater than 60 cm at 25°C; phase separation less than 5.0°C, preferably less than 2.0°C, and most preferably less than 1.0°C.

[0208] In Table 19, the results of polymer-modified asphalt of CTTE D-170C PMA blends with polymer contents of 3.5, 4.5, and 5.0 wt% in the presence of a crosslinking agent (i.e., addition of 2 wt% sulfur) show higher viscosity, lower penetration, higher softening point, higher ductility, higher elastic recovery, similar phase separation, and a similar performance grade (PG) range compared to the results of polymer-modified asphalt of S-1205PMA with the same polymer content. Overall, the CTTE D-170C PMA composition formulated in the presence of a crosslinking agent has an excellent balance of high-temperature and low-temperature properties, and is a desirable and predictable polymer-modified asphalt with higher rigidity and more elastic behavior than the CTTE D-170C PMA composition formulated in the absence of a crosslinking agent with the same polymer content. In particular, for asphalt blends with a high polymer content (i.e., 4.5 and 5.0 wt%), CTTE D-170C PMA has both a high elastic response and a high softening point, and exhibits a low viscosity desirable for PMA specifications (i.e., kinematic viscosity at 135 °C is about 500 - 3000 mPa·s (cP), preferably 1000 - 2000 mPa·s (cP) for road paving applications). The CTTE D-170C PMA composition provides a desirable balance of processability and strengthening performance, and offers the potential for cost improvement by reducing the polymer content without reducing other properties to a level below those of S-1205PMA with the same polymer content. Surprisingly, the CTTE D-170C PMA composition formulated without a crosslinking agent shows a more significant improvement in strengthening performance (i.e., higher elastic response and higher softening point) compared to the CTTE D-170C PMA composition formulated in the presence of a crosslinking agent and compared to S-1205PMA with the same polymer content, while maintaining the upper temperature limit of the performance grade PG without reducing processability (i.e., without increasing viscosity). The improvement in the strengthening performance of the CTTE D-170C PMA composition is attributed to the characteristics of the counter-tapered thermoplastic elastomer A-[A / B] or S-[S / B] diblock composition (i.e., low block degree of the [A / B] block and high vinyl [A / B] block).

[0209] The results of the polymer-modified asphalt of CTTE D-170C PMA blends with polymer contents of 3.5, 4.5, and 5.0 wt% in the presence of a crosslinking agent (i.e., addition of 2 wt% sulfur) show a Brookfield viscosity at 135 °C of 968 - 1694 mPa·s (cP), a penetration at 25 °C of 42 - 44 dmm, an R&B softening point of 64 - 83 °C, a ductility at 25 °C of 71 - 91 cm, an elastic recovery at 25 °C by torsion of 55 - 70%, an elastic recovery at 25 °C by extensometer of 74 - 83%, an elastic recovery at 10 °C by extensometer of 46 - 55%, and a phase separation of 0.7 - 1.4 °C.

[0210] The results of the polymer-modified asphalt of CTTE D-170C PMA blends with polymer contents of 3.5, 4.5, and 5.0 wt% in the presence of a crosslinking agent (i.e., addition of 2 wt% sulfur) show a kinematic viscosity at 135 °C of less than 3000 mPa·s (cP), a preferred kinematic viscosity of less than 2500 mPa·s (cP), and a most preferred kinematic viscosity of less than 1750 mPa·s (cP); a softening point of more than 55 °C, a preferred softening point of 60 °C, and a most preferred softening point of 65 °C; an elastic recovery at 25 °C by extensometer of more than 60%, a preferred elastic recovery at 25 °C by extensometer of more than 65%, and a most preferred elastic recovery at 25 °C by extensometer of more than 70%; an elastic recovery at 10 °C by extensometer of more than 35%, a preferred elastic recovery at 10 °C by extensometer of more than 40%, and a most preferred elastic recovery at 10 °C by extensometer of more than 45%; a ductility at 25 °C of more than 60 cm, a preferred ductility at 25 °C of more than 65 cm, and a most preferred ductility at 25 °C of more than 70 cm; and a phase separation of less than 5.0 °C, a preferred phase separation of less than 2.0 °C, and a most preferred phase separation of less than 1.0 °C.

[0211] Example 17 Application in Polymer-Modified Asphalt (PMA) for Roofing Materials and Waterproof Membranes A low Mw counter-tapered thermoplastic elastomer A-[A / B] or S-[S / B] diblock composition (CTTE D-170C in Table 20) having a high vinyl [A / B] block (wt%) content, prepared as described in Example 14, was used as an asphalt modifier or asphalt strengthener in a polymer-modified asphalt (PMA) formulation for roofing and waterproofing membrane applications. The CTTE D-170C PMA formulations were prepared and characterized according to the procedures described in Example 2 and Example 6, respectively. For CTTE D-170C, an additional mixing time of about 60 - 120 minutes was carried out at 2500 RPM, 190 °C + / - 5 °C.

[0212] The results of CTTE D-170C / S-411 (50 / 50) PMA are shown in Table 20 below. The results show that the performance of the novel counter-tapered thermoplastic elastomer diblock composition is improved when compared to Solprene® 1205, a commercially available low vinyl normal tapered diblock copolymer with a polymer content of 8.0 wt% based on the total PMA mixture, as an asphalt modifier for roofing membranes. CTTE D-170C PMA is prepared by mixing two commercially available block copolymers, Solprene® 411 and Solprene® 1205, in a weight ratio of 50 / 50. Solprene® 411 is a multi-arm highly coupled block copolymer (also called a radial SBn thermoplastic elastomer) with a total styrene content of about 30 wt% as a pure block and no tapered characteristics. Solprene® 1205 is a normal tapered diblock B / S-S copolymer (also called a gradual SBR) with a total styrene content of about 25 wt% and a block styrene content of about 17.5 wt%.

[0213]

Table 26

[0214] Referring to Table 20, the results of CTTE D-170C / S-411(50 / 50)PMA show that the viscosity is lower than that of the polymer-modified asphalt of S-411 / S-1205(50 / 50)PMA, the penetration is similar, the softening point is lower, the flexibility at low temperature is similar, and the balance between high-temperature and low-temperature properties is excellent. The CTTE D-170C / S-411(50 / 50)PMA composition exhibits a combination of low viscosity and similar properties at high and low temperatures. The CTTE D-170C / S-411(50 / 50)PMA composition provides a highly desirable balance of processability and strengthening performance. In addition to the excellent strengthening performance of the obtained PMA mixture, the significant reduction in the viscosity of the asphalt blend contributes to the improvement of flow characteristics, facilitates the dispersion of the polymer in the asphalt, shortens the mixing time required even at low temperatures, improves the pumpability, and / or reduces the energy required for application, thereby facilitating the processing, handling, and construction of roof membranes prepared with the modified asphalt mixture. This means significant cost reduction and a more environmentally friendly process.

[0215] The results of CTTE D-170C / S-411(50 / 50)PMA show a Brookfield viscosity of about 809 mPa·s (cP) at 180 °C, a Brookfield viscosity of about 759 mPa·s (cP) at 190 °C, a penetration of about 38 dmm at 25 °C, an R&B softening point temperature of about 106 °C, and a BDA cold bending temperature of about -12 °C.

[0216] Example 18 Application in Polymer-Modified Asphalt (PMA) for Road Paving As described in Example 4, a low Mw counter-tapered thermoplastic elastomer (A-[A / B])2-X or (S-[S / B])2-X linear composition (CTTE D-149C in Table 21) having a high vinyl [A / B] block (wt%) content was prepared by partial coupling and used as an asphalt modifier or asphalt strengthener for polymer-modified asphalt (PMA) for road paving mixtures. The CTTE D-149C PMA mixtures were prepared and characterized with the following additional steps according to the procedure described in Example 2: CTTE D-149C PMA mixtures with polymer contents of 3.0 and 6.0 wt% were prepared without a crosslinking agent (i.e., without sulfur addition). Also, CTTE D-149C PMA diluted to a polymer content of 3.0 wt% was prepared without a crosslinking agent (i.e., without sulfur addition) by diluting the mixture first prepared at a polymer content of 6.0 wt% with additional pure asphalt and continuing mixing at 2500 RPM and 190 °C + / - 5 °C for about 120 - 180 minutes.

