Propylene-ethylene copolymers and adhesives containing propylene-ethylene copolymers

Abstract

Due to the specific propylene and ethylene content, triad tacticity, viscosity, and crystallinity, propylene-ethylene copolymers are provided that exhibit excellent tensile strength and mechanical properties. Furthermore, the inventors have discovered that specific processing conditions, such as polymerization temperature and external donor-to-catalyst ratio, can facilitate the production of the high tensile strength propylene-ethylene copolymers described herein. Furthermore, the high tensile strength propylene-ethylene copolymers may be used to produce various hot melt adhesives, such as those for sanitary, woodworking, laminating, and packaging applications, that exhibit unique and excellent mechanical properties.

Description

[Technical Field]

[0001] (CROSS-REFERENCE TO RELATED APPLICATIONS) This patent application claims the benefit of priority to prior U.S. patent application Ser. No. 17 / 873,893, filed July 26, 2022, entitled "PROPYLENE-ETHYLENE COPOLYMERS AND ADHESIVES CONTAINING PROPYLENE-ETHYLENE COPOLYMERS." The entirety of the above-identified prior U.S. patent application is incorporated by reference into this patent application.

[0002] FIELD OF THE INVENTION The present invention relates generally to propylene-ethylene copolymers and adhesives containing such copolymers. In particular, although not exclusively, the present invention relates generally to propylene-ethylene copolymers that exhibit excellent tensile properties and adhesives containing such copolymers. [Background technology]

[0003] Generally, hot melt adhesives contain two or more polyolefin polymers because most polyolefin polymers exhibit one or more properties, such as low viscosity and / or low cohesive strength, that make them unsuitable for use alone in forming adhesives. Therefore, most hot melt adhesives require a blend of a low viscosity polyolefin polymer and a high viscosity polyolefin polymer to meet the specific performance criteria for the intended application of the adhesive and to meet the viscosity window for adhesive sprayability.

[0004] Due to the shortcomings of existing polyolefin polymers, some manufacturers have tried to modify the propylene content and ethylene content of polyolefin polymers, thereby forming polymers with a specific ratio of needle penetration to softening point.However, despite the improvements associated with such polymers, these polymers generally do not exhibit the necessary tensile strength and mechanical properties that can be utilized by themselves when forming adhesive compositions without the need for secondary polymers.These secondary polymers that contain higher tensile and mechanical properties also typically have higher Ring and Ball softening temperatures and higher viscosities, which makes the adhesive melt slower, more energy-intensive, and more difficult to process.In addition, when higher tensile polyolefin polymers are used, the high initial adhesive strength generally decreases unacceptably with age, especially in hygiene applications such as diaper adhesives.

[0005] Thus, there remains a need for polyolefin polymers that exhibit desirable tensile strength and manageable processing properties for use in adhesive compositions. Additionally, there is a need for polyolefin polymers that have desirable tensile strength and adhesive strength that do not decrease unacceptably with aging. Summary of the Invention

[0006] One or more embodiments of the present disclosure generally relate to a propylene-ethylene copolymer comprising propylene and ethylene, wherein the propylene-ethylene copolymer (a) comprises 77 to 90 weight percent propylene, (b) comprises 52% to 75% triad tacticity (mm%), (c) has a Brookfield viscosity at 190°C of at least 4,000 cP, (d) exhibits a Ring and Ball softening point of 90 to 135°C, and (e) exhibits a tensile strength at break of at least 2.5 MPa.

[0007] With respect to the propylene-ethylene copolymer disclosed above, one or more embodiments of the present disclosure generally relate to adhesives comprising the above-referenced propylene-ethylene copolymer. As described above, the propylene-ethylene copolymer (a) comprises 77 to 90 weight percent propylene, (b) comprises 52% to 75% triad tacticity (mm%), (c) has a Brookfield viscosity of at least 4,000 cP at 190°C, (d) exhibits a Ring and Ball softening point of 90 to 135°C, and (e) exhibits a tensile strength at break of at least 2.5 MPa. Further, the adhesive comprises (a) 5 to 100 weight percent propylene-ethylene copolymer, (b) 0 to 55 weight percent of at least one second polymer, (c) up to 70 weight percent of at least one tackifier, (d) up to 20 weight percent of processing oil, and (e) up to 35 weight percent of at least one wax.

[0008] The following statements refer to various aspects of the present disclosure. The following statements regarding aspects may be combined in any combination or may be applicable separately to the relevant aspects (e.g., one of the following limitations may be applicable to a first aspect, but another limitation may not be applicable to the first aspect).

[0009] According to a first aspect of the present disclosure, there is provided a propylene-ethylene copolymer comprising propylene and ethylene, the propylene-ethylene copolymer comprising: (a) 77 to 90 weight percent propylene; (b) containing 52% to 75% triad tacticity (mm%); (c) having a Brookfield viscosity of at least 4,000 cP at 190°C; (d) exhibiting a ring and ball softening point of 90 to 155°C; and (e) exhibit a tensile strength at break of at least 2.5 MPa;

[0010] In accordance with the first embodiment, the propylene-ethylene copolymer may comprise 10 to 23 weight percent ethylene.

[0011] Additionally or alternatively, the propylene-ethylene copolymer has a triad tacticity of 53% to 70%.

[0012] Additionally or alternatively, the propylene-ethylene copolymer has a Brookfield viscosity at 190°C of 4,000 to 88,000 cP.

[0013] Additionally or alternatively, the propylene-ethylene copolymer exhibits a heat of crystallization of 15 to 42 J / g and a heat of fusion of 9 to 33 J / g.

[0014] Additionally or alternatively, the propylene-ethylene copolymer exhibits a ring and ball softening point of 100 to 135° C. and a needle penetration of 2 to 24 dmm.

[0015] Additionally or alternatively, the propylene-ethylene copolymer exhibits an elongation at break of from 100% to 1,000% and a tensile strength at break of from 2.5 to 20 MPa.

[0016] Additionally or alternatively, the propylene-ethylene copolymer comprises less than 1 weight percent C4-C6 10 It may also contain an alpha-olefin.

[0017] According to a second aspect of the present disclosure, alone or in combination with the first aspect, the propylene-ethylene copolymer comprises: (i) containing 10 to 23 weight percent ethylene; (ii) having a triad tacticity (mm%) of 53% to 70%; (iii) having a Brookfield viscosity of 4,000 to 88,000 cP at 190°C; (iv) exhibiting a tensile strength at break of 2.5 to 20 MPa; and (v) It exhibits a penetration of 3 to 23 dmm.

[0018] According to a third aspect of the present disclosure, alone or in combination with the first and second aspects, the propylene-ethylene copolymer comprises: (a) 77 to 90 weight percent propylene; (b) having a triad tacticity (mm%) of 52% to 75%; (c) having a ring and ball softening point of 95°C to 125°C; (d) a Brookfield viscosity of 2,000 to 7,000 cP at 190°C; and (e) (i) a tensile strength at break of at least 4 MPa; or (ii) exhibit a tensile strength at break of at least 4 MPa and an elongation at break of at least 100%;

[0019] According to a fourth aspect of the present disclosure, there is provided a propylene-ethylene copolymer comprising propylene and ethylene, the propylene-ethylene copolymer comprising: (a) 77 to 90 weight percent propylene; (b) containing 52% to 75% triad tacticity (mm%); (c) having a Brookfield viscosity of 7,000 to 15,000 cP at 190°C; (d) exhibiting a ring and ball softening point of 90 to 135°C; and (e) exhibit a tensile strength at break of at least 2 MPa.

[0020] According to a fifth aspect of the present disclosure, there is provided a propylene-ethylene copolymer comprising propylene and ethylene, the propylene-ethylene copolymer comprising: (a) containing 77 to less than 89 weight percent propylene; (b) containing 52% to 75% triad tacticity (mm%); (c) having a Brookfield viscosity of greater than 15,000 cP and less than 88,000 cP at 190°C; (d) exhibiting a ring and ball softening point of 100°C to 155°C; and (e) exhibit a tensile strength at break of at least 2.5 MPa;

[0021] According to a sixth aspect of the present disclosure, there is provided a composition comprising a propylene-ethylene copolymer as discussed in the first to fifth aspects, as well as additions and alternatives related to those aspects.

[0022] According to a seventh aspect of the present disclosure, there is provided a process for producing the propylene-ethylene copolymers of the first to fifth aspects, and in addition or alternative to those aspects, comprising polymerizing ethylene and propylene at a temperature of 160° C. or less, wherein the polymerization is carried out in the presence of a catalyst system having a molar ratio of aluminum to titanium in the range of 1:1 to 100:1.

[0023] According to an eighth aspect of the present disclosure, (a) 5 to 100 weight percent of a propylene-ethylene copolymer; (i) 77 to 90 weight percent propylene; (ii) containing 52% to 75% triad tacticity (mm%); (iii) having a Brookfield viscosity of at least 4,000 cP at 190°C; (iv) exhibiting a ring and ball softening point of 90 to 135°C; and (v) a propylene-ethylene copolymer exhibiting a tensile strength at break of at least 2.5 MPa; (b) 0 to 55 weight percent of at least one second polymer; (c) 70 weight percent or less of at least one tackifier; (d) 20 weight percent or less of a processing oil; (e) 35 weight percent or less of at least one wax.

[0024] In relation to the eighth embodiment, the propylene-ethylene copolymer may contain 10 to 23 weight percent ethylene.

[0025] Additionally or alternatively, the propylene-ethylene copolymer has a triad tacticity of 53% to 70%.

[0026] Additionally or alternatively, the propylene-ethylene copolymer has a Brookfield viscosity at 190°C of 4,000 to 88,000 cP.

[0027] Additionally or alternatively, the propylene-ethylene copolymer exhibits a heat of crystallization of 15 to 42 J / g and a heat of fusion of 9 to 33 J / g.

[0028] Additionally or alternatively, the propylene-ethylene copolymer exhibits a ring and ball softening point of 100 to 135° C. and a needle penetration of 2 to 24 dmm.

[0029] Additionally or alternatively, the propylene-ethylene copolymer exhibits an elongation at break of from 100% to 1,000% and a tensile strength at break of from 2.5 to 20 MPa.

[0030] Additionally or alternatively, the composition comprises 20 to 80 weight percent propylene-ethylene copolymer.

[0031] Additionally or alternatively, the composition comprises: (a) 25 to 45 weight percent of a propylene-ethylene copolymer; (b) 0 to 15 weight percent of a second polymer; (c) 45 to 50 weight percent of a tackifier; (d) 0 to 15 weight percent processing oil; (e) 0 to 10 weight percent wax.

[0032] Additionally or alternatively, the composition has a Brookfield viscosity at 190°C in the range of 500 to 20,000 cP.

[0033] According to a ninth aspect of the present disclosure, (a) 5 to 100 weight percent of a propylene-ethylene copolymer; (i) 77 to 90 weight percent propylene; (ii) containing 52% to 75% triad tacticity (mm%); (iii) exhibiting a ring and ball softening point of 90°C to 135°C; (iii) a Brookfield viscosity of 7,000 to 15,000 cP at 190°C; and (iv) a propylene-ethylene copolymer exhibiting a tensile strength at break of at least 2 MPa; (b) 0 to 55 weight percent of at least one second polymer; (c) 70 weight percent or less of at least one tackifier; (d) 20 weight percent or less of a processing oil; (e) 35 weight percent or less of at least one wax.

[0034] In relation to a ninth aspect, the composition comprises: (a) 35 to 50 weight percent of a propylene-ethylene copolymer; (b) 0 to 15 weight percent of a second polymer; (c) 35 to 50 weight percent of a tackifier; (d) 0 to 15 weight percent processing oil; (e) 0 to 10 weight percent wax.

[0035] Additionally or alternatively, the composition comprises: (a) 35 to 55 weight percent of a propylene-ethylene copolymer; (b) 35 to 55 weight percent of a tackifier; (c) 0 to 15 weight percent processing oil; (d) 0 to 7 weight percent wax.

[0036] Additionally or alternatively, the composition has a Brookfield viscosity at 150°C in the range of 1,000 to 4,000 cP.

[0037] Additionally or alternatively, the composition exhibits a peel strength after 24 hours aging that is at least 80 percent of the initial peel strength of the composition.

[0038] According to a tenth aspect of the present disclosure, (a) 30 to 45 weight percent of a propylene-ethylene copolymer, (i) 77 to 90 weight percent propylene; (ii) containing 52% to 75% triad tacticity (mm%); (iii) exhibiting a ring and ball softening point of 90°C to 135°C; (iii) a Brookfield viscosity of 7,000 to 15,000 cP at 190°C; and (iv) a propylene-ethylene copolymer exhibiting a tensile strength at break of at least 2 MPa; (b) 0 to 15 weight percent of a second polymer; (c) 40 to 50 weight percent of a tackifier; (d) 0 to 20 weight percent processing oil; (e) 0 to 10 weight percent of a wax.

[0039] In accordance with a tenth embodiment, the composition has a Brookfield viscosity at 150°C in the range of 1,000 to 5,000 cP.

[0040] Additionally or alternatively, the composition exhibits a peel strength after 24 hours aging that is at least 80 percent of the initial peel strength of the composition.

[0041] According to an eleventh aspect of the present disclosure, (a) 5 to 100 weight percent of a propylene-ethylene copolymer; (i) contains at least 77 weight percent and less than 89 weight percent propylene; (ii) containing 52% to 75% triad tacticity (mm%); (iii) exhibiting a ring and ball softening point of 100°C to 155°C; (iii) has a Brookfield viscosity of greater than 15,000 cP and less than 88,000 cP at 190°C; and (iv) a propylene-ethylene copolymer exhibiting a tensile strength at break of at least 2.5 MPa; (b) 0 to 55 weight percent of at least one second polymer; (c) 70 weight percent or less of at least one tackifier; (d) 20 weight percent or less of a processing oil; (e) 35 weight percent or less of at least one wax.

[0042] In relation to an eleventh aspect, the composition comprises: (a) 30 to 45 weight percent of a propylene-ethylene copolymer; (b) 0 to 15 weight percent of a second polymer; (c) 40 to 50 weight percent of a tackifier; (d) 10 to 20 weight percent processing oil; (e) 0 to 10 weight percent wax.

[0043] In accordance with an eleventh embodiment, the composition has a Brookfield viscosity at 150°C in the range of 1,000 to 5,000 cP.

[0044] Additionally or alternatively, the composition has a Brookfield viscosity at 190°C in the range of 1,000 to 20,000 cP.

[0045] Additionally or alternatively, the composition exhibits a peel strength after 24 hours aging that is at least 80 percent of the initial peel strength of the composition.

[0046] According to a twelfth aspect of the present disclosure, there is provided an article comprising the propylene-ethylene copolymer of the first to fifth aspects and / or the composition of the sixth and / or eighth to eleventh aspects, wherein the article is an adhesive, sealant, caulking compound, roofing membrane, waterproofing membrane and underlayment, carpet, laminate, laminate article, tape, label, mastic, polymer blend, wire coating, molded article, heat seal coating, disposable hygiene article, insulated glass (IG) unit, bridge deck, electronic enclosure, waterproofing membrane, waterproofing compound, underlayment, cable flooding / filling compound, sheet molding compound, dough molding compound, overmolding compound, rubber compound, polyester composite, glass composite, glass fiber reinforced plastic, wood plastic composite, polyacrylic blend compound, lost wax precision casting, investment casting wax composition, bookbinding, candle, window, tire, film, gasket, seal and when the article is an adhesive, the adhesive comprises a packaging adhesive, a food contact grade adhesive, an indirect food contact packaging adhesive, a product assembly adhesive, a woodworking adhesive, an edge banding adhesive, a profile wrapping adhesive, a flooring adhesive, an automotive assembly adhesive, a structural adhesive, a flexible laminating adhesive, a rigid laminating adhesive, a flexible film adhesive, a flexible packaging adhesive, a home repair adhesive, an industrial adhesive, a construction adhesive, a furniture adhesive, a mattress adhesive, a pressure sensitive adhesive (PSA), a PSA tape, a PSA label, a PSA protective film, a cling film, a laminating adhesive, a flexible packaging adhesive, a heat seal adhesive, an industrial adhesive, a sanitary nonwoven construction adhesive, a sanitary core integrity adhesive, or a sanitary elastic attachment adhesive. [Brief explanation of the drawings]

[0047] Embodiments of the present invention are described herein with reference to the following drawings. [Figure 1] 1 is a graph comparing the propylene content and tensile strength of the copolymers in Example 1. [Figure 2]1 is a graph comparing the propylene content and tensile strength of the copolymers in Example 2. [Figure 3] 1 is a graph comparing the propylene content and tensile strength of the copolymers in Example 3. [Figure 4] 1 is a graph comparing the viscosity and tensile strength of copolymers from Examples 1-3. [Figure 5] 1 shows peel strength values for Catbridge trials for Example 6. [Figure 6] 1 shows peel strength values for Catbridge trials for Example 7. [Figure 7] 1 shows peel strength values for Catbridge trials for Example 8. DETAILED DESCRIPTION OF THE INVENTION

[0048] The inventors have discovered that propylene-ethylene copolymers having specific propylene and ethylene contents and triad tacticities, in combination with other characteristics such as viscosity and crystallinity, can exhibit excellent tensile strength and mechanical properties. Furthermore, the inventors have discovered that specific processing conditions, such as polymerization temperature and external donor-to-catalyst ratio, can facilitate the production of the inventive propylene-ethylene copolymers described herein. Furthermore, the inventors have discovered that these excellent tensile strength propylene-ethylene copolymers can be used to produce a variety of compositions, including adhesives for sanitary, woodworking, laminating, and packaging applications, that exhibit unique and excellent mechanical properties (e.g., excellent peel strength and aged peel strength).

