Crosslinked styrenic block copolymer

Abstract

Elastomer-based styrene-type block copolymer (SBC) compositions are provided. The compositions comprise one or more SBCs and one or more polymers miscible with the styrene-type end blocks of the one or more SBCs. The block copolymer compositions are physically crosslinked and chemically crosslinked, wherein the chemical crosslinking includes covalent bonds between the chains of the SBCs, and the physical crosslinking includes non-covalent interactions between the styrene-type end blocks of the one or more SBCs and the one or more polymers miscible with the styrene-type end blocks. The block copolymer compositions can be used to form impregnated articles such as surgical gloves.

Description

[0001] This application is a divisional application of the invention patent application No. 201880049471.8 entitled "Crosslinked Styrene Block Copolymer", filed on May 28, 2018. Technical Field

[0002] This disclosure relates to physically and chemically crosslinked styrene-type block copolymers. These copolymers have advantageous uses in the manufacture of elastically impregnated articles such as gloves and condoms. Background Technology

[0003] Thin-walled elastic impregnated articles are traditionally made of natural rubber (NR), polychloroprene (CR), polyisoprene (IR), polyurethane (PU), nitrile rubber (NBR), styrene-type block copolymers (SBC), mixtures thereof, or laminates thereof.

[0004] Natural rubber is used in such applications because it is a natural product that provides superior performance. However, the presence of sensitizing proteins that cause immediate-type hypersensitivity reactions (type I hypersensitivity) limits its use. To overcome this drawback, synthetic materials have been developed as alternatives.

[0005] Typical processing

[0006] Thin-walled elastic films are typically formed for intended applications (gloves, condoms, etc.) by immersing a mold of suitable shape into a liquid mixture of polymers, which can be a dispersion (latex) in water or a solution in one or more suitable solvents. A solid film is formed after the water or other solvent evaporates.

[0007] Enhanced mechanical and chemical properties, elasticity, and durability are achieved through cross-linking mechanisms. For most elastomer materials such as NR or IR, vulcanization is the traditional chemical cross-linking mechanism. Vulcanization creates sulfur covalent bonds that link one polymer chain to another. However, because vulcanization with sulfur alone requires excessively long reaction conditions and very high temperatures, chemical additives such as "accelerators" are added. Accelerators can be of various types and are generally classified into the following families: thiazoles, carbamates, guanidines, thioureas, and thiurams. It is common practice to use mixtures of different accelerators selected from different families to optimize vulcanization rate and performance.

[0008] However, while sulfur is covalently integrated into the polymer network, accelerators are not. Typical glove formulations made from polyisoprene may contain up to 2% accelerators. Accelerator molecules are poorly soluble in water and cannot be removed from gloves by washing. Furthermore, due to their limited compatibility with rubber, they may "bloom" on the film surface over time. Accelerators are also strong skin sensitizers and can cause allergic contact dermatitis (delayed-type hypersensitivity, type IV).

[0009] Product Performance

[0010] A specific combination of materials, mixing conditions, and methods for converting into thin-walled membranes often limits the performance of the resulting product.

[0011] NR, CR, IR, and NBR are the more common elastomers, and all begin as aqueous dispersions (also known as lattices) to be transformed into thin-walled films. However, thin-walled films produced by lattices have the disadvantage of sometimes being prone to pinholes in the resulting product. These pinholes, typically on the order of micrometers in diameter, may be caused by low levels of impurities in the latex that are difficult to filter out, and are due to the fact that the method transforms a heterogeneous system (dispersion) into a film. Some inherent microporosity exists in rubber, which may be attributed to the fact that all the latex particles constituting a typical film cannot completely aggregate together to form a gapless, continuous membrane. Natural proteins (present in NR) and chemicals (surfactants, primarily in the case of synthetic polymers) used for latex stabilization and in the manufacturing process readily inhibit aggregation.

[0012] Advantageously, some other synthetic polymers can be dissolved in solvents such as hydrocarbon solvents to form true solutions. Therefore, solvent casting technology is attractive for the production of membranes with extremely high quality requirements and virtually no microporosity. Pinholes are also unlikely to be present.

[0013] Multiblock rubber-based copolymers, especially styrene-based block copolymers (SBCs), are particularly suitable for solvent casting because they can form solutions with acceptable viscosities suitable for impregnation.