[0217] The results of CTTE polymer-modified asphalt (CTTE D-149C PMA) are shown in Table 21 below. The results are based on the total PMA mixture with CTTE polymer contents of 3.0, 3.0 diluted, and 6.0 wt% as asphalt modifiers for road paving, prepared by partial coupling as described in Example 1, and compared with CTTE D-143C of medium vinyl [A / B] block (wt%) content and low Mw counter-tapered thermoplastic elastomer (A-[A / B])n-X or (S-[S / B])n-X radial composition in the form of a novel counter-tapered thermoplastic elastomer linear body with a high vinyl composition, indicating improved performance. CTTE D-143C PMA with polymer contents of 3.0 and 6.0 wt% was prepared and characterized according to the procedure described in Example 2. Also, CTTE D-143C PMA diluted to a polymer content of 3.0 wt% was prepared by diluting the mixture initially prepared at a polymer content of 6.0 wt% with additional pure asphalt and continuing to mix at 2500 RPM and 190 °C + / - 5 °C for about 120 - 180 minutes. To minimize phase separation, a small amount of sulfur (i.e., 0.5 wt% based on the total polymer) was added as a crosslinking agent to CTTE D-143C PMA with polymer contents of 3.0 and 6.0 wt% and CTTE D-143C PMA diluted to a polymer content of 3.0 wt%, and the mixture was further mixed at 2500 RPM and 190 °C + / - 5 °C for 60 - 120 minutes.

[0218]

Table 27

[0219] Referring to Table 21, the results of polymer-modified asphalt of CTTE D-149C PMA show lower viscosity, lower penetration, higher softening point, lower ductility, lower elastic recovery by torsion, higher elastic recovery by extensometer, different phase separation, and different performance grade (PG) ranges, respectively, compared to the results of polymer-modified asphalt of CTTE D-143C PMA with the same polymer content. Generally, CTTE D-149C PMA and CTTE D-143C PMA are desirable and predictable polymer-modified asphalts with excellent balance of high-temperature and low-temperature properties and with high rigidity and high elastic behavior. In all formulations, both CTTE D-149C PMA and CTTE D-143C PMA have both high elastic response (i.e., elastic recovery at 25 °C by extensometer) and high softening point, and according to the PMA standard, CTTE D-149C shows desirable viscosity at polymer contents of 3.0 and 6.0 wt%, and CTTE D-143C PMA shows acceptable viscosity at a polymer content of 3.0 wt% (i.e., kinematic viscosity at 135 °C is about 500 - 3000 mPa·s (cP), preferably 1000 - 2000 mPa·s (cP) for road paving applications). CTTE D-149C PMA and CTTE D-143C PMA compositions provide a desirable balance of processability and enhanced performance. Furthermore, CTTE D-149C PMA compositions formulated at polymer contents of 3.0 and 6.0 wt% without a crosslinking agent (i.e., without sulfur addition) have further improved viscosity, softening point, elastic recovery by extensometer, or PG compared to the corresponding CTTE D-143C PMA compositions, and have less increase in viscosity at polymer contents of 3.0 - 6.0 wt% (i.e., doubled). Surprisingly, in the dilution process of the CTTE D-149C PMA diluted composition from 6 wt% to 3 wt%, when directly compared to the CTTE D-149C PMA composition with the same 3 wt% polymer content, the viscosity, softening point, elastic recovery by extensometer, and PG are similar, the penetration and ductility are lower, and there is little phase separation in the absence of a crosslinking agent (i.e., without sulfur addition).The improvement in the processability and reinforcement performance of CTTE D-149C PMA and CTTE D-143C PMA compositions is due to the characteristics of the counter-tapered thermoplastic elastomer (A-[A / B])2-X or (A-[A / B])n-X partial coupling composition, respectively (i.e., the block degree of the low [A / B] block and the [A / B]n-X intermediate block, and the high vinyl [A / B] block and the [A / B]n-X intermediate block).

[0220] The results of the polymer-modified asphalt of CTTE D-143C PMA with polymer contents of 3.0 and 6.0 wt% in the presence of a crosslinking agent (i.e., a sulfur addition of 0.5 wt%) show Brookfield viscosities at 135 °C of 2970 - 9340 mPa·s (cP), penetration at 25 °C of 45 - 48 dmm, R&B softening points of 58 - 78 °C, ductility at 25 °C of 510 - 150 cm, elastic recovery by torsion at 25 °C of 46 - 74%, elastic recovery by extensometer at 25 °C of 71 - 76%, phase separation of 0.3 - 0.5 °C, and performance grades PG from 70-22 to 76-16.

[0221] The results of the polymer-modified asphalt of CTTE D-149C PMA with polymer contents of 3.0 and 6.0 wt% without a crosslinking agent (i.e., without sulfur addition) show Brookfield viscosities at 135 °C of 915 - 2206 mPa·s (cP), penetration at 25 °C of 33 - 44 dmm, R&B softening points of 60 - 82 °C, ductility at 25 °C of 50 - 145 cm, elastic recovery by torsion at 25 °C of 33 - 52%, elastic recovery by extensometer at 25 °C of 78 - 93%, phase separation of 0.1 - 13 °C, and performance grades PG from 70-16 to 82-16.

[0222] The results of polymer-modified asphalt of CTTE D-149C PMA with polymer contents of 3.0 and 6.0 wt% without a crosslinking agent (i.e., without sulfur addition) show a kinematic viscosity at 135 °C of 500 - 3000 mPa·s (cP), a preferred range of 750 - 2500 mPa·s (cP), and a most preferred range of 915 - 2206 mPa·s (cP); an elastic recovery at 25 °C by extensometer of 50 - 98%, a preferred range of 65 - 95%, and a most preferred range of 78 - 93%; a phase separation range of 0.1 - 13 °C, a preferred range of 0.1 - 1.0 °C, and a most preferred range of 0.1 - 0.2 °C.

[0223] The results of polymer-modified asphalt of CTTE D-149C PMA with a polymer content of 6.0 wt% without a crosslinking agent (i.e., without sulfur addition) show a kinematic viscosity at 135 °C of less than 3000 mPa·s (cP), a preferred kinematic viscosity of less than 2500 mPa·s (cP), and a most preferred kinematic viscosity of 2250 cP mPa·s (cP); an elastic recovery at 25 °C by extensometer of more than 75%, a preferred elastic recovery at 25 °C by extensometer of more than 80%, and a most preferred elastic recovery at 25 °C by extensometer of more than 90%; a phase separation of less than 13 °C, a preferred phase separation of less than 1.0 °C, and a most preferred phase separation of less than 0.2 °C.

[0224] The results of polymer-modified asphalt of CTTE D-149C PMA with a polymer content of 3.0 wt% and CTTE D-149C PMA diluted to a polymer content of 3.0 wt% without a crosslinking agent (i.e., without sulfur addition) show a kinematic viscosity at 135 °C of less than 2000 mPa·s (cP), a preferred kinematic viscosity of less than 1500 mPa·s (cP), and a most preferred kinematic viscosity of less than 1000 mPa·s (cP); an elastic recovery at 25 °C by extensometer of more than 50%, a preferred elastic recovery at 25 °C by extensometer of more than 65%, and a most preferred elastic recovery at 25 °C by extensometer of more than 75%; a phase separation of less than 13 °C, a preferred phase separation of less than 1.0 °C, and a most preferred phase separation of less than 0.2 °C.

[0225] Example 19 Application in adhesives for tapes and labels Performance test procedures for hot melt pressure-sensitive adhesives The TA Instruments ARG2 rheometer was used in parallel plate geometry and in the automatic strain mode to perform dynamic mechanical analysis (DMA) to investigate the rheological properties of a hot melt adhesive (before coating, no backing). The plate diameter was 8 mm and the gap was 2.000 mm. The frequency was 10 rad / s and the heating rate was 3 °C / min. The maximum strain was set at 1.0%. The rheological data was highly reproducible and the uncertainty in the glass transition was about ±0.5 °C. The rheological experiments can predict the relationship between structure and properties and ultimately the performance of the adhesive. These include the temperature of the first tan delta maximum (tanδmax), which is a measure of the Tg of the rubbery matrix. Furthermore, the peak height of the tan delta maximum (tanδmax) indicates how much energy the adhesive can dissipate. The storage modulus G’ at room temperature (25 °C) was also recorded to quantify the compliance of the adhesive at the application temperature. Furthermore, the temperature at which the modulus G’ meets the Dahlquist criterion of 300,000 Pa for quick tack (i.e., Dahlquist temperature T Dahlquist ) was analyzed together with the Dahlquist criterion of 50,000 Pa for measurable holding force. Finally, the third crossover temperature was measured. The third crossover temperature (tanδ = 1) is the temperature near the Tg of the glassy polystyrene domains, at which the storage modulus and the loss modulus become equal (e.g., the same magnitude), and thus the tan delta becomes 1. The third crossover temperature (tanδ = 1) is the temperature at which the adhesive begins to flow and cohesion is lost, and is correlated with the ring-and-ball softening point temperature (RBSPT) and / or the shear adhesion failure temperature (SAFT).