[0049] The viscosity of a polymer is determined by the molecular weight of the entangled polymer melt raised to the power 3.4 (M 3.4) is known to be proportional to the molecular weight. It is also known that the mechanical strength of a polymer increases with molecular weight as long polymer chains become entangled, increasing the strength of the bulk polymer. As a result, polymers of similar monomer composition and viscosity (molecular weight) have similar tensile strength. The inventors have discovered that the tensile strength and elongation at break of the propylene-ethylene copolymers of the present invention are unexpectedly high at a given propylene content and viscosity.

[0050] More specifically, the inventors have discovered that the triad tacticity of propylene-ethylene copolymers can be important for controlling tensile strength, elongation at break, crystallinity, penetration, and adhesive aging properties. Furthermore, the inventors have discovered that because crystalline defects caused by ethylene content also affect these important physical properties, the triad tacticity must be selectively controlled along with the ethylene content of the copolymers of the present invention. Furthermore, as described in more detail below, the inventors have discovered that the polymerization temperature and external donor-to-catalyst ratio can be effective ways to control the triad tacticity of the resulting propylene-ethylene copolymers.

[0051] Furthermore, the inventors have discovered that the propylene-ethylene copolymers of the present invention can be used as the sole polymer or as the primary polymer in producing desired adhesives. The inventors have discovered that adhesive formulations containing the propylene-ethylene copolymers of the present invention can exhibit desirable softening points and viscosities that allow the adhesives to be sprayed at 150°C. Furthermore, such adhesives can exhibit stable or increased peel strength after aging for 24 hours, 4 hours (38°C), 2 weeks (55°C), and 1 month (25°C).

[0052] Important features of the propylene-ethylene copolymers of the present invention are described in more detail below: While most of the following features and properties of the propylene-ethylene copolymers and adhesives of the present invention may be listed separately, it is noted that it is contemplated that each of the following features and / or properties of the copolymers and adhesives are not mutually exclusive and may be combined and present in any combination, provided such combinations of features are not contradictory (e.g., incompatible weight percent ranges).

[0053] According to various embodiments, the propylene-ethylene copolymers described herein can contain various amounts of ethylene. In some embodiments, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer can contain at least 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18 weight percent ethylene, based on the total weight of the copolymer. Additionally or alternatively, the propylene-ethylene copolymer can contain less than 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, or 18 weight percent ethylene, based on the total weight of the copolymer.

[0054] In some embodiments, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer can comprise in the range of 0.5 to 30, 0.5 to 25, 0.5 to 23, 0.5 to 21, 0.5 to 18, 5 to 30, 5 to 25, 5 to 23, 5 to 21, 5 to 18, 8 to 30, 8 to 25, 8 to 23, 8 to 21, 8 to 18, 10 to 30, 10 to 25, 10 to 23, 10 to 21, 10 to 18, 15 to 30, 15 to 25, 15 to 23, 15 to 21, 15 to 18, 18 to 30, 18 to 25, 18 to 23, or 18 to 21 weight percent ethylene, based on the total weight of the copolymer.

[0055] Further, in various embodiments, the propylene-ethylene copolymer can contain various amounts of propylene. In some embodiments, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer can include at least 72, 75, 77, 78, 79, 80, 81, or 82 weight percent propylene, based on the total weight of the copolymer. Additionally or alternatively, the propylene-ethylene copolymer can include less than 90, 89, 88, 87, 86, 85, 84, 83, or 82 weight percent propylene, based on the total weight of the copolymer.

[0056] In some embodiments, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer can comprise in the range of 72 to 90, 72 to 89, 72 to 88, 77 to 90, 77 to 89, 77 to 88, 77 to 86, 77 to 84, 77 to 82, 79 to 90, 79 to 89, 79 to 88, 79 to 86, 79 to 84, 79 to 82, 82 to 90, 82 to 89, or 82 to 88 weight percent propylene, based on the total weight of the copolymer.

[0057] The ethylene and propylene content of the copolymers is determined by NMR via the technique described by Wang et al. in Macromolecules 2000, 33, 1157-1162, which is incorporated herein by reference in its entirety.

[0058] In one embodiment, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer may comprise one or more C4-C 10 It may contain alpha-olefins, generally C4 to C 10 Alpha-olefins can be used to increase the resulting bond strength of the copolymer when utilized in adhesives. These C4-C 10 Alpha-olefins can include, for example, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, and combinations thereof.

[0059] In some embodiments, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer has no more than 10, 8, 5, 3, 2, 1, 0.5, or 0.1 weight percent of at least one C4-C6 olefin, based on the total weight of the copolymer. 10 Further, in various embodiments, the copolymer may comprise at least one C4-C6 alpha-olefin in the range of 0.5 to 10, 1 to 10, 2 to 10, 3 to 10, 4 to 10, or 5 to 10 weight percent based on the total weight of the copolymer. 10 It may contain an alpha-olefin.

[0060] In certain embodiments, the propylene-ethylene copolymer is any C4-C 10 It may also be free of alpha-olefins.

[0061] In some embodiments, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer may have a triad tacticity of at least 52, 53, 54, 55, 56, 57, 58, 59, 60, or 61 percent mm content. Additionally or alternatively, the propylene-ethylene copolymer may have a triad tacticity of less than 75, 74, 73, 72, 71, 70, 69, 68, 67, 66, 65, 64, 63, 62, 61, or 60 percent mm content.

[0062] In some embodiments, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer may have a triad stereoregularity in the range of 52 to 75, 52 to 74, 52 to 70, 52 to 65, 52 to 60, 53 to 75, 53 to 74, 53 to 70, 53 to 65, 53 to 60, 54 to 75, 54 to 74, 54 to 70, 54 to 67, 54 to 66, 54 to 65, 54 to 60, 55 to 75, 55 to 74, 55 to 70, 55 to 65, 55 to 60, 58 to 75, 58 to 74, 58 to 70, 58 to 68, 60 to 75, 60 to 74, 60 to 70, 60 to 68, 61 to 75, 61 to 74, 61 to 70, or 61 to 68 mm content percent.

[0063] Equations for measuring triad tacticity can be found in U.S. Pat. No. 5,504,172 and in the paper by Tsutsui et al. (Polymer 1989, 30, 1350-1356), both of which are incorporated by reference in their entirety. The triad tacticity of a polymer is the relative tacticity of the sequence of three adjacent propylene units, a chain consisting of head-to-tail bonds, expressed as a binary combination of meso (m) and racemic (r) sequences. Triad tacticity, expressed herein as "mm", was determined by C nuclear magnetic resonance (NMR) and the following equation:

[0064]

number

[0065]

number

[0066] In some embodiments, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer may have a Brookfield viscosity at 190°C of at least 2,000, 3,000, 4,000, 5,000, 6,000, 7,000, 8,000, 9,000, 10,000, 11,000, 12,000, 13,000, 14,000, 15,000, 16,000, 20,000, 25,000, 27,000, 30,000, 35,000, 40,000, 45,000, 50,000, 55,000, 60,000, 65,000, 70,000, 75,000, 80,000, 85,000, 90,000 cP. Additionally or alternatively, the propylene-ethylene copolymer may be one that meets ASTM D-3236 of less than 120,000, 110,000, 100,000, 90,000, 88,000, 80,000, 70,000, 60,000, 50,000, 40,000, 35,000, 30,000, 27,000, 26,000, 25,000, 20,000, 18,000, 17,000, 16,000, 15,000, 14,000, 13,000, 12,000, 11,000, 10,000, 7,000, 6,000, 5,000, 4,000, 3,000, or 2,000 cP at 190°C.

[0067] In some embodiments, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer may have a higher Brookfield viscosity, as measured according to ASTM D-3236, in the range of 4,000 to 88,000, 15,000 to 88,000, 15,000 to 60,000, 15,000 to 26,000, 27,000 to 40,000, 27,000 to 35,000, 27,000 to 30,000, 15,000 to 26,000, 4,000 to 60,000, or 27,000 to 120,000 cP at 190° C. Additionally or alternatively, the propylene-ethylene copolymer may have a higher Brookfield viscosity, as measured according to ASTM D-3236, of greater than 15,000 cP and less than 88,000 cP at 190° C.

[0068] In some embodiments, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer may have a mid-Brookfield viscosity at 190°C, as measured according to ASTM D-3236, in the range of 7,000 to 15,000, 7,000 to 14,000, 7,000 to 13,000, or 7,000 to 12,000 cP.

[0069] In some embodiments, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer may have a low Brookfield viscosity at 190°C, as measured according to ASTM D-3236, in the range of 2,000 to 7,000, 3,000 to 7,000, 4,000 to 7,000, 4,000 to 27,000, 7,000 to 12,000, or 4,000 to 6,000 cP.

[0070] In certain embodiments, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer may have a peak Tm of at least 70, 72, 74, 75, 76, 78, 80, 82, 84, 85, 86, 88, or 90° C. Additionally or alternatively, the propylene-ethylene copolymer may have a peak Tm of less than 121, 120, 118, 116, 114, 112, 110, 108, 106, 104, 102, 100, 98, 96, 94, 92, 90, 89, 88, 87, 86, or 85° C. The peak Tm may be measured according to the procedure outlined in “DSC as Problem Solving Tool: Measurement of Percent Crystallinity of Thermoplastics” by Sichina et al., which is incorporated herein by reference in its entirety. Peak Tm refers to the assigned temperature that the DSC software identifies as the integrated peak of the melting transition from the Tm endotherm.

[0071] In some embodiments, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer may have a peak Tm in the range of 70 to 90°C, 70 to 89°C, 70 to 88°C, 70 to 87°C, 70 to 86°C, 70 to 85°C, 74 to 85°C, 85 to 121°C, or 90 to 110°C.

[0072] In general, the softening point of a propylene-ethylene copolymer can be modified and optimized by controlling the comonomer content, triad tacticity, crystallinity, and viscosity of the propylene-ethylene copolymer. A lower softening point of the copolymer may be desirable so that the copolymer can be utilized and processed at lower application temperatures. In some embodiments, or in combination with any embodiment described herein, the propylene-ethylene copolymer may exhibit a ring and ball softening point of at least 90°C, 94°C, 95°C, 100°C, 105°C, 110°C, 113°C, or 115°C, as measured according to ASTM E28 Standard Test Method for Softening Point of Resins Derived from Pine Chemicals and Hydrocarbons, by Ring and Ball Apparatus, using a heating rate of 5°C per minute and a bath of USP glycerin. Additionally or alternatively, the propylene-ethylene copolymer may exhibit a ring and ball softening point of less than 160°C, 155°C, 150°C, 145°C, 140°C, 138°C, 135°C, 134°C, 133°C, 130°C, 125°C, 120°C, 117°C, 115°C, or 110°C when measured according to ASTM E28 Standard Test Method for Softening Point of Resins Derived from Pine Chemicals and Hydrocarbons, by Ring and Ball Apparatus, using a heating rate of 5°C per minute and a bath of USP glycerin.

[0073] In one embodiment, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer is a propylene-ethylene copolymer that meets ASTM E28 Standard Test Method for Softening Point of Resins Derived from Pine Chemicals and The composition may exhibit a ring and ball softening point in the ranges of 90-155°C, 90-135°C, 94-154°C, 94-110°C, 94-135°C, 95-155°C, 95-135°C, 95-125°C, 105-155°C, 105-140°C, 100-135°C, 100-134°C, 100-133°C, 100-130°C, 100-125°C, 100-120°C, 100-117°C, 100-110°C, 105-120°C, or 113-138°C, as measured in a ring and ball apparatus using a heating rate of 5°C per minute and a bath of USP glycerin.

[0074] Generally, the needle penetration of the propylene-ethylene copolymer can be modified and optimized by controlling the comonomer content, triad tacticity, crystallinity, and viscosity of the propylene-ethylene copolymer. In some embodiments, or in combination with any embodiment described herein, the propylene-ethylene copolymer can have a needle penetration of at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, or 17 decimeters (dmm), as measured according to ASTM D5. Additionally or alternatively, the propylene-ethylene copolymer can have a needle penetration of less than 35, 30, 26, 25, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, or 11 dmm, as measured according to the ASTM D5 Standard Test Method for Penetration of Bituminous Materials.

[0075] In some embodiments, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer may have a needle penetration in the range of 2 to 26 dmm, 2 to 23 dmm, 3 to 23 dmm, 3 to 20 dmm, 5 to 23 dmm, 6 to 23 dmm, 10 to 23 dmm, 13 to 23 dmm, 6 to 22 dmm, 15 to 21 dmm, 17 to 22 dmm, 2 to 17 dmm, 2 to 15 dmm, 2 to 13 dmm, or 2 to 11 dmm.

[0076] Generally, the tensile strength at break of the propylene-ethylene copolymer can be modified and optimized by controlling the comonomer content, triad tacticity, crystallinity, and viscosity of the propylene-ethylene copolymer. In some embodiments, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer can exhibit a tensile strength at break of at least 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, or 4.0 MPa, as measured according to ASTM D412 Standard Test Methods for Vulcanized Rubber and Thermoplastic Elastomers—Tension. Additionally or alternatively, the propylene-ethylene copolymer may exhibit a tensile strength at break of less than 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2.5, or 2 MPa when measured according to ASTM D412.In an embodiment, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer has a modulus of elasticity, as measured according to ASTM D412, of 2 to 20 MPa, 2 to 17 MPa, 2 to 15 MPa, 2 to 12 MPa, 2 to 10 MPa, 2 to 9 MPa, 2 to 8 MPa, 2 to 6 MPa, 2 to 4 MPa, 2 to 3 MPa, 2 to 2.3 MPa, 2.5 to 20 MPa, 2.5 to 17 MPa, 2.5 to 15 MPa, 2.5 to 12 MPa, 2.5 to 10 MPa, 2.5 to 9 MPa, 2.5 to 8 MPa, 2.6 to 20 MPa, 2.6 to 17 MPa, 2.6 to 15 MPa, 2.6 to 12 MPa, 2.6 to 10 MPa Pa, 2.6-9 MPa, 2.6-8 MPa, 2.8-20 MPa, 2.8-17 MPa, 2.8-15 MPa, 2.8-12 MPa, 2.8-10 MPa, 2.8-9 MPa, 2.8-8 MPa, 3-20 MPa, 3-17 MPa, 3-15 MPa, 3-12 MPa, 3-10 MPa, 3-9 MPa, 3.5-20 MPa, 3.5-17 MPa, 3.5-15 MPa, 3.5-12 MPa, 3.5-10 MPa, 3.5-9 MPa, 3.5-8 MPa, 4-20 MPa, 4-15 MPa, 4-12 MPa, 4-10 MPa, 4-9 MPa, 4-8 MPa, or 4-6 MPa.

[0077] In general, the elongation at break of a propylene-ethylene copolymer may be modified and optimized by controlling the comonomer content, triad tacticity, crystallinity, and viscosity of the propylene-ethylene copolymer. In certain embodiments, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer may exhibit an elongation at break of at least 70, 100, 150, 200, 250, 300, 350, 400, 450, 500, 550, or 600%, as measured according to ASTM D412. Additionally or alternatively, the propylene-ethylene copolymer may exhibit an elongation at break of less than 1,000, 900, 800, 700, 600, or 500%, as measured according to ASTM D412.

[0078] In certain embodiments, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer may exhibit an elongation at break in the range of 70 to 1,000%, 70 to 800%, 70 to 500%, 100 to 1,000%, 100 to 800%, 200 to 1,000%, 200 to 800%, 300 to 1,000%, 300 to 800%, 450 to 1,000%, 450 to 800%, 500 to 1,000%, or 500 to 800%, as measured according to ASTM D412.

[0079] In some embodiments, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer has a heat of crystallization (H c Additionally or alternatively, the propylene-ethylene copolymer may exhibit a heat of crystallization (H ) of less than 50, 45, 42, 40, 38, 36, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, or 18 J / g. c For example, the propylene-ethylene copolymer may exhibit a heat of crystallization (H / g) in the range of 15-42, 15-33, 15-25, 15-24, 15-23, 15-22, 15-21, 15-20, 15-19, 15-18, 16-36, 16-33, 16-29, 16-22, 16-21, 16-20, 20-30, 20-28, 20-26, 23-42, or 24-29 J / g. c , 20°C / min cooling rate).

[0080] In an embodiment, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer has a heat of fusion (H fFor example, the propylene-ethylene copolymer may exhibit a heat of fusion (H / g) in the range of 8 to 40, 8 to 35, 9 to 33, 9 to 20, 9 to 18, 9 to 16, 9 to 15, 9 to 14, 10 to 29, 10 to 21, 11 to 29, 11 to 19, 11 to 16, 11 to 15, 11 to 14, 12 to 33, or 13 to 20 J / g. f , 20°C / min heating rate).

[0081] Additionally, the propylene-ethylene copolymers described herein can be amorphous or semi-crystalline. As used herein, "amorphous" means that the copolymer has a crystallinity of less than 5 percent as measured using Differential Scanning Calorimetry (DSC) in accordance with ASTM E 794-85. As used herein, "semi-crystalline" means that the copolymer has a crystallinity in the range of 5 to 40 percent as measured using DSC at a scan rate of 20°C / minute in accordance with ASTM E 794-85. In some embodiments, or in combination with any embodiment mentioned herein, the copolymer may have a crystallinity of at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 percent as measured using DSC in accordance with ASTM E 794-85. Additionally or alternatively, the copolymer may have a crystallinity of less than 60, 50, 45, 40, 35, 30, 25, 24, 23, or 22 percent, as measured using DSC in accordance with ASTM E 794-85. For example, the copolymer may have a crystallinity in the range of 2 to 50, 3 to 46, 4 to 40, 4 to 30, 4 to 20, 16 to 25, 16 to 23, 17 to 25, 17 to 23, 20 to 35, or 20 to 30 percent, as measured using DSC in accordance with ASTM E 794-85.