[0014] Styrene block copolymers

[0015] SBCs are classified as thermoplastic elastomers, possessing the mechanical properties of rubber and the processing characteristics of thermoplastic materials. These properties arise from their molecular structure. SBCs consist of at least three blocks, typically two rigid polystyrene end blocks and one soft elastomer (polybutadiene, polyisoprene—hydrogenated or unhydrogenated) middle block. More common SBCs include linear triblock copolymers such as styrene-ethylene / butene-styrene (SEBS), styrene-butadiene-styrene (SBS), and styrene-isoprene-styrene (SIS), but other structures (e.g., copolymers composed of more than three blocks) and other structures (star-shaped or star-shaped) are also possible.

[0016] The hard and soft blocks are immiscible, allowing the polystyrene blocks to form individual domains within the rubber matrix at the microscale. Therefore, SBCs exhibit two glass transition temperatures (Tg), which is characteristic of the corresponding homopolymers (e.g., polystyrene end blocks, 90 to 100 °C and rubbery intermediate blocks, around –90 °C, in the case of polybutadiene).

[0017] In addition to the advantages of processing from a true solution, SBC is also able to form an elastic film with high mechanical properties without the use of any chemical crosslinking such as sulfur and accelerators, because each rubber-like block is end-capped by polystyrene segments and these rigid domains act as multifunctional junctions to create a “physically” crosslinked elastomer network, which in many ways resembles conventional vulcanized rubber (“chemically crosslinked”).

[0018] Finally, these elastomers can be advantageously formulated with suitable plasticizers to provide, for example, the desired combination of tensile strength, elasticity, and feel required for surgical gloves.

[0019] Breaking limit force and tensile strength are important factors in evaluating the performance of thin-walled stretchable films such as condoms or gloves, and should be evaluated according to international standards. Furthermore, surgical gloves should provide high sensitivity while not compressing the wearer's hand over extended periods. To prevent hand compression, a modulus of less than 1.0 MPa at 100% elongation is preferred, ideally less than 0.7 MPa.

[0020] SBCs formulated with appropriate plasticizers can meet all international standards and achieve flexibility and mechanical properties comparable to, and in many cases superior to, other elastomers such as NRL, CR, and IR. This means that the material can function mechanically in a manner comparable to or superior to other elastomers, while avoiding the drawbacks of latex-based elastomers, such as accelerators and pinholes.

[0021] In summary, SBC is particularly suitable for thin-walled film applications such as medical gloves, offering superior performance, including: synthetic rubber free of natural rubber proteins, free of accelerators, softness, and extremely high-quality film with virtually no pinholes and no hydration.

[0022] Suitable SBC compositions for use in surgical gloves are described in EP 0 488 021, which discloses a combination of two or more S-EB-S block copolymers, and EP 1 472 315, which discloses a combination of an S-EB-S block copolymer and an S-EP-S-EP block copolymer.

[0023] Limitations of styrene block copolymers

[0024] Products made from the SBCs described in the aforementioned patent have a major drawback. Because the network is formed only by physical cross-linking rather than chemical cross-linking, the glassy polystyrene domains soften and lose their cohesive strength when exposed to certain organic solvents.

[0025] For example, surgical gloves made of SBC can be damaged upon direct contact with organic solvents. Several organic solvents and "corrosive" chemicals are used in the medical field. One example is methyl methacrylate monomer (MMA), which is found in uncured bone cement used in arthroplasty. MMA has a strength of 17.9 MPa. 1 / 2 The Hansen solubility parameter is close to that of PS (18.6). Another example is ether, which is used as a solvent in some formulations such as collodion. The weak chemical resistance to these solvents is a major limitation of this family of elastomers used in gloves for surgical applications.

[0026] Physical networks can be enhanced by incorporating chemical networks that link the chains of the elastomeric phase together via permanent covalent bonds to obtain insoluble materials. One example is described in Decker et al., Journal of Applied Polymer Science (Vol. 77, 1902–1912, 2000), using a commercially available SBS and SIS triblock copolymer crosslinked by UV radiation in the presence of a free radical type photoinitiator. The crosslinking process can be significantly accelerated by incorporating polyfunctional organic molecules such as acrylate or thiol monomers, which can be copolymerized with polybutadiene or polyisoprene unsaturated monomers.