[0226] The processability and strengthening performance of the hot melt adhesive were measured by the following standardized methodology. a) The rolling ball tack test was carried out in accordance with PSTC-6. In this test, a common steel ball with a diameter of 11.1 mm is rolled from an inclined path on the bench top onto a 5 cm × 38 cm (2 inches × 15 inches) strip of tape. The distance the ball moves along the tape is recorded. The shorter the distance the ball rolls on the tape, the stronger the adhesive force of the adhesive. The inclined path was a rolling ball tack tester from Cheminstruments. b) The loop tack test was carried out on a Cheminstruments loop tack tester in accordance with PSTC-16. The crosshead displacement speed was 5 mm / s. In the test, a 2.5 cm × 13 cm (1 inch × 5 inches) tape loop was used. The length of the free loop of the tape not restricted by the grip was 75 mm. The maximum force per unit width of the test piece was recorded. The initial height measured from the bottom of the grip to the substrate surface was 50 mm. The maximum displacement was 44 mm, and the dwell time at the maximum displacement was 1 second. c) The peel energy or peel strength per unit width was determined by a 180° peel test and measured in accordance with PSTC101: Peel Adhesion Test Method A for Pressure Sensitive Tapes - Single-Sided Coated Tapes, Peel Adhesion at 180° Angle. A rectangular strip with dimensions of 2.5 cm × 33 cm (1 inch × 12 inches) was tested using a universal testing machine (UTM) at a crosshead displacement speed of 5.08 mm / s (i.e., 12 inches / min). d) The lap shear strength was measured at 23 °C and -25 °C in accordance with the PSTC method. These tests were carried out to measure the cohesion or shear properties of the adhesive at room temperature and low temperature / freeze temperature after coating two wood test pieces and pressing them together at room temperature with a standard force for a predetermined time. A rectangular test piece with dimensions of 2.5 cm × 7.6 cm (1 inch × 3 inches) was tested using a universal testing machine (UTM) at a crosshead displacement speed of 5.08 mm / s (i.e., 12 inches / min). e) The measurement of the holding force was carried out using a Cheminstruments Bank shear tester in accordance with PSTC-107 method, 180° shear adhesion of pressure sensitive tapes. These tests were carried out to measure the cohesion or shear properties of the adhesive tape at room temperature.Instead of the 25 mm × 25 mm contact area described in PSTC-107, a pressure-sensitive adhesive tape (PSAT) with an area of 13 mm × 13 mm (0.5 inch × 0.5 inch) was used. The PSAT was attached to a stainless-steel coupon using a standard 2 kg roller, and a 1 kg mass was suspended from the tape. The time (in minutes) when the adhesive broke was recorded as the holding force. f) The tensile performance of the hot-melt adhesive was measured in a dog-bone-shaped portion with a thickness of 10 mm (0.394 inch) and a length of 76.2 mm (3.0 inches) (both end tabs of 2.5 cm × 2.5 cm (1 inch × 1 inch) and a central gauge portion of 13 mm × 13 mm (0.5 inch × 0.5 inch)). These were pulled at a speed of 30.5 cm / min (12 inches / min) per minute using an Instron testing machine equipped with pneumatic grips. Next, the tensile stress at the break of the adhesive and the strain at the break were recorded. g) The melt viscosity of the hot-melt adhesive was measured using a Brookfield model RVT Thermosel viscometer with a No. 27 spindle. h) The ring-and-ball softening point temperature was measured using an HRB754 propoint apparatus.

[0227] Hot-melt adhesive for counter-tapered thermoplastic elastomer Several hot melt adhesive formulations containing the counter-tapered thermoplastic elastomer compositions CTTE D-149C HMA and CTTE D-143C HMA of the present invention were prepared according to the following procedure. The counter-tapered thermoplastic elastomer compositions CTTE D-149C and CTTE-D143C described in Example 18 were mixed with the materials in the amounts described in the following formulation. Each counter-tapered thermoplastic elastomer composition CTTE was first placed in a jacketed mixing kettle equipped with a three-blade propeller shear stirrer Eurostar Power Control-Vic IKA, together with a compatibility tackifier resin such as Foral® 85, an oil such as Nyflex® 222, and an antioxidant such as Irganox® 1330, and mixed with the remaining components / additives of the hot melt adhesive formulation. Then, the temperature was raised to a range of about 165 °C to about 177 °C for about 30 minutes or until the mixture melted. After the mixture melted, the temperature was lowered to about 150 °C to 165 °C, and the mixture was first stirred at about 250 rpm. Then, the counter-tapered thermoplastic elastomer composition CTTE was slowly added to the mixture over about 5 to 10 minutes, during which the stirring speed was increased to about 400 rpm and finally to about 750 rpm to promote the incorporation of the polymer into the thickening mixture and avoid the aggregation of un-melted polymer particles. Then, it was mixed at about 750 rpm, and heating at about 170 °C was continued for about 120 minutes or until a smooth and homogeneous mass was observed, thereby obtaining a novel hot melt adhesive composition of the present invention containing the counter-tapered thermoplastic elastomer composition CTTE and the remaining components / additives of the hot melt adhesive formulation. Immediately after the mixing was completed, the novel hot melt adhesive composition was applied to a substrate such as Mylar in a temperature range of about 160 °C to about 170 °C to obtain an adhesive coating layer within the specification range of the test protocol (i.e., coating weight 18 - 22 g / m2).

[0228] The hot melt adhesive formulations of the counter-tapered thermoplastic elastomer compositions CTTE D-149C HMA and CTTE D-143C HMA were composed of the following amounts in parts per hundred parts of rubber (phr): Based on the total amount of the counter-tapered thermoplastic elastomer composition (i.e., CTTE D-149C or CTTE D-143C) in the hot melt adhesive formulation (i.e., 100.00 phr), 178.00 phr of tackifying resin Foral® 85; 50.00 phr of Nyflex® 223 oil; and 4.00 phr of Irganox® 1330 antioxidant.

[0229] The CTTE D-149C HMA-UV formulation for UV curable hot melt pressure sensitive adhesives was composed of the following amounts in parts per hundred parts of rubber (phr): Based on the total amount of the counter-tapered thermoplastic elastomer composition CTTE D-149C in the hot melt adhesive formulation (i.e., 100.00 phr), 178.00 phr of tackifying resin (50:50 weight:weight, Piccolyte A-125:Estergum F-85); 50.00 phr of Nyflex 223 oil; 4.00 phr of Irganox® 1010 antioxidant; and 9.0 phr of photoinitiator (50:50 weight:weight, Omnirad® MBF:Omnirad® 819). UV curing was carried out using a mini-conveyor UV curing unit equipped with a high-intensity mercury lamp with a wavelength of 365 nm and 300 WPI at 10 FPM.

[0230] The performance of the novel hot melt adhesive compositions CTTE D-149C HMA and CTTE D-143C HMA, which contain the counter-tapered thermoplastic elastomer composition of the present invention, was characterized according to the test procedures described in Example 19, as shown in Table 22. The Brookfield melt viscosity of the hot melt adhesives was measured at 130, 150, and 180 °C. CTTE D-149C HMA exhibited Brookfield melt viscosities of 19,260 mPa·s (cP) at 130 °C, 6,694 mPa·s (cP) at 150 °C, and 2,261 mPa·s (cP) at 180 °C. CTTE D-143C HMA exhibited Brookfield melt viscosities of 32,250 mPa·s (cP) at 130 °C, 23,844 mPa·s (cP) at 150 °C, and 15,000 mPa·s (cP) at 180 °C. The novel hot melt adhesives CTTE D-149C HMA and CTTE D-143C HMA exhibit improved processability during application to the substrates for the test procedures. The decrease in Brookfield melt viscosity is not only an important processing performance advantage of the novel hot melt adhesives over the prior art, as it enables higher production rates and cost efficiency under the same processing conditions, but also an advantage in terms of low energy processing performance for a more environmentally friendly process, as it enables lower processing temperatures at the same production rate and cost efficiency.

[0231] Table 22 shows the performance of the novel hot melt adhesive compositions CTTE D-149C HMA and CTTE D-143C HMA. CTTE D-149C HMA shows a ring-and-ball softening point temperature (TRBSP) of about 93°C. CTTE D-143C HMA shows a ring-and-ball softening point temperature (TRBSP) of about 82°C. In the 180° peel test of the hot melt adhesive composition to determine the peel energy or peel force (lbf) per unit width according to the PSTC-101 method, CTTE D-149C HMA shows a peel force of about 2.54 kg (about 5.6 lbf), and CTTE D-143C HMA shows a peel force of about 1.13 kg (about 2.5 lbf). In the loop tack test of the hot melt adhesive composition to determine the maximum force (lbf) per unit width according to the PSTC-16 method, CTTE D-149C HMA shows a loop tack force of about 31700 Pa (about 4.6 lbf / in2), and CTTE D-143C HMA shows a loop tack force of about 30300 Pa (about 4.4 lbf / in2). In the measurement of the holding power of the hot melt adhesive composition to determine the time (minutes) when the adhesive breaks and correlate with the cohesion or shear properties at room temperature, CTTE D-149C HMA shows a holding power time of about 1660 minutes, and CTTE D-143C HMA shows a holding power time of about 1443 minutes. The improvement in the processability and strengthening performance of the CTTE D-149C HMA composition and the CTTE D-143C HMA composition is due to the characteristics of the counter-tapered thermoplastic elastomer (A-[A / B])2-X or the (A-[A / B])n-X partial coupling composition (i.e., the block degree of the low [A / B] block and the [A / B]n-X intermediate block and the high vinyl [A / B] block and the [A / B]n-X intermediate block), respectively.