[0082] In some embodiments, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymers do not exhibit a substantial change in color when subjected to storage conditions at elevated temperatures for extended periods of time. Before any storage-related aging occurs, the copolymers of the present invention may have an initial Gardner color, as measured according to ASTM D1544, of less than 4, 3, 2, or 1. Additionally or alternatively, after heat aging at 177°C for at least 96 hours, the copolymers of the present invention may exhibit a final Gardner color, as measured according to ASTM D1544, of less than 7, 5, 3, or 2. Thus, the copolymers of the present invention may retain a desirable color even after extended storage and exposure.

[0083] In an embodiment, or in combination with any embodiment mentioned herein, the propylene-ethylene copolymer may contain ethylene in the range of 8 to 25 weight percent, based on the total weight of the copolymer, may have a triad tacticity in the range of 55 to 70 mm%, may have a tensile strength at break in the range of 0.9 to 10 MPa, as measured according to ASTM D412, a ring and ball softening point in the range of 100°C to 135°C, as measured according to ASTM E28, and a viscosity of 15,000 to 30,000 cP at 190°C, as measured according to ASTM D-3236.

[0084] Exemplary propylene-ethylene copolymer compositions having high viscosity and exhibiting high tensile strength and high elongation for use in various adhesives, such as woodworking adhesives, are provided below in Table 1A. As shown below, Table 1A provides broad, intermediate, and narrow ranges for various properties of these high-viscosity propylene-ethylene copolymers, and these ranges, regardless of their category, may be combined in any combination (e.g., one or more broad ranges may be combined with one or more intermediate and / or narrow ranges). Furthermore, although broad, intermediate, and narrow ranges are provided in Table 1A, it is contemplated that any of the ranges described above for propylene-ethylene copolymers in general may also be applied to the copolymer compositions provided in Table 1A, unless such ranges would create a conflict.

[0085] [Table 1]

[0086] Exemplary propylene-ethylene copolymer compositions for use in various adhesives, such as laminating adhesives and woodworking adhesives, having high viscosities and exhibiting intermediate tensile strengths are provided below in Table 1B. As shown below, Table 1B provides broad, intermediate, and narrow ranges for various properties of these high-viscosity propylene-ethylene copolymers, which may be combined in any combination regardless of their category (e.g., one or more broad ranges may be combined with one or more intermediate and / or narrow ranges). Furthermore, although broad, intermediate, and narrow ranges are provided in Table 1B, it is contemplated that any of the ranges described above for propylene-ethylene copolymers in general may also be applied to the copolymer compositions provided in Table 1B, unless such ranges would create a conflict.

[0087] [Table 2]

[0088] Exemplary propylene-ethylene copolymer compositions for use in various adhesives, such as sanitary adhesives, having medium viscosity and exhibiting medium tensile strength are provided below in Table 1C. As shown below, Table 1C provides broad, intermediate, and narrow ranges for various properties of these medium-viscosity propylene-ethylene copolymers, which may be combined in any combination regardless of their category (e.g., one or more broad ranges may be combined with one or more intermediate and / or narrow ranges). Furthermore, although broad, intermediate, and narrow ranges are provided in Table 1C, it is contemplated that any of the ranges described above for propylene-ethylene copolymers in general may also be applied to the copolymer compositions provided in Table 1C, unless such ranges would create a conflict.

[0089] [Table 3]

[0090] Exemplary propylene-ethylene copolymer compositions having low viscosity and exhibiting intermediate tensile strength for use in various adhesives, such as packaging and sanitary adhesives, are provided below in Table 1D. As shown below, Table 1D provides broad, intermediate, and narrow ranges for various properties of these low-viscosity propylene-ethylene copolymers, which may be combined in any combination regardless of their category (e.g., one or more broad ranges may be combined with one or more intermediate and / or narrow ranges). Furthermore, although broad, intermediate, and narrow ranges are provided in Table 1D, it is contemplated that any of the ranges described above for propylene-ethylene copolymers in general may also be applied to the copolymer compositions provided in Table 1D, unless such ranges would create a conflict.

[0091] [Table 4]

[0092] Process for producing propylene-ethylene copolymers As mentioned above, the present disclosure relates to a group of propylene-ethylene copolymers that exhibit desirable tensile properties at processable viscosities and moderate ring and ball softening points, and therefore can be utilized in a variety of adhesives. Without wishing to be bound by theory, it is believed that the unique tensile properties and ring and ball softening points are obtained due to the combination of several different copolymer characteristics, such as the propylene / ethylene content of the copolymer, the triad tacticity content (mm%) of the copolymer, the heat of crystallization of the copolymer, and the tackiness of the copolymer. Additionally, it has been observed that certain process conditions can also promote the production of the copolymers of the present invention described herein. As discussed below, it has been observed that certain reaction conditions (e.g., polymerization temperature) and catalyst system components (e.g., external donor to catalyst ratio) can significantly affect the resulting propylene-ethylene copolymer.

[0093] Propylene-ethylene copolymers may be produced by reacting propylene and ethylene monomers in the presence of a catalyst system that includes at least one electron donor.

[0094] In some embodiments, or in combination with any embodiment described herein, the catalyst system can include a Ziegler-Natta catalyst. Generally, the Ziegler-Natta catalyst can include a titanium-containing component, an aluminum component, and an electron donor. In certain embodiments, the catalyst includes titanium chloride on a magnesium chloride support.

[0095] In certain embodiments, or in combination with any embodiment mentioned herein, the catalyst system may include a heterogeneous supported catalyst system formed from a titanium compound in combination with an organoaluminum cocatalyst. Typically, the cocatalyst may include an alkylaluminum cocatalyst such as triethyl aluminum ("TEAL").

[0096] In certain embodiments, or in combination with any embodiment mentioned herein, the catalyst system may have an aluminum to titanium molar ratio of at least 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, or 15:1, and / or no greater than 100:1, 50:1, 35:1, or 25:1. Additionally or alternatively, the catalyst system may have an aluminum to titanium molar ratio ranging from 1:1 to 100:1, from 5:1 to 50:1, from 10:1 to 35:1, or from 15:1 to 25:1.

[0097] In some embodiments, or in combination with any embodiment mentioned herein, the catalyst system may have an aluminum to silicon molar ratio of at least 0.1:1, 0.5:1, 1:1, 2:1, 3:1, 4:1, 5:1, or 6:1, and / or no greater than 100:1, 50:1, 35:1, 20:1, 15:1, 10:1, or 8:1. Additionally or alternatively, the catalyst system may have an aluminum to silicon molar ratio ranging from 0.5:1 to 100:1, 1:1 to 50:1, 2:1 to 35:1, 2:1 to 20:1, 2:1 to 15:1, 2:1 to 10:1, or 2:1 to 8:1.

[0098] Generally, electron donors can enhance the stereospecificity of copolymers. However, it can be important to strictly control the content of electron donors, as they can suppress catalyst activity to unacceptable levels in some situations. Electron donors used during the polymerization process can include, for example, organic esters, ethers, alcohols, amines, ketones, phenols, phosphines, and / or organosilanes. Furthermore, the catalyst system can include internal donors and / or external donors.

[0099] As defined in "Stereospecific α-Olefin Polymerization with Heterogeneous Catalysts," by J. Severn and R.L. Jones Jr., Handbook of Transition Metal Polymerization Catalysts, (2018) Chapter 9, pp. 229-312 (incorporated herein by reference in its entirety), there are multiple generations of internal donors for Ziegler-Natta catalyst systems. Ziegler-Natta catalysts can be categorized into several generations, which are described in more detail below.

[0100] Ziegler-Natta 3rd Generation (Benzoate) Catalysts: 3rd generation catalysts typically contain MgCl2, TiCl4, and an internal electron donor, which are combined with an aluminum alkyl cocatalyst such as Al(CH2CH3)3. An external electron donor may be added to the catalyst system. The internal donor in 3rd generation catalysts is typically ethyl benzoate, which is used in combination with a second aromatic ester, such as methyl p-toluate or ethyl p-ethoxybenzoate (PEEB), as the external donor. The external donor is required because most of the internal donor is lost as a result of reactions involving the cocatalyst, such as alkylation and / or complexation reactions. To a large extent, the external donor replaces the internal donor in the solid catalyst, maintaining high catalytic stereospecificity.

[0101] Ziegler-Natta 4th Generation (Phthalate) Catalysts: 4th generation catalysts contain MgCl2, TiCl4, and an internal electron donor, which are combined with an aluminum alkyl cocatalyst such as Al(CH2CH3)3. An external electron donor can be added to the catalyst system. The internal donor in the 4th generation catalyst is a phthalate / alkoxysilane system. It has been found that bidentate phthalate donors can form strong chelate complexes with the tetracoordinate Mg atom on the (110) face of MgCl2 or binuclear complexes with the two pentacoordinate Mg atoms on the (100) face.

[0102] Ziegler-Natta catalysts, 5th generation (diethers and succinates): Certain diether compounds, especially those with oxygen-oxygen distances

[0103]

number

[0104] Ziegler-Natta 6th Generation Catalysts (Phthalate Substitution): The new 1,2-phenylenedibenzoate internal donor used in 6th Generation Ziegler-Natta catalysts is important as a phthalate substitute. In addition, there has been an increase in disclosure of mixed internal donors, such as blends of succinate and diether, or succinate and dimethoxytoluene. 6th Generation catalysts can also produce high stereospecificity in the absence of external donors. Therefore, depending on the crystallinity target, external donors may or may not be used to achieve the desired crystallinity target.

[0105] In certain embodiments, or in combination with any embodiment mentioned herein, the catalyst system may include a third generation Ziegler-Natta catalyst, a fourth generation Ziegler-Natta catalyst, a fifth generation Ziegler-Natta catalyst, or a sixth generation Ziegler-Natta catalyst.

[0106] In some embodiments, or in combination with any embodiment mentioned herein, the catalyst system may include a third generation Ziegler-Natta catalyst or a fourth generation Ziegler-Natta catalyst.

[0107] Generally, the catalyst system includes at least one external electron donor. In some embodiments, or in combination with any embodiment mentioned herein, the external electron donor includes at least one alkoxysilane, such as a "D" donor (e.g., dicyclopentyldimethoxysilane), a "C" donor (e.g., cyclohexylmethyldimethoxysilane), or a combination thereof. Furthermore, in some embodiments, the alkoxysilane can include, consist essentially of, or consist entirely of a "D" donor or a "C" donor.

[0108] It has been observed that the addition of the external donor to the catalyst system can increase the hardness (i.e., decrease the penetration) and increase the viscosity of the copolymer. However, contrary to previous observations in the art, the electron donor may decrease the softening point of the copolymer produced, instead of increasing it. Furthermore, it has been observed that substantially all (i.e., more than 95 percent) of the ethylene added to the reactor during the polymerization process can react when the electron donor is used. This can therefore result in a copolymer having a higher ethylene content and a lower propylene content. As a result, when the electron donor is used, a propylene-ethylene copolymer having a higher ethylene content but still exhibiting a desired balance between softening point and hardness can be produced.

[0109] In certain embodiments, or in combination with any embodiment mentioned herein, the catalyst system may have a molar ratio of external electron donor to titanium of at least 0.1:1, 0.5:1, 1:1, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1, or 4:1, and / or less than 10:1, 9:1, or 8:1. Additionally or alternatively, the catalyst system may have a molar ratio of external electron donor to titanium of between 0.1:1 and 10:1, between 0.5:1 and 10:1, between 1:1 and 10:1, between 1.5:1 and 10:1, between 2:1 and 10:1, between 2.5:1 and 10:1, between 3:1 and 10:1, between 3.5:1 and 10:1, between 4:1 and 10:1, between 0.5:1 and 9:1, between 1:1 and 9:1, between 1.5:1 and 9:1, between 2 ...10:1 and 10:1, between 10:1 and 10:1, between 10:1 and 10:1, between 10:1 and 10:1, between 10:1 and 10 The molar ratio of external electron donor to titanium may range from 0.5:1 to 8:1, 1:1 to 8:1, 1.5:1 to 8:1, 2:1 to 8:1, 2.5:1 to 8:1, 3:1 to 8:1, 3.5:1 to 8:1, or 4:1 to 8:1.

[0110] Additionally or alternatively, in some embodiments, or in combination with any embodiment mentioned herein, the catalyst system can include a molar ratio of TEAL cocatalyst to electron donor of at least 0.5:1, 1:1, 2:1, 3:1, 4:1, 5:1, or 6:1, and / or no greater than 100:1, 50:1, 35:1, 20:1, 15:1, 10:1, or 8:1. Further, the catalyst system can include a molar ratio of TEAL cocatalyst to electron donor ranging from 0.5:1 to 100:1, 1:1 to 50:1, 2:1 to 35:1, 2:1 to 20:1, 2:1 to 15:1, 2:1 to 10:1, or 2:1 to 8:1.

[0111] In certain embodiments, the type of electron donor can affect the required TEAL / electron donor ratio. For example, in embodiments where the electron donor is a "D" donor or a "C" donor, the TEAL / electron donor ratio can be less than 20:1.

[0112] The catalyst system may exhibit catalytic activities ranging from 200 to 2,000, 400 to 1,200, 500 to 1,000, 1,000 to 6,000, or 6,000 to 18,000 g / g. The catalytic activity is calculated by measuring the ratio of the weight of polymer produced in the reactor to the weight of catalyst loaded in the reactor. These measurements are based on a 1-hour reaction time.

[0113] Because the addition of external donors can increase viscosity and molecular weight, the addition of hydrogen may be required to act as a chain terminator during polymerization. For example, the process may be run at hydrogen pressures ranging from 5 to 100, 10 to 80, or 15 to 50 psig.

[0114] In certain embodiments, or in combination with any embodiment mentioned herein, the polymerization reaction can occur at a temperature of 160° C. or less, 155° C. or less, 150° C. or less, or in the ranges of 100-200, 110-180, 110-155, 120-160, or 120-150° C. Additionally, the polymerization reaction can be carried out at a pressure in the ranges of 500-2,000, 600-1,500, 700-1,250, or 800-1,100 psig.

[0115] In certain embodiments, or in combination with any embodiment mentioned herein, the ratio of ethylene flow rate to propylene flow rate to the polymerization reaction is from 0.1:100 to 18:100, from 0.1:100 to 10:100, from 0.1:100 to 5:100, from 0.1:100 to 4:100, from 0.5:100 to 3:100, from 0.5:100 to 2:100, from 0.5:100 to 1.5:100, from 0.5:100 to 1:100, from 1:100 to 4:100, from 1:100 to 3:100, from 1:100 to 2:100, from 1.5:100 to 4:100, from 1.5:100 to 3:100, from 1.5:100 to 1.5:100 It may be in the range of 0 to 2:100, 2:100 to 4:100, 2:100 to 3:100, 3:100 to 18:100, 3:100 to 14:100, 3:100 to 12:100, 3:100 to 10:100, 4:100 to 18:100, 4:100 to 14:100, 4:100 to 12:100, 4:100 to 10:100, 7:100 to 18:100, 7:100 to 14:100, 7:100 to 12:100, 7:100 to 10:100, 8:100 to 18:100, 8:100 to 14:100, 8:100 to 12:100, or 8:100 to 10:100.

[0116] In certain embodiments, or in combination with any embodiment referred to herein, the ratio of hydrogen flow rate to propylene flow rate to the polymerization reaction can be in the range of 0.03:100 to 0.5:100, 0.04:100 to 0.4:100, 0.15:100 to 0.4:100, 0:100 to 0.3:100, 0:100 to 0.2:100, 0:100 to 0.02:100, 0:100 to 0.01:100, 0.01:100 to 0.02:100, 0.04:100 to 0.2:100, 0.05:100 to 0.1:100, 0.07:100 to 0.3:100, or 0.08:100 to 0.4:100.

[0117] In some embodiments, or in combination with any embodiment mentioned herein, the polymerization reactor may include a stirred reactor, and the polymerization reaction may have a residence time in the reactor ranging from 0.1 to 6, 0.5 to 4, 1 to 2, 6 to 72, 16 to 36, 16 to 24, 12 to 48, or 12 to 24 hours.

[0118] In an embodiment, or in combination with any embodiment mentioned herein, the polymerization reactor may comprise a loop reactor, and the polymerization reaction may have a residence time in the reactor ranging from 8 to 72, 12 to 48, 12 to 24, or 16 to 36 hours.

[0119] In certain embodiments, or in combination with any embodiment mentioned herein, ethylene may be added to the reactor as a gas and propylene may be added as a liquid.

[0120] End Uses Containing Propylene-Ethylene Copolymers The inventive propylene-ethylene copolymers described herein and compositions comprising these copolymers can be used in, for example, adhesives (e.g., automotive adhesives, woodworking adhesives, packaging adhesives), sealants, caulking compounds, roofing membranes, waterproofing membranes, compounds and underlayments, carpets, laminates, laminated articles, tapes (e.g., tamper-evident tapes, water-activated tapes, pressure-sensitive tapes, sealing tapes, scrim-reinforced tapes, veneer tapes, reinforced and non-reinforced adhesive paper tapes, boxmaker tapes, paper tapes, packaging tapes, HVAC duct tapes, masking tapes, invisible tapes, electrical tapes, gaffer tapes, hockey tapes, medical tapes, etc.), labels (e.g., general purpose labels, beverage labels, freezer labels, smart labels, consumer electronics tapes, etc.), and the like. and the like), mastics, polymer blends, wire coatings, molded articles, heat seal coatings, disposable hygiene products, insulating glass (IG) units, bridge decks, waterproofing membranes, waterproofing compounds, bitumen modification, asphalt modification, cable flooding / filling compounds, sheet molding compounds, dough molding compounds, overmolding compounds, rubber compounds, polyester composites, glass composites, glass fiber reinforced plastics, plastic fiber reinforced compounds, wood plastic composites, polyacrylic blend compounds, lost wax precision casting, investment casting wax compositions, candles, windows, films, gaskets, seals, O-rings, automotive molded parts, automotive extruded parts, clothing, rubber additives / processing aids, and fibers.