[0027] However, this chemical crosslinking process leads to a significant reduction in the mechanical properties of the membrane, as the coexistence of two networks (one "physical" and one "chemical") reduces the material's resistance to mechanical stress and increases its rigidity.

[0028] For example, such materials do not meet the international standards for surgical gloves, such as the minimum tensile strength specified in ASTM D3577.

[0029] Therefore, it is desirable to provide alternative SBC compositions and methods for their preparation that address one or more of the aforementioned prominent problems and defects.

[0030] References to any existing publications (or information derived therefrom) or any known content in this specification are not and should not be construed as an acknowledgment or endorsement, or any form of implication, that such existing publications (or information derived therefrom) or known content form part of the common general knowledge in the field covered by this specification. Summary of the Invention

[0031] In one aspect, this disclosure provides an elastomeric styrene-type block copolymer (SBC) composition comprising one or more SBCs and one or more polymers miscible with styrene-type end blocks of said one or more SBCs;

[0032] The block copolymer composition is physically crosslinked and chemically crosslinked;

[0033] The chemical crosslinking mentioned above includes covalent bonds between the chains of the SBC; and

[0034] The physical crosslinking includes non-covalent interactions between the styrene-terminated blocks of the one or more SBCs and the one or more polymers miscible with the styrene-terminated blocks.

[0035] On the other hand, this disclosure provides miscible polymer blends comprising one or more SBCs and one or more polymers miscible with styrene-type end blocks of said one or more SBCs.

[0036] The miscible polymer blends described therein are physically cross-linked and chemically cross-linked;

[0037] The chemical crosslinking mentioned above includes covalent bonds between the chains of the SBC; and

[0038] The physical crosslinking includes non-covalent interactions between the styrene-terminated blocks of the one or more SBCs and the one or more polymers miscible with the styrene-terminated blocks.

[0039] The unique compositions or blends disclosed herein, comprising physically and chemically crosslinked styrene block copolymers, can be used, for example, to manufacture thin-walled impregnated items such as condoms and medical gloves. These unique compositions or blends overcome the limitations of currently available SBCs in terms of chemical resistance, while maintaining a high level of mechanical resistance and flexibility.

[0040] In another aspect, this disclosure provides an elastomeric styrene-type block copolymer composition comprising:

[0041] (a) One or more SBCs;

[0042] (b) One or more polymers miscible with the polystyrene-terminated blocks of the one or more SBCs; and

[0043] (c) One or more crosslinking agents capable of causing covalent bonding between the chains of the one or more SBCs.

[0044] In another aspect, a method for preparing an SBC composition is provided, comprising the steps of: combining one or more SBCs, one or more polymers miscible with polystyrene-terminated blocks of the one or more SBCs; and one or more crosslinking agents capable of inducing covalent bonding between the chains of the one or more SBCs.

[0045] The composition or blend may further comprise one or more plasticizers and / or toughening agents compatible with the elastomeric intermediate blocks of the one or more SBCs.

[0046] The composition or blend may further include one or more compatibilizers that enhance the miscibility between the styrene-terminated blocks of the one or more SBCs and the one or more miscible polymers. Such compatibilizers may be, for example, surfactants, particularly polymeric surfactants such as diblock copolymers containing PS segments, or low molecular weight polymers or resins with suitable solubility parameters.

[0047] The one or more SBCs may have fully unsaturated or partially unsaturated elastomeric intermediate blocks, or may have fully saturated elastomeric intermediate blocks.

[0048] The one or more SBCs may be selected from SIS, SBS, SIBS, S-isobutylene-S, SEBS, SEPS, SEEPS, or SBC, and they are functionalized with reactive groups grafted into the intermediate rubber block, such as carboxylic acid groups, amino groups, alcohol groups, maleic anhydride groups, epoxy groups, isocyanate groups, and aziridinyl groups or mixtures thereof.

[0049] Preferably, the SBC consists of one or a mixture of SBCs with a molecular weight (Mn) greater than 100,000 g / mol. Preferably, at least one SBC has an elastomeric interblock containing reactive functional groups, such as double bonds, for example carbon-carbon double bonds, to enable chemical crosslinking.