[0232] The performance of the novel hot melt adhesive composition CTTE D-149C HMA-UV containing the counter-tapered thermoplastic elastomer composition of the present invention was characterized before and after curing according to the test procedures described in Example 19 and is shown in Table 22. The Brookfield melt viscosity of the hot melt adhesive was measured at 150 and 180 °C before curing. CTTE D-149C HMA-UV exhibits Brookfield melt viscosities of 10285 mPa·s (cP) at 150 °C and 2766 mPa·s (cP) at 180 °C. CTTE D-149C HMA-UV before curing exhibits a ring-and-ball softening point temperature (TRBSP) of approximately 110.0 °C. The tensile performance of the hot melt adhesive composition, determined by the universal instrument test method for tensile stress (kgf) and strain (%) at break and correlated with the cohesive or shear properties at room temperature, shows a tensile stress at break of approximately 3.8 kgf and a strain at break of approximately 966% for CTTE D-149C HMA-UV before curing. In the 180° peel test of the hot melt adhesive composition, CTTE D-149C HMA-UV shows a peel force before curing of approximately 1.27 kg (approximately 2.8 lbf) and a peel force after curing of approximately 0.91 kg (approximately 2.0 lbf). In the loop tack test of the hot melt adhesive composition, CTTE D-149C HMA-UV shows a loop tack force before curing of approximately 13800 Pa (approximately 2.0 lbf / in2) and a loop tack force after curing of approximately 68.9 Pa (approximately 0.01 lbf / in2). In the measurement of the holding power of the hot melt adhesive composition, CTTE D-149C HMA-UV shows a holding power time before curing of approximately 27000 minutes and a holding power time after curing of approximately 36400 minutes. The rolling ball tack of the hot melt adhesive composition shows a rolling ball distance before curing of approximately 40.6 mm (approximately 1.6 inches) and a rolling ball distance after curing exceeding 381 mm (15 inches) for CTTE D-149C HMA-UV. Further, as shown in Table 22, the dynamic mechanical analysis (DMA) of CTTE D-149C HMA-UV was performed according to the test procedures and methodology described in Example 19. The first tan delta maximum (tanδmax) temperature, which is a measure of the Tg of the rubbery matrix, increases from a Tg of approximately 15.0 °C before curing to a Tg of approximately 26.8 °C after curing.The third crossover temperature (tanδ = 1) is the temperature at which the adhesive begins to flow and cohesion is lost, and it has a correlation with the Ring and Ball Softening Point Temperature (RBSPT) and / or the Shear Adhesion Failure Temperature (SAFT). The third crossover temperature of the novel hot melt adhesive composition rises from about 113.6 °C before curing to about 120.1 °C after curing.

[0233]

Table 28

[0234] The hot melt adhesive compositions CTTE D-149C HMA and CTTE D-143C HMA have a Brookfield viscosity at 130 °C of 19260 - 32250 mPa·s (cP), a Brookfield viscosity at 150 °C of 6694 - 23844 mPa·s (cP), a Brookfield viscosity at 180 °C of 2261 - 15000 mPa·s (cP), an R&B softening point of 82 - 93 °C, a 180° peel strength of 1.13 - 2.54 kg (2.5 - 5.6 lb f ) and a loop tack of 30300 - 31700 Pa (4.4 - 4.6 lb f / in 2 ) and a holding strength of 1443 - 1660 minutes.

[0235] The hot melt adhesive composition CTTE D-143C HMA has a melt viscosity of less than 45,000 mPa·s (cP) at 130°C, a preferred melt viscosity of less than 40,000 mPa·s (cP) at 130°C, and a most preferred melt viscosity of less than 35,000 mPa·s (cP) at 130°C; a melt viscosity of less than 35,000 mPa·s (cP) at 150°C, a preferred melt viscosity of less than 30,000 mPa·s (cP) at 150°C, and a most preferred melt viscosity of less than 25,000 mPa·s (cP) at 150°C; a melt viscosity of less than 25,000 mPa·s (cP) at 180°C, a preferred melt viscosity of less than 20,000 mPa·s (cP) at 180°C, and a most preferred melt viscosity of less than 15,000 mPa·s (cP) at 180°C; an R&B softening point of over 70°C, a preferred R&B softening point of over 75°C, and a most preferred R&B softening point of over 80°C; a 180° peel strength of over 0.68 kg (1.5 lbf), a preferred 180° peel strength of over 0.91 kg (2.0 lbf), and a most preferred 180° peel strength of over 1.13 kg (2.5 lbf); a loop tack of over 20,700 Pa (3.0 lbf / in2), a preferred loop tack of over 24,100 Pa (3.5 lbf / in2), and a most preferred loop tack of over 27,600 Pa (4.0 lbf / in2); and a holding power of over 500 minutes, a preferred holding power of over 1000 minutes, and a most preferred holding power of over 1400 minutes.

[0236] The hot melt adhesive composition CTTE D-149C HMA has a melt viscosity of less than 30,000 mPa·s (cP) at 130°C, a preferred melt viscosity of less than 25,000 mPa·s (cP) at 130°C, and a most preferred melt viscosity of less than 20,000 mPa·s (cP) at 130°C; a melt viscosity of less than 15,000 mPa·s (cP) at 150°C, a preferred melt viscosity of less than 10,000 mPa·s (cP) at 150°C, and a most preferred melt viscosity of less than 7,000 mPa·s (cP) at 150°C; a melt viscosity of less than 10,000 mPa·s (cP) at 180°C, a preferred melt viscosity of less than 5,000 mPa·s (cP) at 180°C, and a most preferred melt viscosity of less than 2,500 mPa·s (cP) at 180°C; an R&B softening point of over 80°C, a preferred R&B softening point of over 85°C, and a most preferred R&B softening point of over 90°C; a 180° peel strength of over 1.36 kg (3.0 lbf), a preferred 180° peel strength of over 1.81 kg (4.0 lbf), and a most preferred 180° peel strength of over 2.49 kg (5.5 lbf); a loop tack of over 20,700 Pa (3.0 lbf / in2), a preferred loop tack of over 27,600 Pa (4.0 lbf / in2), and a most preferred loop tack of over 31,000 Pa (4.5 lbf / in2); and a holding power of over 500 minutes, a preferred holding power of over 1,000 minutes, and a most preferred holding power of over 1,600 minutes.

[0237] The performance of the novel hot melt adhesive composition CTTE D-149C HMA containing the counter-tapered thermoplastic elastomer composition of the present invention after UV curing shows a decrease in adhesion properties and an increase in cohesive strength (i.e., holding power) and heat resistance (i.e., SAFT).

[0238] Example 20 Application in adhesives for tapes and labels Hot melt adhesive of counter-tapered thermoplastic elastomer Low Mw counter-tapered thermoplastic elastomer A-[A / B] or S-[S / B] diblock compositions with various vinyl [A / B] block (wt%) contents, CTTE D-170C and CTTE D-170D, were prepared as described in Example 14 with high vinyl and medium vinyl, respectively, and used to prepare hot melt adhesive formulations according to the procedure described in Example 19. The counter-tapered thermoplastic elastomer compositions were mixed with the materials in the amounts set forth in the following formulation to obtain the hot melt adhesive compositions of the present invention (CTTE D-170C HMA and CTTE D-170D HMA in Table 23).

[0239] The hot melt adhesive formulations CTTE D-170C HMA and CTTE D-170D HMA were composed of the following amounts in parts per hundred parts of rubber (phr): Based on the total amount of 100.00 phr of polymer in the hot melt adhesive formulation (49.00 phr of CTTE D-170C or CTTE D-170D, and 51.00 phr of SIS), 171.00 phr of tackifying resin (107.00 phr of Escorez® 1310LC and 64.00 phr of Estergum F-85); 50.00 phr of Nyflex 223 oil; and 2.00 phr of Irganox® 1330 antioxidant.