[0121] Films comprising the inventive propylene-ethylene copolymers described herein and compositions comprising these copolymers include, but are not limited to, multilayer films, coextruded films, calendered films, and cast films. Laminates comprising the inventive propylene-ethylene polymers or compositions comprising the inventive propylene-ethylene polymers include, but are not limited to, paper-foil laminates, paper-film laminates, and nonwoven-film laminates.

[0122] Adhesive compositions comprising the inventive propylene-ethylene copolymers described herein and compositions comprising these copolymers may include packaging adhesives, food contact grade adhesives, indirect food contact packaging adhesives, product assembly adhesives, woodworking adhesives, edge banding adhesives, profile wrapping adhesives, flooring adhesives, automotive assembly adhesives, structural adhesives, mattress adhesives, pressure sensitive adhesives (PSA), PSA tapes, PSA labels, PSA protective films, cling films, laminating adhesives, flexible packaging adhesives, heat seal adhesives, industrial adhesives, sanitary nonwoven construction adhesives, sanitary core integrity adhesives, and sanitary elastic attachment adhesives.

[0123] In some embodiments, or in combination with any embodiment described herein, the propylene-ethylene copolymers described herein can be utilized in adhesives such as hot melt adhesives, water-based adhesives, solvent-based adhesives, hot melt pressure-sensitive adhesives, solvent-based pressure-sensitive adhesives, hot melt nonwoven / hygienic adhesives, hot melt product assembly adhesives, hot melt woodworking adhesives, hot melt automotive part assembly adhesives, hot melt laminating adhesives, and hot melt packaging adhesives. More specifically, adhesives produced from the copolymers of the present invention can be utilized in a wide variety of end products, including hygienic packaging, home appliances, automotive parts, woodworking, and packaging applications requiring heat resistance, due to their unique combination of tensile strength, elongation at break, softening point, and needle penetration, as described above. In general, various properties of the copolymers of the present invention, such as tensile strength, elongation at break, softening point, and needle penetration, can be selected to suit the intended end use of the composition incorporating the copolymer.

[0124] In some embodiments, or in combination with any of the embodiments mentioned herein, the copolymers of the present invention may be used to produce adhesive compositions useful for packaging, product assembly, heat sealing, lamination, gap sealing (e.g., cable filling), caulking, window sealants, woodworking, edge banding, and / or profile wrapping. As used herein, the terms "adhesive," "adhesive composition," and "composition" may be used interchangeably.

[0125] In some embodiments, or in combination with any embodiment described herein, the adhesive composition comprises a hot melt adhesive. The hot melt adhesive can be applied to a substrate while in its molten state and allowed to cool to harden the adhesive layer. Such adhesives are widely used in a variety of commercial and industrial applications, such as product assembly, lamination, and packaging. In these applications, the adhesive is applied to at least one substrate to bond the substrate to a second similar or dissimilar substrate.

[0126] Adhesive, sealant, and other formulators, compounders, and users generally desire thermally stable, low color hot melt adhesives that have a favorable balance of physical properties, including temperature resistance, chemical resistance, cohesive strength, viscosity, adhesion to various substrates, and open and cure times that can be tailored to specific use and application conditions. The desired balance of properties varies depending on the application, and the inventive hot melt compositions described herein provide an improved balance of properties for multiple end uses.

[0127] The hot melt adhesive composition may have a melt rheology and thermal stability suitable for use in conventional hot melt adhesive application equipment. In some embodiments, or in combination with any of the embodiments mentioned herein, the blended components of the hot melt adhesive composition have a low melt viscosity at the application temperature, which facilitates the flow of the composition through coating equipment, such as a coating die or nozzle.

[0128] The hot melt adhesive compositions are useful for bonding a variety of substrates including, for example, cardboard, coated cardboard, paperboard, fiberboard, virgin and recycled kraft, high-density and low-density kraft, chipboard, treated and coated kraft and chipboard and corrugated versions thereof, clay-coated chipboard carton stock, composites, leather, polymeric films (e.g., polyolefin films (e.g., polyethylene and polypropylene), polyvinylidene chloride films, ethylene vinyl acetate films, polyester films, metallized polymeric films, multilayer films, and combinations thereof), fibers and substrates made from fibers (e.g., virgin fibers, recycled fibers, synthetic polymer fibers, cellulose fibers, and combinations thereof), release liners, porous substrates (e.g., woven webs, nonwoven webs, nonwoven scrims, and perforated films), cellulosic substrates, sheets (e.g., paper and fiber sheets), paper products, tape backings, and combinations thereof. Useful composites include, for example, chipboard laminated to metal foil (e.g., aluminum foil), which may optionally be laminated to at least one layer of polymeric film, chipboard bonded to film, kraft bonded to film (e.g., polyethylene film), and combinations thereof.

[0129] Hot melt adhesive compositions are useful for bonding a first substrate to a second substrate in a variety of applications and structures including, for example, packaging, bags, boxes, cartons, cases, trays, multi-wall bags, articles including accessories (e.g., straws attached to beverage boxes), ream wrap, cigarettes (e.g., plug wrap), filters (e.g., pleated filters and filter frames), bookbinding, footwear, disposable absorbent articles (e.g., disposable diapers, sanitary napkins, medical dressings, bandages, surgical pads, drapes, gowns, and meat packaging products), paper products, paper towels, toilet paper, facial tissue, wipes, tissue, sheeting, veneer, mattress covers, automotive foil, and components of absorbent articles such as absorbent elements, absorbent cores, impermeable layers, acquisition layers, woven and nonwoven webs, and combinations thereof.

[0130] The hot melt adhesive compositions are also useful for forming laminates of porous substrates and polymeric films, such as those used in the manufacture of disposable articles including, for example, medical drapes, medical gowns, sheets, feminine hygiene articles, diapers, adult incontinence articles, absorbent pads for animals (e.g., pet pads) and humans (e.g., body and cadaver), and combinations thereof.

[0131] The hot melt adhesive composition can be applied to a substrate in any useful form, including, for example, as a fiber, as a coating (e.g., a continuous or discontinuous coating), as beads, as a film (e.g., a continuous or discontinuous film), and combinations thereof. Furthermore, the hot melt adhesive may be applied using any suitable application method, including, for example, slot coating, curtain coating, spray coating (e.g., spiral spray, random spray, and meltblowing), foaming, extrusion (e.g., paint application, fine wire extrusion, single screw extrusion, and twin screw extrusion), wheel coating, non-contact coating, contact coating, gravure, engraved roller, roll coating, transfer coating, screen printing, flexographic printing, and combinations thereof.

[0132] In some embodiments, or in combination with any of the embodiments mentioned herein, the hot melt adhesives may be used to form automotive interior materials.

[0133] In general, the hot melt adhesives of the present invention can be used to form bonds to produce laminates and multi-layer laminates. As used herein, the terms "laminate" and "multi-layer laminate" can be used interchangeably.

[0134] The inventive composition of the present disclosure can be bonded to adherends including, but not limited to, cellulose-based polymer materials such as paper, cotton, linen, cloth, and wood boards; polyolefin resins such as polypropylene (PP) and polyethylene (PE); styrene resins such as polystyrene, styrene-butadiene block copolymers (SBS resins), styrene-acrylonitrile copolymers (AS resins), acrylonitrile-ethylene / propylene-styrene copolymers (AES resins), and acrylonitrile-butadiene-styrene copolymers (ABS resins); polycarbonate resins (PC resins), PC-ABS resins, (meth)acrylic resins, polyester resins, polyamide resins such as nylon and polyurethane, phenolic resins, and epoxy resins; wood; metal materials; plastic materials; elastomer materials; composite materials; textile materials; glass materials; leather materials, and combinations thereof. The adherend material can be a mixture or combination of two or more different materials. When a laminate is formed by bonding two different adherends via an adhesive layer comprising the inventive propylene-ethylene polymer or hot melt adhesive of the present disclosure, the materials of the two adherends can be the same or different from each other.

[0135] Laminates containing the polymer or composition of the present invention can be suitably used in applications where coated materials and formed articles are used as adherends, such as interior materials for automobiles and the like (e.g., automobile interior ceiling materials, automobile interior door parts, automobile interior dashboard parts, instrument panels, etc.), home appliance parts (e.g., personal computer housings, flat-screen television frames, etc.), and housing materials (e.g., interior wall panels, decorative films, etc.).

[0136] In some embodiments, or in combination with any of the embodiments mentioned herein, a multilayer laminate can be prepared by bonding a formed article with a covering material, such as a decorative sheet, via an adhesive layer comprising the propylene-ethylene polymer or hot melt adhesive composition of the present invention. Various preparation methods, such as heat lamination, vacuum forming, vacuum-pressure forming, hot pressing, hot rolling, and / or hot stamping, can be used.

[0137] Typical, but non-limiting, industrial applications of hot melt adhesive compositions include packaging, woodworking, vehicle (e.g., automobile) interior component assembly, and traditional end uses (e.g., bookbinding, sanitary disposable consumer articles, and labeling).

[0138] In some embodiments, or in combination with any of the embodiments mentioned herein, the inventive copolymers described herein can also be used to modify existing polymer blends typically utilized in plastics, elastomer applications, roofing applications, cable filling, and tire modification. The inventive copolymers can improve the adhesion, processability, stability, viscoelasticity, thermal, and mechanical properties of these polymer blends.

[0139] In some embodiments, or in combination with any of the embodiments described herein, the propylene-ethylene copolymers of the present invention can be modified to produce graft copolymers. In such embodiments, the copolymers of the present invention can be grafted with maleic anhydride, fumaric and maleic acid esters, methacrylic acid esters (e.g., glycidyl methacrylate and hydroxyethyl methacrylate), methacrylic acid, vinyl derivatives, silane derivatives, or combinations thereof. These graft copolymers can be produced using any conventional process known in the art, including, for example, transesterification and free-radical induced coupling.

[0140] The various end uses and end products described above may utilize the copolymer of the present invention by itself or may combine it with other additives and polymers. Suitable polymers that can be combined with the copolymers of the present invention to form polymer blends include, for example, isoprene-based block copolymers; butadiene-based block copolymers; hydrogenated block copolymers; styrene-ethylene / butylene-styrene block copolymers (SEBS); styrene-isoprene-styrene block copolymers (SIS); styrene-ethylene / propylene-styrene (SEPS); ethylene-vinyl acetate copolymers; polyesters; polyester-based copolymers; neoprene; urethanes; acrylics; polyacrylates; acrylate copolymers, such as, but not limited to, ethylene-acrylic acid copolymer, ethylene-n-butyl acrylate copolymer, and ethylene-methyl acrylate copolymer; polyether ether ketone; polyamides; styrene block copolymers; hydrogenated styrene block copolymers; random styrene copolymers; ethylene-propylene rubber; ethylene-vinyl acetate copolymer; butyl rubber; styrene-butadiene rubber; butadiene-acrylonitrile rubber; natural rubber; polyisoprene; polyisobutylene; polyvinyl acetate; polyolefins; and combinations thereof.

[0141] The polyolefin used with the propylene-ethylene copolymer of the present invention can be any known in the art. In some embodiments, or in combination with any embodiment mentioned herein, the polyolefin can be an amorphous polyolefin, a semi-crystalline polyolefin, an alpha-polyolefin, a reactor-ready polyolefin, a metallocene-catalyzed polyolefin polymer and elastomer, a reactor-made thermoplastic polyolefin elastomer, an olefin block copolymer, a thermoplastic polyolefin, an atactic polypropylene, a polyethylene, an ethylene-propylene polymer, a propylene-hexene polymer, an ethylene-butene polymer, an ethylene-octene polymer, a propylene-butene polymer, a propylene-octene polymer, a metallocene-catalyzed polypropylene polymer, a metallocene-catalyzed polyethylene polymer, a propylene-based terpolymer, propylene and a linear or branched C4-C6 10 Copolymers made from alpha-olefin monomers, ethylene and linear or branched C4-C 10 It can be at least one selected from the group consisting of copolymers made from alpha-olefin monomers, and functionalized polyolefins.

[0142] Functionalized olefin polymers and copolymers include maleated polyethylene, maleated metallocene polyethylene, maleated metallocene polypropylene, maleated ethylene propylene rubber, maleated polypropylene, maleated ethylene copolymers, functionalized polyisobutylene (typically functionalized with maleic anhydride, typically to form succinic anhydride), and the like.

[0143] It has been found that blends of the propylene-ethylene copolymers of the present invention with various types of polyolefins can provide adhesives with improved adhesion, cohesive strength, temperature resistance, viscosity, and open and cure times. Thus, in various embodiments, the propylene-ethylene polymers of the present invention may be combined with at least one polyolefin.

[0144] As mentioned above, the propylene-ethylene copolymers of the present invention described herein can be used to produce hot melt adhesives. In some embodiments, or in combination with any of the embodiments mentioned herein, the adhesive composition can comprise at least 1, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 30, 32, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 weight percent of one or more propylene-ethylene copolymers, based on the total weight of the adhesive. Additionally or alternatively, the adhesive composition may comprise less than 95, 90, 85, 80, 76, 75, 70, 66, 63, 60, 59, 56, 55, 52, 50, 45, 40, 35, 30, 25, 20, 15, or 10 weight percent of one or more propylene-ethylene copolymers, based on the total weight of the adhesive.

[0145] In certain embodiments, or in combination with any embodiment mentioned herein, the adhesive composition can comprise in the range of 1 to 95, 5 to 90, 5 to 100, 8 to 52, 8 to 50, 8 to 45, 8 to 35, 10 to 80, 20 to 70, 25 to 52, 25 to 50, 25 to 45, 30 to 45, 30 to 60, 35 to 50, 35 to 55, 40 to 55, 50 to 80, 50 to 70, 30 to 90, 30 to 80, 30 to 70, 30 to 60, 30 to 50, or 30 to 40 weight percent of one or more propylene-ethylene copolymers, based on the total weight of the adhesive. In certain embodiments, the adhesive composition can consist entirely of the copolymers of the present invention.

[0146] In some embodiments, or in combination with any embodiment mentioned herein, the adhesive may contain at least one, two, or three inventive propylene-ethylene copolymers selected from Tables 1A, 1B, 1C, and / or 1D. In such embodiments, the copolymers may include any combination of high viscosity copolymers (i.e., Table 1B), medium viscosity copolymers (i.e., Table 1C), and / or low viscosity copolymers (i.e., Table 1D).

[0147] Additionally, depending on the intended end use, the hot melt adhesive composition may also contain various additives including, for example, second polymers, tackifiers, processing oils, waxes, antioxidants, plasticizers, pigments, and fillers.

[0148] In certain embodiments, or in combination with any embodiment mentioned herein, the adhesive composition may comprise at least 1, 2, 3, 4, 5, 10, 12, 15, 20, 30, 40, 50, or 55 weight percent of at least one second polymer different from the copolymer of the present invention. Additionally or alternatively, the adhesive composition may comprise no more than 90, 80, 70, 55, 40, 35, 30, 25, 20, 15, 14, 13, 12, 11, or 10 weight percent of at least one second polymer different from the copolymer of the present invention. For example, the adhesive may comprise in the range of 10 to 90, 20 to 80, 30 to 70, 40 to 55, 1 to 15, 1 to 3, 1 to 5, 1 to 20, 2 to 15, or 2 to 10 weight percent of at least one second polymer different from the copolymer of the present invention.

[0149] In certain embodiments, or in combination with any embodiment mentioned herein, the adhesive composition may include at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 15, 17, 20, 23, 25, 30, 35, 40, 45, 47, or 50 weight percent of at least one second polymer different from the copolymer of the present invention.

[0150] Exemplary second polymers include amorphous polyolefins, semi-crystalline polyolefins, alpha-polyolefins, reactor-ready polyolefins, metallocene-catalyzed polyolefin polymers and elastomers, reactor-made thermoplastic polyolefin elastomers, olefin block copolymers, thermoplastic polyolefins, atactic polypropylene, polyethylene, ethylene-propylene polymers, propylene-hexene polymers, ethylene-butene polymers, ethylene-octene polymers, propylene-butene polymers, propylene-octene polymers, metallocene-catalyzed polypropylene polymers, metallocene-catalyzed polyethylene polymers, propylene-based terpolymers including ethylene-propylene-butylene-terpolymers, propylene and linear or branched C4-C6 10 Copolymers made from alpha-olefin monomers, ethylene and linear or branched C4-C 10 The polymer may include copolymers made from alpha-olefin monomers, functionalized polyolefins, isoprene-based block copolymers, butadiene-based block copolymers, hydrogenated block copolymers, styrene-ethylene / butylene-styrene block copolymers (SEBS), styrene-isoprene-styrene block copolymers (SIS), styrene-ethylene / propylene-styrene (SEPS), ethylene vinyl acetate copolymers, polyesters, polyester-based copolymers, neoprene, urethanes, acrylics, polyacrylates, ethylene acrylic acid copolymers, ethylene n-butyl acrylate copolymers, ethylene methyl acrylate copolymers, polyether ether ketones, polyamides, styrene block copolymers, hydrogenated styrene block copolymers, random styrene copolymers, ethylene-propylene rubber, ethylene vinyl acetate copolymers, butyl rubber, styrene butadiene rubber, butadiene acrylonitrile rubber, natural rubber, polyisoprene, polyisobutylene, polyvinyl acetate, or combinations thereof.