[0050] Polymers miscible with polystyrene end blocks can be polymers capable of forming close blends with polystyrene end blocks at the molecular level to a certain extent. The miscible polymer can be a polymer miscible with polystyrene, i.e., SBC and the miscible polymer can form homogeneous blends through chemical similarity and / or through specific interactions (such as between π bonds in the aromatic ring). The interactions can be non-covalent. The interactions may not include covalent bonds between the SBC and the miscible polymer.

[0051] Preferably, the number average molecular weight (Mn) of the miscible polymer is less than 10,000 g / mol, more preferably less than 3,000 g / mol.

[0052] Preferably, the miscible polymer has a wide molecular weight polydispersity index, for example, greater than 2.0, or greater than 3.0, or greater than 4.0, or greater than 5.0. The miscible polymer preferably has polarity similar to that of polystyrene.

[0053] In a preferred embodiment, the miscible polymer is selected from low molecular weight copolymers of alkyl aromatic monomers.

[0054] Miscible polymers may be selected from polystyrene resins, coumarone-indene resins, polyindene resins, poly(methylindene) resins, vinyltoluene-α-methylstyrene resins, α-methylstyrene resins, polyphenylene ethers, copolymers of alkyl aromatic monomers such as α-methylstyrene and p-methylstyrene, rosin esters, stylated terpenes, polyterpenes, terpene phenols, and mixtures thereof.

[0055] The crosslinking agent may be selected from aromatic, aliphatic, and heteroaromatic monomers and oligomers containing at least two carbon-carbon double bonds, such as: polyfunctional acrylates, such as trimethylolpropane triacrylate (TMPTA), trimethylolpropane trimethacrylate (TMPTMA), epoxy acrylates, urethane acrylates; triallyl-cyanurate, triallyl-isocyanurate; functional thiols, such as 1,8-dimercapto-3,6-dioxaoctane, trimethylolpropane-tri-3-mercaptopropionate, pentaerythritol tetra-3-mercaptopropionate, ethoxylated trimethylolpropane tri(3-mercaptopropionate); and other polyfunctional compounds having vinyl or allyl groups; and mixtures thereof.

[0056] The crosslinking agent can also be a metal salt; an amine crosslinking agent or a polyol selected from organic amines, organic diamines and organic polyamines.

[0057] Chemical crosslinking can also be carried out through so-called "vulcanization," in which the crosslinking agent can be selected from conventional sulfur, metal oxides, and accelerators, which are commonly used for vulcanizing thin-walled elastic films such as rubber in condoms and gloves. Vulcanization is not considered a preferred crosslinking route in the present invention disclosure because the accelerator, as a strong skin sensitizer, is not integrated into the chemical network and may cause blooming on the surface.

[0058] In a preferred embodiment, the crosslinking reaction is a thiol-ene reaction. The thiol-ene reaction is a so-called "click" reaction, which can occur as a free radical-mediated addition reaction.

[0059] Preferably, the crosslinking agent is selected from, for example, dithiols, trithiols, and tetrathiols whose backbone contains ether or ester groups.

[0060] Advantageously, the cross-linking reaction can be initiated by radiation, such as UV, gamma radiation, X-rays, or electron beam radiation. Radiation offers several advantages: the energy is high enough to generate free radicals from existing chemicals, there is less risk of shielding effects, as can be observed with UV curing, and the technique also provides good and precise control of the dosage. It should also be noted that most surgical gloves are sterilized by radiation (electron beam or gamma radiation), so cross-linking can advantageously occur in the same process as the glove sterilization itself.

[0061] In another embodiment, the crosslinking reaction can be initiated or enhanced by one or a mixture of free radical type photoinitiators.

[0062] When used, the photoinitiator is preferably selected from compounds that provide a broad UV absorption spectrum upon irradiation and effectively generate reactive free radicals, exhibit good solubility in resin systems, and are well tolerated upon contact with human skin. The photoinitiator may be selected, for example, from acylphosphine oxides, such as monoacylphosphine oxide, diacylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, or others such as 2-hydroxy-methyl-1-phenylacetone, methyl benzoylformate, and methyl phenylglyoxylate.

[0063] Plasticizers enhance the tensile strength and flexibility of the SBC compositions and polymer blends disclosed herein. Preferably, the plasticizer consists of a liquid or mixture of liquid-saturated polyolefins compatible with the intermediate blocks (elastomer blocks) of the SBC. More preferably, the plasticizer may be selected from compounds having a pour point of less than or equal to 35°C. In the context of this disclosure, plasticizing oils are preferred, mineral plasticizing oils are preferred, especially mineral oils formed from purified mixtures of liquid-saturated hydrocarbons, which are compounds of alkane or cycloalkane nature or mixtures thereof in different proportions.