[0240] The performance of the novel hot melt adhesive compositions CTTE D-170C HMA and CTTE D-170D HMA, which contain the counter-tapered thermoplastic elastomer composition of the present invention, was characterized according to the test procedures described in Example 19 as shown in Table 23. The Brookfield melt viscosity of the hot melt adhesives was measured at 150, 160, and 177 °C. CTTE D-170C HMA exhibited Brookfield melt viscosities of 15467 mPa·s (cP) at 150 °C, 9540 mPa·s (cP) at 160 °C, and 5300 mPa·s (cP) at 177 °C. CTTE D-170D HMA exhibited Brookfield melt viscosities of 18292 mPa·s (cP) at 150 °C, 11413 mPa·s (cP) at 160 °C, and 6600 mPa·s (cP) at 177 °C. Solprene® 1205HMA exhibited Brookfield melt viscosities of 14600 mPa·s (cP) at 150 °C, 9730 mPa·s (cP) at 160 °C, and 5700 mPa·s (cP) at 177 °C. The novel hot melt adhesive CTTE D-170C HMA exhibits improved processability during application to the substrates for the test procedures. The decrease in Brookfield melt viscosity is not only an important processing performance advantage of the novel hot melt adhesive over the prior art (i.e., Solprene® 1205HMA) as it allows for a higher production rate and cost efficiency under the same processing conditions, but also has an advantage in low-energy processing performance, which is a more environmentally friendly process as it allows for a lower processing temperature at the same production rate and cost efficiency.

[0241] Table 23 shows the performance of the novel hot melt adhesive compositions CTTE D-170C HMA and CTTE D-170D HMA compared to the conventional hot melt adhesive composition Solprene® 1205HMA. The hot melt adhesive compositions exhibit a ring-and-ball softening point temperature (TRBSP) of approximately 98.4 °C for CTTE D-170C HMA, approximately 96.2 °C for CTTE D-170D HMA, and approximately 96.6 °C for Solprene® 1205HMA. The 180° peel test of the hot melt adhesive compositions to determine the peel energy or peel force (lbf) per unit width according to the PSTC-101 method shows a peel force of approximately 3.36 kg (approximately 7.4 lbf) for CTTE D-170C HMA, approximately 2.72 kg (approximately 6.0 lbf) for CTTE D-170D HMA, and approximately 1.32 kg (approximately 2.9 lbf) for Solprene® 1205HMA. The loop tack test of the hot melt adhesive compositions to determine the maximum force (lbf) per unit width according to the PSTC-16 method shows a loop tack force of approximately 35900 Pa (approximately 5.2 lbf / in2) for CTTE D-170C HMA, approximately 30300 Pa (approximately 4.4 lbf / in2) for CTTE D-170D HMA, and approximately 26200 Pa (approximately 3.8 lbf / in2) for Solprene® 1205HMA. The holding power measurement of the hot melt adhesive compositions to determine the time (minutes) at which the adhesive fails and correlates with the cohesion or shear properties at room temperature shows a holding power time of approximately 157 minutes for CTTE D-170C HMA, approximately 105 minutes for CTTE D-170D HMA, and approximately 25 minutes for Solprene® 1205HMA.Determine the tensile stress (kgf) at break and the strain (%) at break. The tensile performance of the hot melt adhesive composition that correlates with the cohesive or shear properties at room temperature shows a tensile stress at break of about 2.2 kgf and a strain at break of about 2000% for CTTE D-170C HMA, a tensile stress at break of about 1.5 kgf and a strain at break of about 2000% for CTTE D-170D HMA, and a tensile stress at break of about 0.5 kgf and a strain at break of about 2000% for Solprene® 1205HMA. The rolling ball tack test of the hot melt adhesive composition that determines quick tack by measuring the distance the ball moves along the tape according to the PSTC-6 method shows a rolling ball tack distance of about 26.7 mm (about 1.05 inches) for CTTE D-170C HMA, a rolling ball tack distance of about 31.8 mm (about 1.25 inches) for CTTE D-170D HMA, and a rolling ball tack distance of about 12.7 mm (about 0.5 inches) for Solprene® 1205HMA. The processability and strengthening performance of the CTTE D-170C HMA and CTTE D-170D HMA hot melt adhesive compositions are improved compared to conventional compositions due to the characteristics of the counter-tapered thermoplastic elastomer A-[A / B] or S-[S / B] diblock composition (i.e., the block degree of the low [A / B] block and the high / medium vinyl [A / B] block).

[0242] The performance of the novel hot melt adhesive compositions CTTE D-170C HMA and CTTE D-170D HMA, which contain the counter-tapered thermoplastic elastomer block composition of the present invention, was characterized by dynamic mechanical analysis (DMA) conducted according to the test procedures and methodologies described in Example 19, as shown in Table 23. The storage modulus G' of the hot melt adhesive at room temperature (25°C), which quantifies the flexibility of the adhesive at the application temperature following the Dahlquist criterion of 300,000 Pa for measurable quick tack and 50,000 Pa for measurable holding power, is a storage modulus G' of approximately 61,700 Pa at 25°C for CTTE D-170C HMA, a storage modulus G' of approximately 65,500 Pa at 25°C for CTTE D-170D HMA, and a storage modulus G' of approximately 34,600 Pa at 25°C for Solprene® 1205HMA. The maximum peak height of tandelta (tanδmax) of the hot melt adhesive, which indicates how much energy the adhesive can dissipate, is a maximum peak height of tandelta of approximately 2.52 for CTTE D-170C HMA, a maximum peak height of tandelta of approximately 1.92 for CTTE D-170D HMA, and a maximum peak height of tandelta of approximately 1.65 for Solprene® 1205HMA. The first maximum tandelta (tanδmax) temperature, which is a measure of the Tg of the rubbery matrix, is a Tg of approximately 1.5°C for CTTE D-170C HMA, a Tg of approximately 4.4°C for CTTE D-170D HMA, and a Tg of approximately 4.4°C for Solprene® 1205HMA. The third crossover temperature (tanδ = 1), which is the temperature at which the adhesive begins to flow and cohesion is lost, is a crossover temperature of approximately 100.5°C for CTTE D-170C HMA, a crossover temperature of approximately 94.7°C for CTTE D-170D HMA, and a crossover temperature of approximately 94.7°C for Solprene® 1205HMA.

[0243]

Table 29

[0244] The hot melt adhesive compositions CTTE D-170C HMA and CTTE D-170D HMA have a Brookfield viscosity at 150 °C of 15467 to 18292 mPa·s (cP), a Brookfield viscosity at 160 °C of 9540 to 11413 mPa·s (cP), a Brookfield viscosity at 177 °C of 5300 to 6600 mPa·s (cP), an R&B softening point of 96.2 to 98.4 °C, a peel at 180 °C of 2.72 to 3.36 kg (6.0 to 7.4 lb f ), a loop tack of 30300 to 35900 Pa (4.4 to 5.2 lb f / in 2 ), a holding power of 105 to 157 minutes, a tensile stress at break of 1.5 to 2.2 kgf, an elongation at break of about 2000%, a rolling ball tack of 26.7 to 31.8 mm (1.05 to 1.25 inches), a storage modulus G’ at 25 °C of 61700 to 65500 Pa, a tan delta maximum peak height of 1.92 to 2.52, a tan delta maximum temperature (Tg) of 1.5 to 4.4 °C, and a crossover temperature of 94.7 to 100.5 °C.

[0245] The hot melt adhesive compositions CTTE D-170C HMA and CTTE D-170D HMA have a melt viscosity at 150 °C of less than 25,000 mPa·s (cP), a preferred melt viscosity at 150 °C of less than 18,500 mPa·s (cP), and a most preferred melt viscosity at 150 °C of less than 15,500 mPa·s (cP); a melt viscosity at 160 °C of less than 20,000 mPa·s (cP), a preferred melt viscosity at 160 °C of less than 11,500 mPa·s (cP), and a most preferred melt viscosity at 160 °C of less than 9,600 mPa·s (cP); a melt viscosity at 177 °C of less than 15,000 mPa·s (cP), a preferred melt viscosity at 177 °C of less than 7,000 mPa·s (cP), and a most preferred melt viscosity at 177 °C of less than 5,500 mPa·s (cP); an R&B softening point above 85 °C, a preferred R&B softening point above 95 °C, and a most preferred R&B softening point above 98 °C; a 180° peel strength above 1.36 kg (3.0 lbf), a preferred 180° peel strength above 2.27 kg (5.0 lbf), and a most preferred 180° peel strength above 3.18 kg (7.0 lbf); a loop tack above 20,700 Pa (3.0 lbf / in2), a preferred loop tack above 27,600 Pa (4.0 lbf / in2), and a most preferred loop tack above 34,500 Pa (5.0 lbf / in2); a holding power above 25 minutes, a preferred holding power above 100 minutes, and a most preferred holding power above 150 minutes; a tensile stress at break above 0.5 kgf, a preferred tensile stress at break above 1.0 kgf, and a most preferred tensile stress at break above 2.0 kgf; an elongation at break above 500%, a preferred elongation at break above 1,000%, and a most preferred elongation at break above 1,500%; a rolling ball tack less than 76.2 mm (3.0 inches), a preferred rolling ball tack less than 50.8 mm (2.0 inches), and a most preferred rolling ball tack less than 38.1 mm (1.5 inches); a storage modulus G' at 25 °C above 35,000 Pa, a preferred storage modulus G' at 25 °C above 50,000 Pa, and a most preferred storage modulus G' at 25 °C above 60,000 Pa; a tan delta maximum peak height above 1.65, a preferred tan delta maximum peak height above 2.0, and a most preferred tan delta maximum peak height above 2.5Ultra; the maximum temperature difference (Tg) is less than 5°C, preferably less than 4°C, and most preferably less than 3°C; the crossover temperature is more than 90°C, preferably more than 95°C, and most preferably more than 100°C.