[0151] In some embodiments, or in combination with any embodiment mentioned herein, the adhesive containing at least one second polymer may contain at least one, two, or three inventive propylene-ethylene copolymers selected from Tables 1A, 1B, 1C, and / or 1D. In such embodiments, the copolymers may include any combination of high viscosity copolymers (i.e., Table 1B), medium viscosity copolymers (i.e., Table 1C), and / or low viscosity copolymers (i.e., Table 1D).

[0152] In certain embodiments, or in combination with any embodiment mentioned herein, the adhesive may comprise, in addition to the propylene-ethylene copolymer of the present invention, at least 1, 2, 3, 4, 5, 10, 12, 15, 20, 25, 30, 35, 40, 45, or 50 weight percent of at least one polyolefin. Additionally or alternatively, the adhesive composition may comprise, in addition to the propylene-ethylene copolymer of the present invention, up to 99, 95, 90, 85, 80, 75, 70, 65, 60, 55, 50, 45, 40, 35, 30, 25, 20, 15, 12, 11, 10, 5, or 2 weight percent of at least one polyolefin, based on the total weight of the adhesive. For example, the adhesive composition can include in the range of 1 to 90, 1 to 60, 1 to 40, 1 to 20, 10 to 90, 20 to 80, 20 to 40, 30 to 70, 30 to 40, 40 to 55, 10 to 15, 1 to 3, 1 to 5, 1 to 15, 1 to 10, 2 to 15, or 2 to 10 weight percent of at least one polyolefin, based on the total weight of the adhesive.

[0153] Commercially available examples of acceptable polyolefins include Aerafin™ 17 by Eastman; Aerafin™ 180 by Eastman; Rextac™ polymers made by REXtac LLC, including REXtac™ E-63, E-65, 2760, 2815, 2730, and 2830; polymers made by Evonik Industries, including Vestoplast™, Vestoplast™ 408, and 708; and Eastoflex™ by Eastman, including Eastoflex™ E1060 and P1010.

[0154] Some examples of metallocene-catalyzed polymers include polyolefins such as polyethylene, polypropylene, and copolymers thereof. Exemplary polypropylene-based elastomers include those sold by ExxonMobil Chemical under the trade name VISTAMAXX™ and those sold by Idemitsu Kosan (Japan) under the trade name L-MODU™, and exemplary polyethylene-based elastomers and plastomers include those sold by Dow Chemical Company under the trade names AFFINITY™, AFFINITY™ GA, INFUSE™, and ENGAGE™, those sold by ExxonMobil Chemical Company (Houston, Texas) under the trade name VISTAMAXX™, and those sold by Clariant under the trade name LlCOCENE™.

[0155] In some embodiments, or in combination with any embodiment mentioned herein, the olefin polymer may comprise a mixture of at least two different olefin polymers, for example, a blend comprising an olefin homopolymer and an olefin copolymer, a blend comprising different olefin homopolymers of the same or different monomers, a blend comprising different olefin copolymers, and various combinations thereof. Useful olefin polymers also include, for example, modified, unmodified, grafted, and non-grafted olefin polymers, unimodal olefin polymers, multimodal olefin polymers, and combinations thereof.

[0156] In many cases, these added polyolefins may increase the cohesive strength, adhesive properties, tack, low temperature flexibility, total crystallinity, and / or temperature resistance of the adhesive compositions of the present invention. Furthermore, the addition of such polyolefins may reduce the production costs of the composition due to their widespread availability.

[0157] In some embodiments, or in combination with any of the embodiments mentioned herein, an adhesive composition can include an inventive propylene-ethylene copolymer and a metallocene-catalyzed polyethylene copolymer, such as an ethylene-octene copolymer. In such embodiments, the inventive propylene-ethylene copolymer can be used to replace polyethylene in various types of adhesives, such as those used in packaging applications.

[0158] In some embodiments, or in combination with any embodiment mentioned herein, the added polymer and / or polyolefin may be functionalized at the polymer chain ends and / or pendant positions within the polymer with groups including, but not limited to, silane, acid anhydride such as maleic anhydride, hydroxyl, ethoxy, epoxy, siloxane, amine, amine siloxane, carboxy, and acrylate.

[0159] The additional polymers and polyolefins that can be added to the adhesive compositions of the present invention can be prepared using Ziegler-Natta catalysts, single-site catalysts (metallocene), multiple single-site catalysts, non-metallocene heteroaryl catalysts, or combinations thereof. The additional polymers can include combinations of amorphous, semi-crystalline, random, branched, linear, or block structures.

[0160] Generally, any conventional polymerization synthesis process can be used to prepare the additional polyolefin component. In some embodiments, or in combination with any of the embodiments described herein, one or more catalysts, typically metallocene or Ziegler-Natta catalysts, are used to polymerize the olefin monomer or monomer mixture. Polymerization methods include high-pressure, slurry, gas, bulk, suspension, supercritical, or solution phase, or a combination thereof. The catalyst can be in the form of a homogeneous solution, supported, or a combination thereof. Polymerization can be carried out by continuous, semi-continuous, or batch processes and can include the use of chain transfer agents, scavengers, or other such additives as deemed applicable.

[0161] In some embodiments, or in combination with any embodiment mentioned herein, the additional polymers are produced in single or multiple polymerization zones using a single polymerization catalyst. Metallocene (or heterophasic) polymers are typically made using multiple metallocene catalyst blends to achieve the desired heterophasic structure.

[0162] In some embodiments, or in combination with any of the embodiments mentioned herein, the crystalline content of the added polymer or polyolefin can increase the cohesive strength of the adhesive composition. Generally, formulations based on metallocene-polymerized semi-crystalline copolymers can eventually build up a sufficient crystalline content over time to achieve good cohesive strength in the formulation.

[0163] In certain embodiments, or in combination with any embodiment mentioned herein, the adhesive composition may comprise at least 1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 46, 47, 48, 50, 55, or 60 weight percent of at least one tackifier, based on the total weight of the adhesive. Additionally or alternatively, the adhesive composition may comprise no more than 90, 80, 70, 60, 55, 50, 45, 40, 35, 30, 25, 20, 15, 10, or 5 weight percent of at least one tackifier, based on the total weight of the adhesive. For example, the adhesive may comprise in the range of 5 to 90, 20 to 80, 20 to 40, 20 to 30, 30 to 70, 35 to 50, 35 to 55, 35 to 60, 40 to 50, 40 to 55, 40 to 60, or 45 to 50 weight percent of at least one tackifier, based on the total weight of the adhesive.

[0164] Generally, tackifiers can impart tackiness and adhesive properties to adhesives and reduce the viscosity of the adhesive. Lower viscosity can improve application flow characteristics, allowing for easier processing, lower energy requirements, and lower processing temperatures. Lower viscosity also helps the adhesive "wet out" or coat the surface substantially evenly and penetrate the substrate. Tackiness is required in most adhesive formulations to allow for proper bonding of articles before the hot melt adhesive solidifies. The desirability and selection of a particular tackifier can depend on the specific type of olefin copolymer and additional polymer used.

[0165] Suitable tackifiers may include, for example, cycloaliphatic hydrocarbon resins; C5 hydrocarbon resins; C5 / C9 hydrocarbon resins; aromatic-modified C5 resins; C9 hydrocarbon resins; pure monomer resins such as styrene or copolymers with alpha-methylstyrene, vinyl toluene, para-methylstyrene, indene, methylindene, C5 resins, and C9 resins; terpene resins; terpene phenolic resins; terpene styrene resins; rosin esters; modified rosin esters; fully or partially hydrogenated rosin liquid resins; fully or partially hydrogenated rosin esters; fully or partially hydrogenated modified rosin resins; fully or partially hydrogenated rosin alcohols; fully or partially hydrogenated C5 resins; fully or partially hydrogenated C5 / C9 resins; fully or partially hydrogenated aromatic-modified C5 resins; fully or partially hydrogenated C9 resins; fully or partially hydrogenated pure monomer resins; fully or partially hydrogenated C5 / cycloaliphatic resins; fully or partially hydrogenated C5 / cycloaliphatic / styrene / C9 resins; fully or partially hydrogenated cycloaliphatic resins; and combinations thereof. Exemplary commercially available hydrocarbon resins include Regalite™ hydrocarbon resins. In certain embodiments, the tackifier may include a functionalized tackifier.

[0166] In some embodiments, or in combination with any of the embodiments described herein, the adhesive composition may comprise at least 1, 2, 3, 4, 5, 7, 8, 9, or 10, and / or up to 40, 30, 25, 20, 15, 10.5, 10, 6, or 5 weight percent of at least one processing oil, based on the total weight of the adhesive. For example, the adhesive composition may comprise 2 to 40, 2 to 20, 2 to 15, 2 to 10.5, 2 to 5, 5 to 30, 8 to 25, 1 to 15, or 10 to 20 weight percent of at least one processing oil, based on the total weight of the adhesive. The processing oil may include, for example, mineral oil, naphthenic oil, paraffin oil, aromatic oil, castor oil, rapeseed oil, triglyceride oil, or a combination thereof. As will be appreciated by those skilled in the art, the processing oil may also include extender oils commonly used in adhesives. The use of oil in the adhesive may be desirable when the adhesive is used as a pressure sensitive adhesive to produce tapes or labels, or as an adhesive to adhere nonwoven articles. In certain embodiments, the adhesive may be free of any processing oils.

[0167] In certain embodiments, or in combination with any embodiment mentioned herein, the adhesive composition may include at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 15, 16, 17, 18, 19, 20, 21, 22, 23, or 25 weight percent of at least one wax, based on the total weight of the adhesive. Additionally or alternatively, the adhesive composition may include up to 40, 30, 25, 20, 15, 10, 7, 5, or 3 weight percent of at least one wax, based on the total weight of the adhesive. For example, the adhesive may include 1-40, 5-30, 8-25, 10-20, 3-7, 2-5, 2-7, 2-40, 2-30, 2-25, 2-20, 2-10, 1-25, 1-20, 1-15, 1-10, 1-7, or 1-5 weight percent of at least one wax. Waxes serve to reduce the overall viscosity of the adhesive, thereby liquefying the adhesive and allowing for proper application or coating of the hot melt adhesive onto the intended substrate. The type and melting point of the wax, as well as its compatibility with the other components of the adhesive composition, control the open time and cure rate of the adhesive. Open time is known in the art as the length of time an adhesive takes to wet out and bond to a substrate after application. Any conventionally known wax suitable for use in formulating hot melt adhesives may be used in the practice of the present invention.

[0168] Suitable waxes may include, for example, microcrystalline wax, paraffin wax, wax produced by the Fischer-Tropsch process, functionalized waxes (such as maleated wax, fumarated wax, or waxes with functional groups), polyolefin wax, petroleum wax, polypropylene wax, polyethylene wax, ethylene vinyl acetate wax, and vegetable wax. When the adhesive is used as a hot melt packaging adhesive, the use of waxes in the adhesive may be desirable.

[0169] Non-limiting examples of commercially available waxes suitable for the present invention include Sasol® H-1 available from Sasol Wax Americas, Inc.; AC™-9, AC-596, and AC 810 available from Honeywell International Inc.; EPOLENE™ N-15, E-43, C-10, and C-18 available from Westlake, and POLYWAX™ 400, 850, 1000, and 3000 from Baker Hughes Inc. Other exemplary waxes include, but are not limited to, microcrystalline wax Be Square™ 195 and Clariant Licocene™ PE4201.

[0170] As used herein, "functionalized" means that the relevant component is prepared in the presence of a functional group that is incorporated into the component or is contacted with the functional group, and optionally a catalyst, heat, initiator, or free radical source, to incorporate, graft, bond, physically attach, and / or chemically attach all or a portion of the functional group (such as maleic acid or maleic anhydride) to the polymer.

[0171] Exemplary functionalized wax polymers useful as functionalized components include those modified with alcohols, acids, ketones, anhydrides, and the like. Commercially available functionalized waxes include maleated polypropylene available from Chusei under the tradename MAPP40; maleated metallocene waxes (such as TP LICOCENE PP1602 available from Clariant); maleated polyethylene waxes and maleated polypropylene waxes available from Westlake under the tradenames EPOLENE C-16, EPOLENE C-18, and EPOLENE E43; EASTMAN G-3003 from Eastman Chemical; maleated polypropylene wax LICOMONT AR 504 available from Clariant; grafted functional polymers available from Dow Chemical Co. under the tradenames AMPLIFY EA 100 and AMPLIFY VA 200; and CERAMER maleated ethylene polymers available from Baker Hughes under the tradenames CERAMER 1608, CERAMER 1251, CERAMER 67, and CERAMER 24. Useful waxes also include polyethylene and polypropylene waxes having a Mw of less than 15,000, preferably 3,000-10,000, a crystallinity of 5 weight percent or greater, preferably 10 weight percent or greater, and a functional group content of up to 10 weight percent. Additional functionalized polymers that can be used as the functional component include AC 575P, AC 573P, AC X596A, AC X596P, AC X597A, AC X597P, AC X950P, AC X1221, AC 395A, AC 395A, AC 1302P, AC 540, AC 54A, AC 629, AC 629A, AC 307, and AC 307A, available from Honeywell International.

[0172] In some embodiments, or in combination with any of the embodiments mentioned herein, the adhesive composition may be wax-free. For example, the adhesive composition may include less than 10, 7, 5, 4, 3, 2, 1, or 0.5 weight percent of a wax, such as, but not limited to, polyethylene wax and / or Fischer-Tropsch wax.

[0173] In certain embodiments, or in combination with any embodiment mentioned herein, the adhesive composition can include at least 0.1, 0.2, 0.5, 1, 2, or 3, and / or no more than 20, 10, 8, 5, 1, or 0.5 weight percent of at least one antioxidant, based on the total weight of the adhesive. For example, the adhesive composition can include in the range of 0.1 to 20, 1 to 10, 2 to 8, 3 to 5, or 0.5 to 2 weight percent of at least one antioxidant.

[0174] In certain embodiments, or in combination with any embodiment mentioned herein, the adhesive composition can include at least 0.5, 1, 2, or 3, and / or up to 20, 10, 8, or 5 weight percent of at least one plasticizer, based on the total weight of the adhesive. For example, the adhesive can include 0.5 to 20, 1 to 10, 2 to 8, or 3 to 5 weight percent of at least one plasticizer. Suitable plasticizers can include, for example, olefin oligomers, low molecular weight polyolefins such as liquid polybutylene, polyisobutylene, mineral oil, dibutyl phthalate, dioctyl phthalate, chlorinated paraffins, and phthalate-free plasticizers. Commercially available plasticizers may include, for example, Benzoflex™ plasticizer (Eastman Chemical); Eastman 168™ (Eastman Chemical); Oppanol® B10 (BASF); REGALREZ 1018 (Eastman Chemical); Calsol 5550 (Calumet Lubricants); Kaydol oil (Chevron); or ParaLux oil (Chevron).

[0175] In certain embodiments, or in combination with any embodiment mentioned herein, the adhesive composition can include at least 5, 10, 20, 30, or 40, and / or up to 90, 80, 70, or 55 weight percent of at least one filler, based on the total weight of the adhesive. For example, the adhesive can include 1 to 90, 20 to 80, 30 to 70, or 40 to 55 weight percent of at least one filler. Suitable fillers can include, for example, carbon black, calcium carbonate, clay, titanium oxide, zinc oxide, or combinations thereof.

[0176] The adhesive composition can be produced using conventional techniques and equipment. For example, the components of the adhesive composition can be blended in a mixer such as a sigma blade mixer, a plasticorder, a Brabender mixer, a twin-screw extruder, or an in-can blend (pint can). In some embodiments, or in combination with any embodiment mentioned herein, the adhesive can be formed into a desired form, such as a tape or sheet, by a suitable technique including, for example, extrusion, compression molding, calendering, or roll coating techniques (e.g., gravure, reverse roll, etc.), curtain coating, slot die coating, or spray coating.

[0177] Additionally, the adhesive composition can be applied to a substrate by a solvent casting process or by melting the adhesive and then using conventional hot melt adhesive application equipment known in the art. Suitable substrates can include, for example, nonwoven fabrics, woven fabrics, paper, glass, plastics, films, wood, and metal. Generally, the adhesive composition can be applied at a concentration of 0.1 to 100 g / m. 2 or 1 to 1,000 g / m 2 The adhesive composition may be applied to a substrate.

[0178] In certain embodiments, or in combination with any embodiment mentioned herein, the hot melt adhesive composition may have a Brookfield viscosity at 177°C of at least 100, 300, 500, 750, or 1,000, and / or no more than 60,000, 40,000, 30,000, 20,000, 10,000, 5,000, 4,000, 3,000, or 2,500 cps, as measured according to ASTM D3236. For example, the hot melt adhesive may have a Brookfield viscosity at 177°C in the range of 100 to 60,000, 300 to 10,000, 500 to 5,000, 750 to 2,500, 400 to 3,000, 500 to 1,000, 500 to 5,000, 500 to 10,000, 500 to 15,000, 500 to 20,000, 1,000 to 5,000, 1,000 to 10,000, 1,000 to 15,000, 1,000 to 20,000, 1,000 to 40,000, or 1,000 to 60,000 cps.