[0246] The present invention has been described above, but various changes in techniques, procedures, materials, and devices will be apparent to those skilled in the art. All such modifications within the scope and spirit of the present invention are intended to be included in the appended claims.

Claims

Claim 1 (a) asphalt and / or bitumen, and (b) a first counter-tapered thermoplastic elastomer (first CTTE) composition An asphalt and / or bitumen composition comprising, wherein the asphalt and / or bitumen composition comprises 0.5 to 25 weight percent of the first CTTE composition, and the first CTTE composition comprises Units of at least one monovinyl aromatic monomer A polymerized with units of at least one conjugated diene monomer B so as to form a counter-tapered diblock A-[A / B] copolymer, wherein the A block comprises a polymer of the monovinyl aromatic monomer units, and the [A / B] block is a copolymer of the monovinyl aromatic monomer units and the conjugated diene monomer units, and the [A / B] block is counter-tapered such that the ratio of B to A proximal to the A block is lower than the ratio of B to A distal to the A block, an asphalt and / or bitumen composition. Claim 2 The asphalt and / or bitumen composition according to claim 1, wherein the total amount of the units of the conjugated diene monomer B is more than 55% by weight of the first CTTE composition. Claim 3 The asphalt and / or bitumen composition according to claim 2, wherein the conjugated diene monomer B is at least one monomer selected from the group consisting of 1,3-butadiene, isoprene, myrcene and farnesene. Claim 4 The asphalt and / or bitumen composition according to claim 3, wherein the conjugated diene units are selectively, partially or fully hydrogenated. Claim 5 The asphalt and / or bitumen composition according to claim 1, wherein in the counter-tapered diblock A-[A / B] copolymer, the vinyl content proximal to the A block is higher than the vinyl content distal to the A block. Claim 6 The asphalt and / or bitumen composition according to claim 1, wherein the total amount of the units of the conjugated diene monomer B is more than 55% by weight of the first CTTE composition, and in the counter-tapered diblock A-[A / B] copolymer, the vinyl content proximal to the A block is higher than the vinyl content distal to the A block. Claim 7 The [A / B] block of the first CTTE composition contains 2 to 40% by weight of a monovinyl aromatic monomer A and 60 to 98% by weight of a conjugated diene monomer B, and the asphalt and / or bitumen composition according to claim 1.

8. The asphalt and / or bitumen composition has a kinematic viscosity of 500 to 6000 mPa·s (cP) at 135°C as measured in accordance with ASTM D4402, the asphalt and / or bitumen composition has a softening point above 50°C, and the asphalt and / or bitumen composition has an elastic recovery of more than 45% at 25°C by extensometer, and the asphalt and / or bitumen composition according to claim 1.

9. The asphalt and / or bitumen composition has a kinematic viscosity of 500 to 3000 mPa·s (cP) at 135°C as measured in accordance with ASTM D4402, the asphalt and / or bitumen composition has an elastic recovery of more than 20% at 10°C by extensometer, the asphalt and / or bitumen composition has a ductility of more than 50 cm at 25°C, and the asphalt and / or bitumen composition has a phase separation below 5.0°C, and the asphalt and / or bitumen composition according to claim 8.

10. The asphalt and / or bitumen composition has a kinematic viscosity of less than 4000 mPa·s (cP) at 135°C as measured in accordance with ASTM D4402, the asphalt and / or bitumen composition has a softening point above 55°C, and the asphalt and / or bitumen composition has an elastic recovery of more than 50% at 25°C by extensometer, and the asphalt and / or bitumen composition according to claim 1.

11. The asphalt and / or bitumen composition according to claim 1, further comprising an emulsifier, and the asphalt and / or bitumen composition is emulsified in water to form a PMA residue.

12. The PMA residue has a kinematic viscosity of less than 2000 mPa·s (cP) at 135°C as measured in accordance with ASTM D4402, and the PMA residue has an elastic recovery of more than 20% at 10°C by extensometer, and the asphalt and / or bitumen composition according to claim 11.

13. The asphalt and / or bituminous composition contains 4 to 8% by weight of a first CTTE composition, and the asphalt and / or bituminous composition has a kinematic viscosity of less than 6000 mPa·s (cP) at 135°C, a softening point above 60°C, and an elastic recovery of more than 35% at 25°C by torsion, as measured in accordance with ASTM D4402. The asphalt and / or bituminous composition according to claim 1.

14. The asphalt and / or bituminous composition contains 2 to 4% by weight of a first CTTE composition, and the asphalt and / or bituminous composition has a kinematic viscosity of less than 4000 mPa·s (cP) at 135°C, a softening point above 50°C, an elastic recovery of more than 20% at 25°C by torsion, and an elastic recovery of more than 45% at 25°C by extensometer, as measured in accordance with ASTM D4402. The asphalt and / or bituminous composition according to claim 13.

15. (a) Asphalt and / or bitumen, and (b) A counter-tapered thermoplastic elastomer (CTTE) composition An asphalt and / or bituminous composition comprising, the asphalt and / or bituminous composition contains 0.5 to 25 weight percent of the CTTE composition, and the CTTE composition contains units of at least one monovinyl aromatic monomer A and units of at least one conjugated diene monomer B, and has a linear structure (A - [A / B]) - X - ([B / A] - A) and / or a coupled radial and / or multi-arm structure (A - [A / B])n - X, where X is the residue of either a coupling agent or a multifunctional initiator, and n is an integer from 2 to 30. The CTTE composition has an outer block and / or a terminal block A that is a polymer of monovinyl aromatic monomer units A. The CTTE composition has an intermediate block that is a copolymer of monovinyl aromatic monomer units A and conjugated diene monomer units B, the intermediate block has a central region between the terminal regions, and the B / A ratio is higher in the central region than in the terminal regions. An asphalt and / or bituminous composition.

16. The vinyl content of the terminal regions in the CTTE composition is higher than the vinyl content of the central region. The asphalt and / or bituminous composition according to claim 15.

17. The asphalt and / or bituminous composition contains 0.5 to 25% by weight of the CTTE composition. The asphalt and / or bituminous composition according to claim 15.

18. The asphalt and / or bituminous composition according to claim 15, wherein the asphalt and / or bituminous composition contains 2 to 8% by weight of the CTTE composition.

19. Further comprising a second counter-tapered thermoplastic elastomer (second CTTE) composition, wherein the second CTTE composition contains units of at least one monovinyl aromatic monomer A and units of at least one conjugated diene monomer B, and has a linear structure (A - [A / B]) - X - ([B / A] - A) and / or a coupled radial and / or multi-arm structure (A - [A / B])n - X, where X is a residue of either a coupling agent or a multifunctional initiator, and n is an integer from 2 to 30, the second CTTE composition has an outer block and / or a terminal block A that is a polymer of monovinyl aromatic monomer units A, the second CTTE composition has an intermediate block that is a copolymer of monovinyl aromatic monomer units A and conjugated diene monomer units B, the intermediate block has a central region between the terminal regions, and the B / A ratio is higher in the central region than in the terminal regions, the asphalt and / or bituminous composition according to claim 1.

20. The structure (A - [A / B]) - X - ([B / A] - A) or (A - [A / B])n - X of the second CTTE composition contains a [A / B] - X - [B / A] or [A / B]n - X intermediate block, and the [A / B] - X - [B / A] or [A / B]n - X intermediate block contains 2 to 40% by weight of monovinyl aromatic monomer A and 60 to 98% by weight of conjugated diene monomer B, the asphalt and / or bituminous composition according to claim 19.

21. The asphalt and / or bituminous composition according to claim 20, wherein the conjugated diene monomer B is at least one monomer selected from the group consisting of 1,3-butadiene, isoprene, myrcene, and farnesene.

22. The asphalt and / or bituminous composition according to claim 21, wherein the conjugated diene units are selectively, partially, or completely hydrogenated.

23. The asphalt and / or bituminous composition has a kinematic viscosity of 500 to 3000 mPa·s (cP) at 135°C as measured in accordance with ASTM D4402, and the asphalt and / or bituminous composition has an elastic recovery of more than 75% at 25°C by extensometer. The asphalt and / or bituminous composition according to claim 19.

24. The asphalt and / or bituminous composition has a kinematic viscosity of less than 1000 mPa·s (cP) at 135°C as measured in accordance with ASTM D4402, and the asphalt and / or bituminous composition has an elastic recovery of more than 75% at 25°C by extensometer. The asphalt and / or bituminous composition according to claim 19.

25. The asphalt and / or bituminous composition further contains an emulsifier, and the asphalt and / or bituminous composition is emulsified in water to form a PMA residue. The asphalt and / or bituminous composition according to claim 19.

26. The PMA residue has a kinematic viscosity of less than 600 mPa·s (cP) at 135°C as measured in accordance with ASTM D4402, and the PMA residue has an elastic recovery of more than 75% at 10°C by extensometer. The asphalt and / or bituminous composition according to claim 25.

27. The asphalt and / or bituminous composition contains 4 to 8% by weight of the first and second CTTE compositions, and the asphalt and / or bituminous composition has a kinematic viscosity of less than 3000 mPa·s (cP) at 135°C as measured in accordance with ASTM D4402 and an elastic recovery of more than 90% at 25°C by extensometer. The asphalt and / or bituminous composition according to claim 19.

28. The asphalt and / or bituminous composition contains 2 to 4% by weight of the first and second CTTE compositions, and the asphalt and / or bituminous composition has a kinematic viscosity of less than 1000 mPa·s (cP) at 135°C as measured in accordance with ASTM D4402, an elastic recovery of more than 75% at 25°C by extensometer, and phase separation of less than 0.2°C or less than 0.3%. The asphalt and / or bituminous composition according to claim 27.

29. (a) Asphalt and / or bitumen, and (b) A counter-tapered thermoplastic elastomer (CTTE) composition An asphalt and / or bituminous composition comprising, the asphalt and / or bituminous composition comprises 0.5 to 25 weight percent of the CTTE composition, and the CTTE composition is A counter-tapered diblock A-[A / B] copolymer comprising units of at least one conjugated diene monomer B and units of at least one monovinyl aromatic monomer A, wherein the diblock copolymer has a peak molecular weight of 20,000 to 250,000, wherein the monovinyl aromatic homopolymer block A has a peak molecular weight of at least 5,000, wherein the [A / B] block is counter-tapered, wherein the [A / B] has a vinyl content of at least 15% by weight based on the amount of conjugated diene units in the diblock copolymer, and counter-tapered means that the ratio of B to A in the [A / B] block is lower proximal to the A block than the ratio of B to A distal to the A block, the counter-tapered diblock A-[A / B] copolymer, (2) A block copolymer comprising at least two counter-tapered diblock A-[A / B] copolymers, wherein the block copolymer has at least two of a monovinyl aromatic homopolymer block A and at least one copolymer block of a monovinyl aromatic monomer unit and a conjugated diene monomer unit, wherein the copolymer block is selected from the group consisting of a linear triblock copolymer having a peak molecular weight of at least 1.5 times that of the counter-tapered diblock copolymer, a multi-arm coupling block copolymer having a peak molecular weight of at least 2.5 times that of the counter-tapered diblock copolymer, and mixtures thereof, the block copolymer, an asphalt and / or bitumen composition.

30. The asphalt and / or bitumen composition according to claim 29, wherein the ratio of (1) to (2) in the CTTE composition is from 1:5 to 5:

1.

31. The asphalt and / or bitumen composition according to claim 29, wherein in the diblock copolymer, the vinyl content proximal to the A block is higher than the vinyl content distal to the A block.

32. The asphalt and / or bitumen composition according to claim 29, wherein the amount of the conjugated diene monomer B in the diblock copolymer is more than 55% by weight.

33. The conjugated diene monomer B is at least one monomer selected from the group consisting of 1,3-butadiene, isoprene, myrcene, and farnesene, the asphalt and / or bitumen composition according to claim 32.

34. The conjugated diene units are selectively, partially, or completely hydrogenated, the asphalt and / or bitumen composition according to claim 33.

35. The amount of the monovinyl aromatic monomer unit A in the CTTE composition is 10% to 48% by weight, the asphalt and / or bitumen composition according to claim 32.

36. The vinyl content in the CTTE composition is 15% to 90% by weight based on the total amount of the conjugated diene units B in the CTTE composition, the asphalt and / or bitumen composition according to claim 35.

37. The [A / B] block of the counter-tapered diblock A-[A / B] copolymer contains 2 to 40% by weight of the monovinyl aromatic monomer A and 60 to 98% by weight of the conjugated diene monomer B, the asphalt and / or bitumen composition according to claim 29.

38. The asphalt and / or bitumen composition has a kinematic viscosity of 500 to 3000 mPa·s (cP) at 135°C as measured in accordance with ASTM D4402, and the asphalt and / or bitumen composition has an elastic recovery of more than 75% at 25°C by an extensometer, the asphalt and / or bitumen composition according to claim 29.

39. The asphalt and / or bitumen composition has a kinematic viscosity of less than 1000 mPa·s (cP) at 135°C as measured in accordance with ASTM D4402, and the asphalt and / or bitumen composition has an elastic recovery of more than 75% at 25°C by an extensometer, the asphalt and / or bitumen composition according to claim 29.

40. Further comprising an emulsifier, and the asphalt and / or bitumen composition is emulsified in water to form a PMA residue, the asphalt and / or bitumen composition according to claim 29.

41. The PMA residue has a kinematic viscosity of less than 600 mPa·s (cP) at 135°C as measured in accordance with ASTM D4402, and the PMA residue has an elastic recovery of more than 75% at 10°C by an extensometer, the asphalt and / or bitumen composition according to claim 40.

42. The asphalt and / or bitumen composition contains 4 to 8% by weight of the CTTE composition, and the asphalt and / or bitumen composition has a kinematic viscosity of less than 3000 mPa·s (cP) at 135°C and an elastic recovery of more than 90% at 25°C as measured in accordance with ASTM D4402 using an extensometer. The asphalt and / or bitumen composition according to claim 29.

43. The asphalt and / or bitumen composition contains 2 to 4% by weight of the CTTE composition, and the asphalt and / or bitumen composition has a kinematic viscosity of less than 1000 mPa·s (cP) at 135°C, an elastic recovery of more than 75% at 25°C as measured by an extensometer, and phase separation of less than 0.2°C or less than 0.3% as measured in accordance with ASTM D4402. The asphalt and / or bitumen composition according to claim 42.

44. (a)At least one additive selected from the group consisting of tackifying resins, plasticizers, solvents, coupling agents, crosslinking agents, photoinitiators, and antioxidants, and (b)A first counter-tapered thermoplastic elastomer (first CTTE) composition An adhesive composition comprising, the adhesive composition contains 0.5 to 50% by weight of the first CTTE composition, and the first CTTE composition comprises units of at least one monovinyl aromatic monomer A polymerized with units of at least one conjugated diene monomer B so as to form a counter-tapered diblock A-[A / B] copolymer, the A block contains monovinyl aromatic monomer units, and the [A / B] block is a copolymer of monovinyl aromatic monomer units and conjugated diene monomer units, and the [A / B] block is counter-tapered such that the ratio of B to A proximal to the A block is lower than the ratio of B to A distal to the A block. Adhesive composition.

45. The adhesive composition according to claim 44, wherein the total amount of units of the conjugated diene monomer B is more than 55% by weight of the first CTTE composition.

46. The adhesive composition according to claim 45, wherein the conjugated diene monomer B is at least one monomer selected from the group consisting of 1,3-butadiene, isoprene, myrcene, and farnesene.

47. The adhesive composition according to claim 46, wherein the conjugated diene units are selectively, partially, or completely hydrogenated.

48. The adhesive composition according to claim 44, wherein in the counter-tapered diblock A-[A / B] copolymer, the vinyl content at the proximal end of the A block is higher than the vinyl content at the distal end of the A block.

49. The adhesive composition according to claim 44, wherein the total amount of units of the conjugated diene monomer B is more than 55% by weight of the first CTTE composition, and in the counter-tapered diblock A-[A / B] copolymer, the vinyl content at the proximal end of the A block is higher than the vinyl content at the distal end of the A block.

50. The adhesive composition according to claim 44, wherein the [A / B] block of the first CTTE composition contains 2 to 40% by weight of a monovinyl aromatic monomer A and 60 to 98% by weight of a conjugated diene monomer B.