[0179] In an embodiment, or in combination with any embodiment mentioned herein, the hot melt adhesive composition may have a Brookfield viscosity at 140°C of at least 100, 500, 1,000, 2,000, 3,000, 4,000, 5,000, 6,000, 7,000, 8,000, or 9,000, and / or no more than 60,000, 40,000, 30,000, 20,000, or 15,000 cps, as measured according to ASTM D3236. For example, the hot melt adhesive may have a Brookfield viscosity at 140°C in the range of 100 to 60,000, 500 to 20,000, 3,000 to 15,000, 4,000 to 15,000, 5,000 to 15,000, 5,000 to 15,000, or 6,000 to 15,000 cps.

[0180] In an embodiment, or in combination with any embodiment mentioned herein, the hot melt adhesive composition may have a Brookfield viscosity at 150°C of at least 100, 500, 1,000, 1,500, 2,000, 3,000, 4,000, 5,000, 6,000, 7,000, 8,000, or 9,000, and / or no more than 60,000, 40,000, 30,000, 20,000, or 15,000 cps, as measured according to ASTM D3236. For example, the hot melt adhesive may have a Brookfield viscosity at 150°C in the range of 100 to 60,000, 500 to 20,000, 1,000 to 15,000, 1,000 to 4,000, 2,000 to 15,000, 3,000 to 15,000, 4,000 to 15,000, or 4,000 to 10,000 cps.

[0181] In an embodiment, or in combination with any embodiment mentioned herein, the hot melt adhesive composition may have a Brookfield viscosity at 160°C of at least 100, 500, 1,000, 1,500, 2,000, 2,500, 3,000, 3,500, or 4,000, and / or no more than 60,000, 40,000, 30,000, 20,000, 10,000, 9,000, or 8,000 cps, as measured according to ASTM D3236. For example, the hot melt adhesive may have a Brookfield viscosity at 160°C in the range of 100 to 60,000, 500 to 10,000, 1,000 to 10,000, 1,500 to 10,000, 2,000 to 10,000, 1,000 to 8,000, 1,000 to 5,000, 1,000 to 4,000, or 2,000 to 10,000 cps.

[0182] In an embodiment, or in combination with any embodiment mentioned herein, the hot melt adhesive composition may have a Brookfield viscosity at 190°C of at least 100, 500, 1,000, 2,000, 3,000, 4,000, 5,000, 6,000, 7,000, 8,000, or 9,000, and / or no more than 60,000, 50,000, 40,000, 30,000, 20,000, or 15,000 cps, as measured according to ASTM D3236. For example, the hot melt adhesive may have a Brookfield viscosity at 190°C in the range of 100 to 60,000, 500 to 20,000, 1,000 to 5,000, 1,000 to 4,000, or 2,000 to 10,000, 1,000 to 20,000, 3,000 to 15,000, 4,000 to 15,000, 5,000 to 15,000, 5,000 to 15,000, or 6,000 to 15,000 cps.

[0183] In an embodiment, or in combination with any embodiment mentioned herein, the hot melt adhesive composition may have a 90 degree (T-peel) peel strength, measured according to ASTM D903, of at least 1, 2, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 90, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, or 150 g / 25 mm. Additionally or alternatively, the hot melt adhesive composition may have a 90 degree peel strength (T-peel), measured according to ASTM D903, of no more than 200, 190, 180, 170, 160, 150, 140, 130, 120, 110, 100, 95, 90, 85, or 80 g / 25 mm. The aforementioned peel strength values may be applicable after the adhesive has cured for 24 hours at room temperature, after the adhesive has cured for 4 hours at 38° C., after the adhesive has cured for 2 weeks at 55° C., and / or after the adhesive has cured for 1 month at 25° C. For example, the hot melt adhesive may have a peel strength in the range of 1 to 200, 10 to 180, 20 to 150, 30 to 140, 40 to 120, 55 to 200, 55 to 100, 55 to 150, 55 to 200, 70 to 200, 100 to 200, or 115 to 200 g / 25 mm when measured according to ASTM D903.

[0184] As mentioned above, due to the unique propylene-ethylene copolymer, the hot melt adhesive composition can exhibit desirable peel strength even after aging. In some embodiments, or in combination with any embodiment mentioned herein, the hot melt adhesive composition can exhibit a 90 degree (T-peel) peel strength in the range of 1 to 200, 10 to 180, 20 to 150, 30 to 140, 40 to 120, 55 to 200, 55 to 100, 55 to 150, 55 to 200, 70 to 200, 100 to 200, or 115 to 200 g / 25 mm when measured according to ASTM D903 after the adhesive has cured at room temperature for 24 hours, after the adhesive has cured at 38°C for 4 hours, after the adhesive has cured at 55°C for 2 weeks, and / or after the adhesive has cured at 25°C for 1 month. Additionally or alternatively, the hot melt adhesive composition may exhibit a 90 degree (T-peel) peel strength after 4 hours, 24 hours, 2 weeks, or 1 month aging that is at least 50, 55, 60, 65, 70, 75, 80, 85, or 90 percent of the initial 90 degree (T-peel) peel strength.

[0185] In general, adhesive compositions containing the copolymers of the present invention may have a wide operating window, with an application window of 80 to 230° C. This wide operating window may be demonstrated by the peel strength of the adhesive at different temperatures.

[0186] In certain embodiments, or in combination with any embodiment mentioned herein, the hot melt adhesive composition may exhibit a holding power of at least 5, 15, 20, or 25 minutes, and / or up to 150 minutes at 60°C. Additionally or alternatively, the hot melt adhesive may exhibit a holding power of at least 400, 600, 800, or 1,000 minutes at 50°C. Holding power at 50°C and 60°C may be measured by stabilizing the glued carton substrates overnight at room temperature (typically 20-23°C) and then suspending the substrates in a shear bank oven in peel mode. A weight is then suspended below the glued substrates. The time at which the weight drops due to failure is recorded for each specimen.

[0187] In an embodiment, or in combination with any embodiment mentioned herein, the hot melt adhesive composition may exhibit a shear adhesion failure temperature ("SAFT"), when measured according to ASTM D4498-07, of at least 75, 80, 85, 90, 95, 100, 110, 120, 130, or 135°C. Additionally or alternatively, the hot melt adhesive composition may exhibit a shear adhesion failure temperature ("SAFT"), when measured according to ASTM D4498-07, of not more than 200, 160, 155, 150, 140, 135, 134, 133, 130, or 135°C. For example, the hot melt adhesive may exhibit a SAFT in the ranges of 2 to 200, 50 to 150, 75 to 125, 130 to 160, 130 to 155, 130 to 150, 130 to 145, 135 to 155, 135 to 150, 140 to 160, 140 to 155, 140 to 150, 145 to 160, 145 to 155, or 145 to 150°C when measured according to ASTM D4498-07.

[0188] In certain embodiments, or in combination with any embodiment mentioned herein, the hot melt adhesive composition may exhibit a lap shear of at least 25, 50, 75, or 100, and / or no more than 300, 275, 250, 225, 200, 175, 150, or 125 lbf, when measured according to ASTM D 1002. For example, the hot melt adhesive composition may exhibit a lap shear in the range of 25 to 300, 50 to 275, 75 to 250, 100 to 250, or 100 to 225 lbf, when measured according to ASTM D 1002.

[0189] In certain embodiments, or in combination with any embodiment mentioned herein, the hot melt adhesive composition may exhibit a high temperature performance fiber tear ("HTFT") of at least 50, 65, 70, 75, 80, 85, 90, or 95 percent at 60°C. The HTFT test consists of manually tearing a glued corrugated paper (carton) substrate by hand at 60°C. The glued carton substrate must be stabilized at 60°C for 4 hours ± 5 minutes before tearing. If 80% of the substrate breaks, the test is considered to be passed, and therefore the hot melt adhesive is considered to perform well. In some applications, if 50% of the fibers in the substrate break, the test is considered to be passed, and the adhesive is considered to perform well at 60°C.

[0190] In certain embodiments, or in combination with any embodiment mentioned herein, the hot melt adhesive composition may exhibit a Ring and Ball softening point, as measured by ASTM Method E-28, of at least 100, 105, 110, 115, 120, 125, or 130° C., and / or no greater than 200, 190, 180, 170, 160, 150, or 140° C. For example, the hot melt adhesive composition may exhibit a Ring and Ball softening point, as measured by ASTM Method E-28, of 100 to 200° C., 110 to 180° C., 125 to 160° C., or 130 to 150° C.

[0191] In certain embodiments, or in combination with any embodiment mentioned herein, the hot melt adhesive composition may exhibit a heat resistance of at least 80, 85, 90, 95, or 100° C., and / or no greater than 200, 175, 150, 140, 130, 125, or 120° C. For example, the hot melt adhesive composition may exhibit a heat resistance of 80-200° C., 90-175° C., 100-140° C., or 100-125° C.

[0192] In some embodiments, or in combination with any embodiment mentioned herein, adhesives containing the copolymers of the present invention do not exhibit substantial color change when subjected to high temperature storage conditions for extended periods of time. Before any storage-related aging occurs, the adhesive may have an initial Gardner color, as measured according to ASTM D1544, of less than 18, 15, 10, 8, 5, 4, 3, 2, or 1. After heat aging at 177°C for about 96 hours, the adhesive may exhibit a final Gardner color, as measured according to ASTM D1544, of less than 18, 15, 10, 7, 5, 3, 2, or 1. Thus, the adhesive may retain a desirable color even after extended storage and exposure.

[0193] Exemplary adhesive formulations for use in various applications and on various substrates are set forth below in Table 2. Additionally, Table 2 provides broad, intermediate, and narrow ranges for various properties of the adhesive formulations, which may be combined in any combination regardless of their category (e.g., one or more broad ranges may be combined with one or more intermediate and / or narrow ranges). Further, although broad, intermediate, and narrow ranges are provided in Table 2, it is contemplated that any of the above ranges regarding the adhesive formulation's composition (e.g., polymer content, tackifier content, etc.) and related performance characteristics may be applicable to the adhesive formulations provided in Table 2, so long as such combination does not result in a contradiction.

[0194] [Table 5]

[0195] In some embodiments, or in combination with any of the embodiments mentioned herein, the propylene-ethylene copolymers of the present invention can be utilized in adhesive compositions as described above in this disclosure. In particular, the propylene-ethylene copolymers of the present invention can be utilized to produce hot melt adhesives with a wide process window and high peel strength for laminating materials, such as, but not limited to, sanitary adhesives.

[0196] As mentioned above, the adhesive compositions described herein may be used to bond a variety of substrates and adherends, thereby forming multi-layer laminates. For example, an article may be produced using the adhesive composition by (a) applying the adhesive composition to at least a portion of a substrate surface, and (b) contacting the treated surface with another surface, thereby forming a laminate.

[0197] The adhesive composition can be used to produce a variety of articles. Exemplary articles that can be produced using the adhesive composition described herein include adhesives, sealants, caulking materials, roofing membranes, waterproofing membranes and underlayments, carpets, laminates, laminate articles, tapes, labels, mastics, polymer blends, wire coatings, molded articles, heat seal coatings, disposable hygiene articles, insulating glass (IG) units, bridge decks, electronic enclosures, waterproofing membranes, waterproofing compounds, underlayments, cable flooding / filling compounds, sheet molding compounds, dough molding compounds, overmolding compounds, rubber compounds, polyester composites, glass composites, glass fiber reinforced plastics, wood plastic composites, polyacrylic blend compounds, lost wax precision casting, investment casting wax compositions, bookbinding, candles, windows, tires, films, gaskets, seals, O-rings, motor vehicles, automobiles, motorcycles, buses and streetcars, trucks, automotive molded parts, automotive extrusion parts, clothing, rubber additives / processing aids, and fibers.

[0198] Exemplary adhesives that can be produced using the adhesive compositions described herein include packaging adhesives, food contact grade adhesives, indirect food contact packaging adhesives, product assembly adhesives, woodworking adhesives, edge banding adhesives, profile wrapping adhesives, flooring adhesives, automotive assembly adhesives, structural adhesives, flexible laminating adhesives, rigid laminating adhesives, flexible film adhesives, flexible packaging adhesives, household repair adhesives, industrial adhesives, building adhesives, furniture adhesives, mattress adhesives, pressure sensitive adhesives (PSA), PSA tapes, PSA labels, PSA protective films, cling films, laminating adhesives, flexible packaging adhesives, heat seal adhesives, industrial adhesives, sanitary nonwoven construction adhesives, sanitary core integrity adhesives, and sanitary elastic attachment adhesives.

[0199] The present invention can be further illustrated by the following examples of this embodiment, although it will be understood that these examples are included for illustrative purposes only and are not intended to limit the scope of the invention unless specifically stated. [Example]

[0200] Example 1 - High Viscosity Propylene-Ethylene Copolymers with High and Medium Tensile Strength A variety of inventive propylene-ethylene copolymers having high viscosity and exhibiting intermediate tensile strength were produced according to the following polymerization process.

[0201] The reactants propylene, ethylene, and hydrogen, along with diluent, external donor, and catalyst, were fed to a 5-gallon continuously stirred tank reactor (CSTR) at the ratios, flow rates, and temperatures provided in Table 3 below for each of the samples produced. The inventive and comparative samples (i.e., the comparative samples produced) were made using a third-generation (Benozate) catalyst and an alkoxysilane as the external electron donor as described above. The reactor was operated at pressures ranging from 790 to 850 psi. Additionally, a hot oil system provided tracing for the reactor jacket. A dip tube conveyed product from the reactor, and an equilibar (pressurized with helium) maintained pressure control of the reactor.

[0202] The copolymer from the letdown tank was then stripped of diluent, and the residual catalyst was then deactivated in a hot oil-jacketed exchanger using steam and nitrogen. The molten copolymer was then collected from the bottom of the deactivator and pumped to a final product collection tank. The resulting inventive copolymers (i.e., samples beginning with a number, e.g., "1A") and comparative copolymers (i.e., samples beginning with a "C," e.g., "C1") were produced according to the reaction conditions listed in Table 3.

[0203] [Table 6]

[0204] The copolymers of the present invention and comparative samples produced under the conditions shown in Table 3 were subjected to testing to verify the properties and characteristics of the copolymers. Unless otherwise specified, various properties were tested using the test methods described.

[0205] Ethylene content and triad tacticity Techniques for determining ethylene and propylene ("PP") composition and triad tacticity by NMR were performed according to the techniques outlined in the aforementioned references. More specifically, samples were prepared by adding 0.4 g of copolymer sample and 100 mg of Cr(acac)3 to a 4-dram vial, followed by the addition of 0.5 mL of ortho-dichlorobenzene-d4 and 3.5 mL of trichlorobenzene (non-deuterated). The resulting solution was magnetically stirred at 120 °C until complete dissolution of the copolymer was observed by visual inspection. Dissolution was typically complete within 1 h. A 10 mm NMR tube was warmed to 80 °C. While wearing heat-resistant gloves, the warm solution was poured into a 10 mm NMR tube to a sample height of approximately 4.5–5 cm. The tube was then capped with a push-on cap. It was important to transfer the solution into the NMR tube while it was still warm to prevent solidification before the transfer was complete. Spectra were analyzed using MNova software. After applying a Fourier transform to the FID data, the spectra were phased, baseline corrected, and calculations were performed as described in the references above. The standard deviation of PP% was determined to be 0.7, and the standard deviation of mm% was determined to be 0.3.

[0206] Preparation of tensile strength samples Film samples for tensile testing were prepared using a Carver press. First, 20 grams of molten sample was placed in a 5-inch x 5-inch (137 mm x 137 mm) aluminum square mold frame with a thickness of 1 mm. The sample was then sandwiched between a silicone-coated PET film, release paper, and a metal board and then heated in the Carver press with zero pressure applied. The sample was compression molded at 177°C to 188°C for 12 minutes, after which a pressure of 6000 PSI was applied for 5 seconds and released. The pressure was then increased to 12000 PSI and released again. Finally, a pressure of 18000 PSI was applied and held for 2 minutes. The sample was then removed from the press and quickly transferred from the hot metal plate to a set of room-temperature plates with a 10 kg weight block on top to act as a heat sink. After an 8-minute cooling period, the weight block and metal plate were removed. The films were stored in a controlled temperature and humidity room (25°C, 50% RH) for 24 hours and then cut using a dumbbell-shaped cutter based on ASTM-D412 die C.

[0207] Tensile test Tensile strength and elongation at break were determined at 20 in / min (51 cm / min) according to the procedure described in ASTM D412 (Die C). All tests were performed on an MTS tensile testing machine in a controlled temperature and humidity (CTH) room at 25°C and 50% RH. Tensile strength at break was calculated by dividing the force magnitude at break by the cross-sectional area of the unstrained specimen. Elongation at break was calculated by the recorded elongation distance at break and normalized by the original standard gauge length of 62.5 mm in the tensile grips.

[0208] Table 4 below provides the measured characteristics and properties of the copolymers. In addition, Table 4 also lists the characteristics and properties of two commercially available propylene-ethylene copolymers, labeled "CAC1" and "CAC2." In the table below, "NP" refers to penetration, "SP" refers to ring and ball softening point, "PP" refers to propylene, "TT" refers to triad tacticity, "TSB" refers to tensile strength at break, "EB" refers to elongation at break, and "H" refers to elongation at break. F " refers to the heat of fusion, and "HC " refers to the heat of crystallization.

[0209] [Table 7] TS * The sample was too soft to measure.

[0210] As shown in Table 4, the copolymers of the present invention exhibited desirable tensile strength (TSB) values superior to those of the comparative examples and existing commercial products of similar viscosity. More specifically, as shown above, the propylene / ethylene content, triad tacticity, viscosity, peak T of the copolymers, and the TSB values were also significantly improved. m The tensile strength, heat of fusion, and heat of crystallization were all important properties in producing copolymers that exhibited excellent tensile strength. For example, Table 4 highlights the importance of ethylene content, which can affect the crystallinity and elongation of the copolymer, as well as triad tacticity, which can affect the tensile profile, elongation, crystallinity, and penetration of the resulting copolymer.

[0211] The inventors have observed that ethylene generally intercalates into the copolymer as crystalline defects primarily in the amorphous phase. Thus, higher ethylene typically disrupts the isotactic polypropylene (iPP) average crystalline sequence length and reduces the percent crystallinity of the copolymer. In general, higher strength propylene-ethylene copolymers, such as those shown in Tables 3 and 4, provide higher initial peel strength in adhesives.

[0212] Figure 1 is a chart comparing the propylene content of the copolymers in Table 4 with the resulting tensile strength at break. As shown in Figure 1, the propylene and ethylene content of the copolymers was important in obtaining excellent tensile strength.

[0213] Example 2 - Medium Viscosity Propylene-Ethylene Copolymers with High and Medium Tensile Strength A variety of propylene-ethylene copolymers of the present invention were produced having medium viscosity and exhibiting medium tensile strength. The propylene-ethylene copolymers were produced according to the polymerization method described in Example 1.

[0214] The resulting inventive copolymers (e.g., "2A") and comparative copolymers (e.g., "C6") were produced according to the reaction conditions listed in Table 5. Unless otherwise specified, the copolymers were tested to verify properties and characteristics using the test methods described above.

[0215] [Table 8]

[0216] The copolymers of the present invention (i.e., samples beginning with a number) and comparative samples (i.e., samples beginning with a "C") produced under the conditions shown in Table 5 were subjected to testing to verify the properties and characteristics of the copolymers. Unless otherwise specified, various properties were tested using the test methods described above.

[0217] Table 6 below provides the measured characteristics and properties of the measured copolymer and two commercially available propylene-ethylene copolymers (labeled "CAC3" and "CAC4") having similar viscosities.

[0218] [Table 9]

[0219] As shown in Table 6 above, the copolymers of the present invention exhibited desirable tensile strength, including higher viscosity, superior to existing commercial products. More specifically, as shown above, the propylene / ethylene content, triad tacticity, viscosity, peak T of the copolymers, mThe viscosity, heat of fusion, and heat of crystallization were all important properties in producing copolymers that exhibit excellent tensile strength and elongation at desirable ring and ball softening points. For example, Table 6 highlights the importance of ethylene content, which can affect the crystallinity and elongation of the copolymer, as well as triad tacticity, which can affect the tensile profile, elongation, crystallinity, and penetration of the resulting copolymer. In general, higher strength propylene-ethylene copolymers, such as those shown in Tables 5 and 6, provide higher initial peel strengths in adhesives.

[0220] Figure 2 is a chart comparing the propylene content of the copolymers in Table 6 with the resulting tensile strength at break. As shown in Figure 2, the propylene and ethylene content of the copolymers was important when obtaining superior tensile strength. It is particularly interesting to compare inventive Example 2O and CAC4, which have similar viscosities and propylene contents. Higher polymer molecular weight is known to contribute to higher viscosity and tensile strength. Inventive Example 2O was found to have an unexpectedly high tensile strength (10.4 MPa, 8,133 cP) for its viscosity, which is evident when compared to the value for CAC4 (i.e., 3.8 MPa, 7,570 cP). Without wishing to be bound by theory, similar viscosities indicate similar molecular weights; therefore, the unexpectedly high tensile strength of Inventive Example 2O is likely a result of the inventive combination of propylene content and tacticity (mm%).

[0221] Example 3 - Low Viscosity Propylene-Ethylene Copolymers with High and Medium Tensile Strength Various propylene-ethylene copolymers of the present invention were produced having low viscosity and exhibiting intermediate tensile strength. The propylene-ethylene copolymers were produced according to the polymerization method described in Example 1.

[0222] The resulting inventive copolymers (eg, "3A") and comparative copolymers (eg, "C11") were produced according to the reaction conditions listed in Table 7 below.

[0223] [Table 10]

[0224] The copolymers of the present invention (i.e., samples prefixed with a number) and comparative samples (i.e., samples prefixed with a "C") produced under the conditions shown in Table 7 were subjected to testing to verify the properties and characteristics of the copolymers. Unless otherwise specified, various properties were tested using the test methods described above. Table 8 below provides the measured properties and characteristics of the copolymers. In addition, Table 8 also lists the properties and characteristics of commercially available propylene-ethylene copolymers listed as "CAC5," "CAC6," "CAC7," "CAC8," and "CAC9."

[0225] [Table 11]

[0226] As shown in Table 8, the copolymers of the present invention had low viscosity and exhibited desirable tensile strength superior to existing commercial products. More specifically, as shown above, the propylene / ethylene content, triad tacticity, viscosity, peak T of the copolymers were also significantly affected. m The tensile strength, heat of fusion, and heat of crystallization were all important properties in producing copolymers that exhibited excellent tensile strength. For example, Table 8 highlights the importance of ethylene content, which can affect the crystallinity and elongation of the copolymer, as well as triad tacticity, which can affect the tensile profile, elongation, crystallinity, and penetration of the resulting copolymer.

[0227] Figure 3 is a chart comparing the propylene content of the copolymers in Table 6 with the resulting tensile strength at break. As shown in Figure 3, the propylene and ethylene content of the copolymers was important when obtaining superior tensile strength. It is particularly interesting to compare inventive Examples 3E and 3F with CAC5. Inventive Examples 3E and 3F have tensile strengths (4.2 MPa and 5.0 MPa, respectively) that are approximately twice as high as CAC5 (2.4 MPa), yet the three copolymers have similar viscosities and propylene contents. While not wishing to be bound by theory, similar viscosities indicate similar molecular weights; therefore, the unexpectedly high tensile strengths of inventive Examples 3E and 3F are likely a result of the inventive combination of propylene content and tacticity (mm%).

[0228] Figure 4 is a chart comparing the tensile strength of all high tensile strength and medium tensile strength inventive copolymers with the viscosity of the corresponding copolymer. The copolymers in Figure 4 include those from Examples 1-3, along with the comparative copolymers and commercial copolymer (CAC) described above. As shown in Figure 4, the viscosity of the inventive copolymers positively affected the tensile strength of the resulting copolymers.

[0229] Example 4 - Woodworking Adhesive To test the copolymers of the present invention, various hot melt adhesives for woodworking applications were produced. Inventive copolymers 1B, 1C, 1D, and 2N were used to produce woodworking adhesives having the formulations provided in Table 16. Additionally, for comparison, adhesive formulations were also produced using Arafin™ 180 from Eastman and Vestoplast® 828 from Evonik Industries. Vestoplast® 828 has a viscosity of 25,000 cP at 190°C, a needle penetration of 22 dmm, a softening point of 161°C, a Tm of 159°C, a tensile strength at break of 0.9 MPa, an elongation at break of 468%, and a heat of crystallization of 8.3 J / g. The adhesive also contained an antioxidant (Irganox® 1076 from BASF), a tackifier (Eastotac™ H100R from Eastman), and a wax (Epolene® E-43 from Westlake Chemical). All of the following amounts in Table 9 for the listed components are provided as weight percentages based on the total weight of the adhesive. The amount of antioxidant added was based on the total weight of the other components.

[0230] The adhesive was made based on the following process: First, the heating block was preheated to approximately 180°C. Next, the copolymer, wax, resin, and antioxidant were weighed and placed into a 1-pint aluminum container. The container was then placed into the heating block. Once the mixture showed signs of melting, a stir bar was inserted and mixed at a speed of approximately 50 rpm until uniform. Once the mixture was homogenous, the stirring speed was increased to 150 rpm for 30 minutes. The speed was then reduced to approximately 30 rpm and mixed for an additional 15 minutes, after which it was removed to remove any air bubbles. The heating block temperature was maintained at approximately 180°C throughout the blending process. The adhesive was poured onto silicon-coated release paper and allowed to cool to room temperature.

[0231] Table 9 provides the formulation and property characteristics of the comparative woodworking adhesive ("CA") and the adhesive of the present invention ("IA").

[0232] [Table 12]

[0233] Adhesive viscosity measurement Viscosity was measured using a Brookfield DV2 Textra viscometer equipped with a Thermosel™ and a number 27 spindle according to internal method in accordance with ASTM D-3236. 10.5 grams of adhesive was placed in a Brookfield tube, and the sample was heated to temperature (if not already melted) for 10 minutes. The sample was then allowed to equilibrate under shear at each respective test temperature for 20 minutes. The spindle rpm was adjusted to maximize motor % with no adjustments made during the final 20 minutes of the shear equilibration period. Values are reported in centipoise (cP). Viscosity readings were taken from the cold to the hot temperature.

[0234] Adhesive ring and ball softening point (RBSP) Adhesive ring and ball softening points were measured using a Herzog Ring and Ball Softening Point Apparatus according to ASTM Method E-28. The formulated adhesive was decanted onto a brass ring and allowed to cool overnight or for 16 hours or more. Samples were trimmed flat before testing. The silicone oil was heated at 5°C per minute until the ball passed through the softened specimen, at which point the temperature was measured. The reported value is the average of two readings.

[0235] Shear Adhesion Failure Temperature (SAFT) - Woodworking Sample Preparation: Two birch substrates (1" x 1") in size were glued together. The adhesive was melted at 180-200°C for at least 20 minutes and then applied to one surface of the birch substrate with a laboratory spatula. Another birch substrate was immediately placed on top of the adhesive, and gentle pressure was applied to ensure a 1" x 1" bond area. A 100g weight was placed on top of the bond area at 350°C for 30 seconds. The final adhesive thickness was 1.5-2.0 mils.

[0236] SAFT temperature measurements followed ASTM D4498-07, "Standard Test Method for Heat-Fail Temperature in Shear of Hot Melt Adhesives." After conditioning at room temperature for at least 24 hours, the specimens were placed in a programmable oven equipped with a Cheminstruments 30-Bank testing machine (West Chester Township, OH). The static load was 500 g. The heating program was set to run from 20°C to 150°C at a ramp rate of 0.5°C / min. The program recorded the time at which the bond failed (the weight dropped) and converted it to the bond failure temperature. A total of three specimens were tested, and the average was reported. The standard deviation was 6°C.

[0237] Lap Shear Strength Test - Woodworking Two birch panels were bonded together using an Adhesive Testing Unit manufactured by ITW Dynatec GmbH (Mettmann, Germany) with a 3±0.9 g / m² adhesive bead applied at 190°C. Prior to testing, specimens were conditioned for 24 hours in a temperature and humidity controlled (CTH) room at 25°C and 50% RH. Strength was measured on an MTS Criterion Model 43 Electromechanical Universal Test System at a speed of 12.7 mm / min. A minimum of five specimens per specimen were tested, and the average value was reported. Testing was performed in accordance with ASTM D1002.

[0238] Heat resistance-woodworking Heat resistance was measured using a 1" x 8" MDF board and a laminated paper substrate bonded with approximately 5 mils of adhesive that was pressed at 350°C for 1.5 minutes. The laminate was mounted horizontally in an oven, and a 10g weight was hung from the edge of the paper laminate. The oven was set to 50°C, and the temperature was increased by 10°C per hour up to a maximum of 150°C. The failure temperature was the temperature at which the paper peeled more than 7 cm from the MDF board. The average of three measurements was reported.

[0239] As shown in Table 9, all of the inventive adhesives exhibited heat resistance above 100°C. In contrast, CA1 only had a heat resistance of 95°C. Additionally, inventive adhesive 4 exhibited an unexpected 114% increase in lap shear strength over the comparative adhesive, while also resulting in a decrease in viscosity. Most surprisingly, the enhanced heat resistance and lap shear of the inventive adhesives was accompanied by a decreased SAFT temperature.

[0240] Example 5 - Woodworking Adhesive To test the copolymers of the present invention, various hot melt adhesives for woodworking applications were produced. Inventive copolymers 1B, 1C, 1D, and 2N were used to produce woodworking adhesives having the formulations provided in Table 10 below. Additionally, for comparison, adhesive formulations were also produced using Arafin™ 180 from Eastman and Vestoplast® 828 from Evonik Industries. The adhesives also contained an antioxidant (Irganox™ 1076 from BASF) and a tackifier (Eastotac™ H130R from Eastman). The adhesives were produced and tested according to the procedure described above in Example 4. All of the following amounts in Table 10 for the listed components are provided as weight percentages based on the total weight of the adhesive. The amount of antioxidant added was based on the total weight of the other ingredients. Table 10 provides the formulations and property characteristics of the comparative woodworking adhesive ("CA") and the inventive adhesive ("IA").

[0241] [Table 13]

[0242] All of the inventive adhesives exhibited desirable lap shear relative to the comparative adhesives, as shown in Table 10. Additionally, the inventive adhesives exhibited lower RBSP, which allows for faster melting and easier processing.

[0243] Example 6 - Hygienic Adhesive with High Viscosity Propylene-Ethylene Copolymer Various hot melt adhesives for sanitary applications were produced to test the copolymers of the present invention (i.e., 1A and 1I from Example 1) having high viscosity. Additionally, adhesive formulations were also produced using Araffin™ 180 from Eastman for comparison. The adhesives also contained an antioxidant (Irganox® 1010 from BASF), a tackifier (Eastotac™ H100R or Regalite™ R1090 from Eastman), a wax (Sasolwax® H-1 from Sasol), and a processing oil (Kaydol Oil from Chevron or Sation 1820 from Sasol). Unless otherwise specified, the adhesives were produced and tested according to the procedure described in Example 4. All of the following amounts in Table 11 for the listed components are provided as weight percentages based on the total weight of the adhesive. The amount of antioxidant added was based on the total weight of the other components. Table 11 provides the formulation and property characteristics of a comparative hygiene adhesive ("CA") and an adhesive of the present invention ("IA").

[0244] [Table 14]

[0245] Nonwoven fabric laminate peel strength (T-peel) measurement A polyethylene ("PE") backsheet manufactured by Berry Global, having a thickness of 1 mil (24.4 gsm), and a hydrophobic nonwoven sheet manufactured by Midwest Filtration, having a thickness of 15 gsm, were bonded together using a Catbridge high-speed coater as described below to form a laminate specimen by applying a hot-melt adhesive between the two sheets at 3 gsm via a Signature nozzle head at 130-160°C. The PE backsheet and hydrophobic nonwoven sheet were peeled from each other at a 180-degree angle and a speed of 300 mm / min using an Instron 3365 tensile strength tester. Except for the instantaneous peel strength, the laminates were conditioned at 25°C and 50% relative humidity after the hot-melt adhesive was applied and before the peel test. The following T-peel test was performed: Instantaneous peel strength - g / 25 mm Peel strength - g / 25 mm, 24 hours Peel strength - g / 25 mm, 38°C, 4 hours Peel strength - g / 25 mm, 55°C, 2 weeks, Peel strength - g / 25 mm, 25°C, 1 month.

[0246] The PE backsheet and hydrophobic nonwoven sheet were pulled 6.5 inches apart and the force recorded as the T-peel strength of the hot melt adhesive. Five replicate specimens were run for each test and the mean / standard deviation was recorded.

[0247] Additionally, the adhesives shown in Table 11 were subjected to further Catbridge trials to analyze the effect of oil content on the peel strength of the adhesive.

[0248] Catbridge calibration and execution process The Catbridge high-speed coater (PL 59188) was manufactured by Catbridge Machinery and equipped with an Acumeter / pump and a Nordson applicator with a Signature nozzle. The Acumeter pump speed was calibrated based on three pump ratios controlled by the Catbridge: 20%, 30%, and 50%. Using a timer, the adhesive was dispensed onto a tared release liner for 1 minute and weighed. The weight was used to plot a graph of weight versus pump speed. An R of greater than 0.98 was obtained. 2 An equation with the formula: was acceptable and gave a slope and constant. The amount of adhesive dispensed as a function of line speed, add weight, and pattern width was determined using the formula: Adhesive amount (g / min) = Line speed (m / min) x Addition weight (g / m 2 ) x pattern width (m)

[0249] Using the slope and constant from the calibration, the pump ratio (%) and pump speed rpm were determined for the amount of adhesive needed. The Catbridge was then run at the required pump speed by adjusting the air pressure to achieve a good adhesive pattern and good edge control. The adhesive was sprayed onto the PE backsheet and combined with the nonwoven fabric using a nip roll set at 30 psi. The line took a few seconds to stabilize, so the line was run for approximately 30-40 seconds to obtain a good, representative sample. If the pattern was not good enough, i.e., there was not enough entanglement or fiberization when viewed under UV light, the air pressure was gradually adjusted until a good pattern was achieved. Typically, higher line speeds or higher viscosity adhesives required higher air pressures.

[0250] The results of the Catbridge trials for IA8, IA9, CA5, IA10, and IA12 are shown in Figure 5, which shows the instantaneous peel strength and the peel strength at 24 hours, 4 hours (aged at 38°C), 2 weeks (aged at 55°C), and 1 month (aged at 25°C).

[0251] As shown in Table 11 above, polymer loadings of 32 to 35 weight percent with a single copolymer type provided an adhesive viscosity range for spraying. Furthermore, as shown in Table 11 and Figure 5, adhesives with lower oil content were able to maintain higher peel strengths, which was aided by the tensile strength of the inventive copolymer. Furthermore, adhesives formed from inventive copolymer 1A exhibited the best overall performance of all adhesives. In particular, it was found that high viscosity copolymers could be used as the sole polymer in adhesive formulations with desirable RBSP, desirable viscosity at spray temperatures of about 130°C to about 160°C, desirable nonwoven / PE instantaneous peel strength, and stable or increasing peel strengths at 24 hours, 4 hours (aging at 38°C), 2 weeks (aging at 55°C), and 1 month (aging at 25°C). A particular adhesive may contain 30 to 45 weight percent propylene-ethylene copolymer, 35 to 55 weight percent of at least one tackifier, 5 to 25 weight percent processing oil, and 0 to 15 weight percent of at least one wax.