51. The adhesive composition according to claim 44, wherein the adhesive composition has a melt viscosity of less than 15500 mPa·s (cP) at 150 °C, the adhesive composition has a melt viscosity of less than 9600 mPa·s (cP) at 160 °C, and the adhesive composition has a melt viscosity of less than 5500 mPa·s (cP) at 177 °C.

52. The adhesive composition according to claim 51, wherein the adhesive composition has an R&B softening point temperature of more than 98 °C, a 180° peel strength of more than 3.18 kg (7.0 lbf), a loop tack of more than 34500 Pa (5.0 lbf / in2), a holding power of more than 150 minutes, and a rolling ball tack of less than 38.1 mm (1.5 inches).

53. The adhesive composition according to claim 44, wherein the adhesive composition has a melt viscosity of less than 18500 mPa·s (cP) at 150 °C, the adhesive composition has a melt viscosity of less than 11500 mPa·s (cP) at 160 °C, and the adhesive composition has a melt viscosity of less than 7000 mPa·s (cP) at 177 °C.

54. The adhesive composition according to claim 53, wherein the adhesive composition has an R&B softening point temperature of more than 95 °C, a 180° peel strength of more than 2.27 kg (5.0 lbf), a loop tack of more than 27600 Pa (4.0 lbf / in2), a holding power of more than 100 minutes, and a rolling ball tack of less than 50.8 mm (1.5 inches).

55. (a) at least one additive selected from the group consisting of a tackifying resin, a plasticizer, a solvent, a coupling agent, a crosslinking agent, a photoinitiator, and an antioxidant, and (b) An adhesive composition comprising a counter-tapered thermoplastic elastomer (CTTE) composition, wherein the CTTE composition comprises units of at least one monovinyl aromatic monomer A and units of at least one conjugated diene monomer B, and has a linear structure (A - [A / B]) - X - ([B / A] - A) and / or a coupled radial and / or multi-arm structure (A - [A / B])n - X, where X is a residue of either a coupling agent or a polyfunctional initiator, n is an integer from 2 to 30, the CTTE composition has an outer block and / or a terminal block A that is a polymer of monovinyl aromatic monomer units A, the CTTE composition has an intermediate block that is a copolymer of monovinyl aromatic monomer units A and conjugated diene monomer units B, the intermediate block has a central region between terminal regions, and the B / A ratio is higher in the central region than in the terminal regions, the adhesive composition.

56. The vinyl content in the terminal regions of the CTTE composition is higher than the vinyl content in the central region, the adhesive composition according to claim 55.

57. The adhesive composition comprises 0.5 to 50% by weight of the CTTE composition, the adhesive composition according to claim 55.

58. The adhesive composition comprises 20 to 40% by weight of the CTTE composition, the adhesive composition according to claim 55.

59. Further comprising a second counter-tapered thermoplastic elastomer (second CTTE) composition, the second CTTE composition comprises units of at least one monovinyl aromatic monomer A and units of at least one conjugated diene monomer B, and has a linear structure (A - [A / B]) - X - ([B / A] - A) and / or a coupled radial and / or multi-arm structure (A - [A / B])n - X, where X is a residue of either a coupling agent or a polyfunctional initiator, n is an integer from 2 to 30, the second CTTE composition has an outer block and / or a terminal block A that is a polymer of monovinyl aromatic monomer units A, the second CTTE composition has an intermediate block that is a copolymer of monovinyl aromatic monomer units A and conjugated diene monomer units B, the intermediate block has a central region between terminal regions, and the B / A ratio is higher in the central region than in the terminal regions, the adhesive composition according to claim 44.

60. ​ The structure of the second CTTE composition (A - [A / B]) - X - ([B / A] - A) or (A - [A / B])n - X includes an [A / B] - X - [B / A] or [A / B]n - X intermediate block, and the [A / B] - X - [B / A] or [A / B]n - X intermediate block includes 2 to 40% by weight of a monovinyl aromatic monomer A and 60 to 98% by weight of a conjugated diene monomer B. The adhesive composition according to claim 59.

61. The conjugated diene monomer B is at least one monomer selected from the group consisting of 1,3 - butadiene, isoprene, myrcene, and farnesene. The adhesive composition according to claim 60.

62. The conjugated diene units are selectively, partially, or completely hydrogenated. The adhesive composition according to claim 61.

63. (a) At least one additive selected from the group consisting of tackifying resins, plasticizers, solvents, coupling agents, crosslinking agents, photoinitiators, and antioxidants, and (b) A counter - tapered thermoplastic elastomer (CTTE) composition An adhesive composition comprising, the adhesive composition comprising 0.5 to 50 weight percent of the CTTE composition, and the CTTE composition is (1) A counter - tapered diblock A - [A / B] copolymer comprising units of at least one conjugated diene monomer B and units of at least one monovinyl aromatic monomer A, The diblock copolymer has a peak molecular weight of 20,000 to 250,000, The monovinyl aromatic homopolymer block A has a peak molecular weight of at least 5,000, The [A / B] block is counter - tapered, The [A / B] has a vinyl content of at least 15% by weight based on the amount of conjugated diene units in the diblock copolymer, and Counter - tapered means that the ratio of B to A in the [A / B] block is lower proximal to the A block compared to the ratio of B to A distal to the A block. The counter - tapered diblock A - [A / B] copolymer, and (2) A block copolymer comprising at least two counter - tapered diblock A - [A / B] copolymers, The block copolymer has at least two of a monovinyl aromatic homopolymer block A, and at least one copolymer block of a monovinyl aromatic monomer unit and a conjugated diene monomer unit, The copolymer block is selected from the group consisting of a linear triblock copolymer having a peak molecular weight of at least 1.5 times that of the counter-tapered diblock copolymer, a multi-arm coupling block copolymer having a peak molecular weight of at least 2.5 times that of the counter-tapered diblock copolymer, and mixtures thereof, and the adhesive composition includes the block copolymer.

64. The adhesive composition according to claim 63, wherein the ratio of (1) to (2) in the CTTE composition is from 1:5 to 5:

1.

65. The adhesive composition according to claim 63, wherein in the diblock copolymer, the vinyl content proximal to the A block is higher than the vinyl content distal to the A block.

66. The adhesive composition according to claim 63, wherein the amount of the conjugated diene monomer B in the diblock copolymer is more than 55% by weight.

67. The adhesive composition according to claim 66, wherein the conjugated diene monomer B is at least one monomer selected from the group consisting of 1,3-butadiene, isoprene, myrcene, and farnesene.

68. The adhesive composition according to claim 67, wherein the conjugated diene units are selectively, partially, or completely hydrogenated.

69. The adhesive composition according to claim 66, wherein the amount of the monovinyl aromatic monomer unit A in the CTTE composition is 10% to 48% by weight.

70. The adhesive composition according to claim 69, wherein the vinyl content in the CTTE composition is 15% to 90% by weight based on the total amount of the conjugated diene units B in the CTTE composition.

71. The adhesive composition according to claim 63, wherein the [A / B] block of the counter-tapered diblock A-[A / B] copolymer contains 2 to 40% by weight of the monovinyl aromatic monomer A and 60 to 98% by weight of the conjugated diene monomer B.

72. The adhesive composition according to claim 63, wherein the adhesive composition contains 20 to 40% by weight of the first and second CTTE compositions according to claim 36 or the CTTE composition according to claim 42.

73. The adhesive composition has a melt viscosity of less than 35,000 mPa·s (cP) at 130°C, the adhesive composition has a melt viscosity of less than 25,000 mPa·s (cP) at 150°C, and the adhesive composition has a melt viscosity of less than 15,000 mPa·s (cP) at 180°C. The adhesive composition according to claim 63.

74. The adhesive composition has an R&B softening point temperature of over 70°C, a 180° peel strength of over 0.68 kg (1.5 lbf), a loop tack of over 20,700 Pa (3.0 lbf / in2), and a holding strength of over 500 minutes. The adhesive composition according to claim 73.

75. The adhesive composition has a melt viscosity of less than 20,000 mPa·s (cP) at 130°C, the adhesive composition has a melt viscosity of less than 7,000 mPa·s (cP) at 150°C, and the adhesive composition has a melt viscosity of less than 2,500 mPa·s (cP) at 180°C. The adhesive composition according to claim 63.

76. The adhesive composition has an R&B softening point temperature of over 90°C. The adhesive composition according to claim 75.

77. The adhesive composition has an R&B softening point temperature of over 80°C, a 180° peel strength of over 1.36 kg (3.0 lbf), a loop tack of over 20,700 Pa (3.0 lbf / in2), and a holding strength of over 500 minutes. The adhesive composition according to claim 75.

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