[0252] Thus, it has been discovered that an appropriate range of propylene / ethylene comonomer content, along with a particular level of propylene tacticity, provides propylene-ethylene copolymers with a unique balance of moderate tensile strength, viscosity, penetration, and elongation properties that are particularly advantageous for sanitary adhesive applications. More specifically, it has been observed that the tensile strength of the copolymers of the present invention is high enough to contribute to adhesive bond strength in formulated adhesives, but not so high that bond strength is significantly lost after aging. Furthermore, by maintaining a particular triad tacticity in the copolymers of the present invention, the tensile strength, elongation, crystallinity, and penetration of the resulting copolymers can form adhesives that exhibit excellent aging properties.

[0253] Example 7 - Sanitary Adhesive with Medium Viscosity Propylene-Ethylene Copolymer To test the inventive copolymer from Example 2 with a medium viscosity, various hot melt adhesives for sanitary applications were produced. Additionally, for comparison, adhesive formulations were also produced using comparative copolymers C8 and C9. The adhesives also contained an antioxidant (Irganox® 1010 from BASF), a tackifier (Eastotac® H100R or Regalite® R1090 from Eastman), a wax (Sasolwax® H-1 from Sasol), possibly an additional propylene-ethylene copolymer (Eastflex® E1003 from Eastman), and a processing oil (Kaydol Oil from Chevron). Additionally, inventive adhesives IA20 and IA21 contained a small amount of one additional high-viscosity copolymer, namely, Kraton D1657 SEBS styrene block copolymer from Kraton and INFUSE® 9807 olefin block copolymer from Dow, respectively.

[0254] Adhesives were produced and tested according to the procedures described in Examples 4 and 6. All of the following amounts in Tables 12 and 13 for the listed components are provided in weight percent based on the total weight of the adhesive. Table 12 below provides the formulation and property characteristics of a comparative hygiene adhesive ("CA") and an inventive adhesive with high oil content ("IA"), while Table 13 below provides the formulation and property characteristics of a comparative hygiene adhesive ("CA") and an inventive adhesive with low oil content ("IA").

[0255] [Table 15]

[0256] [Table 16]

[0257] The adhesives shown in Tables 12 and 13 were subjected to Catbridge tests to analyze the effect of oil content on the peel strength of the adhesives. The results of the Catbridge tests for CA6, IA9, IA20, IA21, C10, IA23, IA24, and IA26 are shown in Figure 6, which shows the instantaneous peel strength and the peel strength at 24 hours, 4 hours (38°C), 2 weeks (55°C), and 1 month (25°C).

[0258] Generally, medium viscosity olefin copolymers are not used as the sole polymer in producing adhesives because their cohesive strength is not good enough. However, as shown in Tables 12 and 13 above, the copolymers of the present invention having medium viscosity were able to produce desirable adhesives both as the only polymer in the adhesive and as the predominant polymer present in the adhesive. Additionally, the adhesive formulations of the present invention had desirable RBSP and viscosity, could be successfully sprayed at 150°C, and could exhibit stable or increased peel strength after aging for 24 hours, 4 hours (38°C), 2 weeks (55°C), and 1 month (25°C). Generally, to obtain higher polymer loadings (e.g., 50 weight percent), higher loadings of oil were required to meet the viscosity required for adhesive spraying.

[0259] It was also observed that using Eastoflex™ E1003 to replace a portion of the processing oil did not provide any benefit. Rather, it significantly increased the adhesive's viscosity, thereby reducing the propylene-ethylene copolymer content and adversely affecting peel strength. It was also observed that adding higher viscosity copolymers, such as IA20 and IA21, allowed the adhesive to maintain its peel strength and tolerate greater amounts of processing oil. Generally, to use less processing oil, the copolymer content had to be reduced, as in IA23, IA24, and IA25. Consequently, in some cases, this resulted in increased peel strength. For example, as shown in Table 13, IA23 and IA24 exhibited higher peel strength compared to CA7. However, the peel strength of IA25 decreased by 60% the next day, and the adhesive was hard, so it could not complete the aging test. IA24 also exhibited a softer feel, which may be desirable for hygienic applications.

[0260] As shown in Tables 12 and 13 and Figure 6, there are advantages to using a medium viscosity copolymer over a low viscosity copolymer, as the medium viscosity copolymers of the present invention have better tensile properties and therefore may require less (or no) additional polymer to add strength. Furthermore, it has been demonstrated that medium tensile strength polymers, such as 2A, are well suited as the sole polymer in sanitary adhesives, as they can provide excellent peel strength both immediately and after aging.

[0261] Example 8 - Comparison of adhesives of the present invention with commercially available adhesives Inventive adhesive IA10 from Example 6, inventive adhesive IA23 from Example 7, and inventive adhesive IA24 from Example 7 were compared to existing commercially available adhesives, namely, Safemelt™ DP830H / ST (SBS system) from Savare, 5603N2P (mPO system) from HB Fuller, and Safemelt™ VV25F / SW (butene-APO system) from Savare. The adhesives were tested according to the procedures described in Examples 4 and 6. Table 14 below provides the properties of the inventive adhesives and the commercially available adhesives.

[0262] [Table 17]

[0263] The adhesives shown in Table 14 were subjected to a Catbridge test to analyze and compare the effect of oil content on the peel strength of the adhesive. The results of the Catbridge test are shown in Figure 7, which shows the peel strength at 24 hours, 4 hours (38°C), 2 weeks (55°C), and 1 month (25°C).

[0264] As shown in Table 14 in conjunction with Figure 7, the copolymers of the present invention were suitable as single polymers in producing sanitary adhesives that exhibited excellent peel strength, especially after aging. Furthermore, the peel strength performance of the adhesives of the present invention was comparable to commercial adhesives currently on the market. Furthermore, the adhesives of the present invention sprayed very well and did not require high air pressure to achieve a good pattern. In contrast, commercial butene-APO-based adhesives did not spray well at low temperatures and required high air pressure to achieve a good pattern. Additionally, the adhesives of the present invention exhibited sufficient cohesive strength to operate on high-speed lines up to 600 m / min.

[0265] Considering the above, it was observed that there is a direct correlation between the mechanical properties of the propylene-ethylene copolymer and the peel strength of the adhesive. However, too high a tensile strength was observed, causing a decrease in peel strength upon aging.

[0266] definition It should be understood that the following is not intended to be an exhaustive list of defined terms. Other definitions may be provided in the preceding description, for example, as they accompany the use of a defined term in context.

[0267] As used herein, the terms "a," "an," and "the" mean one or more.

[0268] As used herein, the term "about" refers to any value within a range of 90% to 110% of the specified value. However, it should be noted that all values associated with "about" include support for the specific value itself and the range associated with the "about" specific value. For example, "about 10" provides support for the specific value of "10" and a range of values from 9 to 11. Furthermore, the term "about" can be associated with any specific value listed herein.

[0269] As used herein, the term "and / or," when used in a list of two or more items, means that any one of the listed items can be used alone, or any combination of two or more of the listed items can be used. For example, if a composition is described as containing components A, B, and / or C, the composition can contain A only, B only, C only, a combination of A and B, a combination of A and C, a combination of B and C, or a combination of A, B, and C.

[0270] As used herein, the phrase "at least a portion" includes at least a portion and up to the entire amount or period.

[0271] As used herein, the terms "comprising," "comprises," and "comprise" are open-ended transitional terms used to transition from the subject matter described before the term to one or more elements described after the term, and the element or elements listed after the transitional term are not necessarily the only elements that make up the subject matter.

[0272] As used herein, the terms "having," "has," and "have" have the same open-ended meaning as "comprising," "comprises," and "comprise" provided above.

[0273] As used herein, the terms "including," "include," and "included" have the same open-ended meaning as "comprising," "comprises," and "comprise" provided above.

[0274] Numeric range When a numerical sequence is presented, each number should be understood to be modified in the same manner as the first or last number in the sequence or sentence. For example, each number may be "at least" or "less than or equal to," as the case may be, and each number is in an "or" relationship. In an exemplary scenario, "at least 10, 20, 30, 40, 50, 75 weight percent..." means the same as "at least 10 weight percent, or at least 20 weight percent, or at least 30 weight percent, or at least 40 weight percent, or at least 50 weight percent, or at least 75 weight percent."

[0275] This description uses numerical ranges to quantify certain parameters related to the present invention. When numerical ranges are provided, it should be understood that such ranges are to be interpreted as providing literal support for claim limitations that recite only the lower limit of the range, as well as for claim limitations that recite only the upper limit of the range. For example, a disclosed numerical range of 10 to 100 provides literal support for claims that recite "greater than 10" (without an upper limit) and claims that recite "less than 100" (without a lower limit).

[0276] The claims are not limited to the disclosed embodiments. The above-described preferred embodiments of the present invention should be used only as examples and should not be used in a limiting sense to interpret the scope of the present invention. Modifications to the above-described exemplary embodiments can be easily made by those skilled in the art without departing from the spirit of the present invention.

[0277] The inventors hereby express their intention to rely on the doctrine of equivalents to determine and assess the reasonably fair scope of the present invention as it relates to devices that do not materially depart from the literal scope of the invention as set forth in the following claims, but that fall outside that scope. Furthermore, although specific embodiments of the present invention are discussed, the present invention encompasses any combination of those embodiments.

Claims

1. A propylene-ethylene copolymer comprising propylene and ethylene, the propylene-ethylene copolymer comprising: (a) 77 to 90 weight percent propylene; (b) comprising 52% to 75% triad tacticity (mm %); (c) having a Brookfield viscosity of at least 4,000 cP at 190°C; (d) exhibiting a ring and ball softening point of 90 to 135°C; and (e) A propylene-ethylene copolymer exhibiting a tensile strength at break of at least 2.5 MPa.

2. 10. The propylene-ethylene copolymer of claim 1, wherein the propylene-ethylene copolymer comprises 10 to 23 weight percent ethylene.

3. 2. The propylene-ethylene copolymer of claim 1, wherein the triad stereoregularity of the propylene-ethylene copolymer is from 53% to 70%.

4. 2. The propylene-ethylene copolymer of claim 1, wherein the propylene-ethylene copolymer has a Brookfield viscosity at 190° C. of 4,000 to 88,000 cP.

5. 10. The propylene-ethylene copolymer of claim 1, wherein the propylene-ethylene copolymer exhibits a heat of crystallization of 15 to 42 J / g and a heat of fusion of 9 to 33 J / g.

6. 2. The propylene-ethylene copolymer of claim 1, wherein the propylene-ethylene copolymer has a ring and ball softening point of 100 to 135° C. and a penetration of 2 to 24 dmm.

7. 10. The propylene-ethylene copolymer of claim 1, wherein the propylene-ethylene copolymer exhibits an elongation at break of from 100% to 1,000% and a tensile strength at break of from 2.5 to 20 MPa.

8. The propylene-ethylene copolymer has less than 1 weight percent C ４ ~C １０ The propylene-ethylene copolymer of claim 1 comprising an alpha-olefin.

9. The propylene-ethylene copolymer is (i) containing 10 to 23 weight percent ethylene; (ii) having a triad tacticity (mm%) of 53% to 70%; (iii) having a Brookfield viscosity of 4,000 to 88,000 cP at 190°C; (iv) exhibiting a tensile strength at break of 3.5 to 20 MPa; and (v) The propylene-ethylene copolymer of claim 1, exhibiting a penetration of 3 to 23 dmm.

10. A composition comprising the propylene-ethylene copolymer of claim 1.

11. 10. The process for producing a propylene-ethylene copolymer of claim 1, comprising polymerizing ethylene and propylene at a temperature of 160°C or less, said polymerization being carried out in the presence of a catalyst system, said catalyst system having a molar ratio of aluminum to titanium in the range of 1:1 to 100:

1.

12. 10. An article comprising the propylene-ethylene copolymer of claim 1, wherein the article is selected from the group consisting of adhesives, sealants, caulkings, roofing membranes, waterproofing membranes and underlayments, carpets, laminates, laminate articles, tapes, labels, mastics, polymer blends, wire coatings, molded articles, heat seal coatings, disposable hygiene articles, insulating glass (IG) units, bridge decks, electronic enclosures, waterproofing membranes, waterproofing compounds, underlayments, cable flooding / filling compounds, sheet molding compounds, dough molding compounds, overmolding compounds, rubber compounds, polyester composites, glass composites, fiberglass reinforced plastics, wood plastic composites, polyacrylic blend compounds, lost wax investment casting, investment casting wax compositions, bookbinding, candles, windows, tires, films, gaskets, seals, O-rings, automobiles, motorcycles, automotive molded parts, automotive extruded parts, apparel, rubber additives / processing aids, and fibers; 10. The article of claim 1, wherein the adhesive comprises a packaging adhesive, a food contact grade adhesive, an indirect food contact packaging adhesive, a product assembly adhesive, a woodworking adhesive, an edge banding adhesive, a profile wrapping adhesive, a flooring adhesive, an automotive assembly adhesive, a structural adhesive, a flexible laminating adhesive, a rigid laminating adhesive, a flexible film adhesive, a flexible packaging adhesive, a home repair adhesive, an industrial adhesive, a building adhesive, a furniture adhesive, a mattress adhesive, a pressure sensitive adhesive (PSA), a PSA tape, a PSA label, a PSA protective film, a cling film, a laminating adhesive, a flexible packaging adhesive, a heat seal adhesive, an industrial adhesive, a sanitary nonwoven construction adhesive, a sanitary core integrity adhesive, or a sanitary elastic attachment adhesive.

13. A composition comprising a propylene-ethylene copolymer containing propylene and ethylene, said composition comprising: (a) 5 to 100 weight percent of a propylene-ethylene copolymer; (i) 77 to 90 weight percent propylene; (ii) comprising a triad tacticity (mm%) of 52% to 75%; (iii) having a Brookfield viscosity of at least 4,000 cP at 190°C; (iv) exhibiting a ring and ball softening point of 90 to 135°C; and (v) a propylene-ethylene copolymer exhibiting a tensile strength at break of at least 2.5 MPa; (b) 0 to 55 weight percent of at least one second polymer; (c) up to 70 weight percent of at least one tackifier; (d) 20 weight percent or less of a processing oil; (e) 35 weight percent or less of at least one wax.

14. The composition of claim 13, wherein the propylene-ethylene copolymer comprises 10 to 23 weight percent ethylene.

15. 14. The composition of claim 13, wherein the propylene-ethylene copolymer has a triad tacticity of 55% to 65%.

16. 14. The composition of claim 13, wherein the propylene-ethylene copolymer has a Brookfield viscosity of 4,000 to 88,000 cP at 190°C.

17. 14. The composition of claim 13, wherein the propylene-ethylene copolymer exhibits a heat of crystallization of 15 to 42 J / g and a heat of fusion of 9 to 33 J / g.

18. 14. The composition of claim 13, wherein the propylene-ethylene copolymer exhibits a ring and ball softening point of 100 to 135°C and a needle penetration of 2 to 24 dmm.

19. 14. The composition of claim 13, wherein the propylene-ethylene copolymer exhibits an elongation at break of from 100% to 1,000% and a tensile strength at break of from 2.5 to 20 MPa.

20. The composition of claim 13, wherein the composition comprises 20 to 80 weight percent of the propylene-ethylene copolymer.

21. The composition comprises: (a) 25 to 45 weight percent of a propylene-ethylene copolymer; (b) 0 to 15 weight percent of a second polymer; (c) 45 to 50 weight percent of a tackifier; (d) 0 to 15 weight percent processing oil; (e) 0 to 10 weight percent of a wax.

22. 14. The composition of claim 13 having a Brookfield viscosity in the range of 500 to 20,000 cP at 190°C.

23. 14. An article comprising the composition of claim 13, wherein the article is selected from the group consisting of adhesives, sealants, caulkings, roofing membranes, waterproofing membranes and underlayments, carpets, laminates, laminate articles, tapes, labels, mastics, polymer blends, wire coatings, molded articles, heat seal coatings, disposable hygiene articles, insulating glass (IG) units, bridge decks, electronic enclosures, waterproofing membranes, waterproofing compounds, underlayments, cable flooding / filling compounds, sheet molding compounds, dough molding compounds, overmolding compounds, rubber compounds, polyester composites, glass composites, fiberglass reinforced plastics, wood plastic composites, polyacrylic blend compounds, lost wax investment casting, investment casting wax compositions, bookbinding, candles, windows, tires, films, gaskets, seals, O-rings, automobiles, motorcycles, automotive molded parts, automotive extruded parts, apparel, rubber additives / processing aids, and fibers; 1. The article, wherein the article is an adhesive, and the adhesive comprises a packaging adhesive, a food contact grade adhesive, an indirect food contact packaging adhesive, a product assembly adhesive, a woodworking adhesive, an edge banding adhesive, a profile wrapping adhesive, a flooring adhesive, an automotive assembly adhesive, a structural adhesive, a flexible laminating adhesive, a rigid laminating adhesive, a flexible film adhesive, a flexible packaging adhesive, a home repair adhesive, an industrial adhesive, a building adhesive, a furniture adhesive, a mattress adhesive, a pressure sensitive adhesive (PSA), a PSA tape, a PSA label, a PSA protective film, a cling film, a laminating adhesive, a flexible packaging adhesive, a heat seal adhesive, an industrial adhesive, a sanitary nonwoven construction adhesive, a sanitary core integrity adhesive, or a sanitary elastic attachment adhesive.

Images