[0064] The preferred plasticizing mineral oil is a crystalline, transparent, water-white product free of toxic impurities and MOAH (mineral oil aromatics), and complies with the requirements of USAFDA 21 CFR 178.3620(a), White Mineral Oil; US Pharmacopeia; European Pharmacopoeia (Liquid Paraffin); and Europe Regulation (EU) 10 / 2011 for paraffin oils intended for use in plastic materials and articles intended for contact with food. The preferred mineral oil is medical-grade white oil with a specific gravity of 0.85 to 0.90 at 15°C.

[0065] Plasticizers can also be oligomers or other elastomers with sufficient compatibility with the rubbery intermediate blocks; in this case, they can be more accurately considered "toughening agents." Such toughening agents can be selected from a family of polymers including polybutadiene, polyisoprene, polyisobutylene, amorphous polyolefin copolymers of propylene and ethylene, butyl rubber, and other polymers known to have sufficient compatibility with the rubbery blocks. Functionalized or reactive toughening agents, such as acrylic or hydroxyl-modified polybutadiene, can also be used. These reactive toughening agents can participate in chemically crosslinked networks.

[0066] SBC compositions or miscible polymer blends according to embodiments of this disclosure are expressed in PHR (parts per hundred parts rubber), wherein the rubber is one or more of the SBCs. Exemplary ranges of components in the composition include:

[0067] ● Miscible polymers: 0.25 to 100 phr, preferably 5 to 50 phr

[0068] ● Plasticizer / toughening agent: 0 to 200 phr, preferably 20 to 75 phr

[0069] ● Crosslinking agent: 0.01 to 5 phr, preferably 0.05 to 1 phr

[0070] ● Photoinitiator: 0 to 5 phr, preferably 0 to 2 phr.

[0071] On the other hand, a method is provided for preparing an impregnated article from at least one SBC composition or miscible polymer blend disclosed herein, wherein a mold having an outer contour corresponding to the outer contour of the impregnated article to be prepared is impregnated in an impregnation solution containing the one or more SBC compositions or miscible polymer blends for a predetermined time, and the impregnated article is subsequently removed from the solution and dried.

[0072] The item, especially the dried item, can then be exposed to radiation, such as electron beams, gamma rays, UV or X-rays.

[0073] On the other hand, a film is provided comprising one or more SBC compositions or miscible polymer blends, wherein the film has a tensile strength greater than 17 MPa as measured according to ASTM 3577, and wherein the film is substantially insoluble in organic solvents.

[0074] "Very insoluble" can mean, for example, that at least 80% of the film is insoluble in or at least 95% of the film is insoluble in organic solvents that can be used in the medical field, such as methyl methacrylate (MMA) or ether.

[0075] On the other hand, elastomeric styrene-type block copolymer compositions or miscible polymer blends are provided, wherein the compositions have a tensile strength of at least 17 MPa and wherein the compositions are substantially insoluble in organic solvents.

[0076] "Substantially insoluble" can mean, for example, that at least 80% of the composition is insoluble in or at least 95% of the composition is insoluble in organic solvents that can be used in the medical field, such as methyl methacrylate (MMA) or ether.

[0077] On the other hand, films are provided that comprise one or more SBC compositions or miscible polymer blends according to any of the embodiments disclosed herein.

[0078] In any of the embodiments disclosed herein, the thickness of the film may be between about 10 micrometers and about 500 micrometers or between about 150 micrometers and about 250 micrometers.

[0079] In any of the embodiments disclosed herein, the thickness of the film may be less than 500 micrometers, or less than 400 micrometers, or less than 300 micrometers, or less than 200 micrometers.

[0080] On the other hand, a multilayer film is provided, the multilayer film comprising one or more layers or films, the one or more layers or films comprising the SBC compositions disclosed herein or miscible polymer blends.

[0081] On the other hand, a multilayer film is provided, the multilayer film comprising one or more layers or films, the one or more layers or films comprising an SBC composition or a miscible polymer blend, wherein the tensile strength of the composition or miscible polymer blend is at least 17 MPa, and wherein the composition or miscible polymer blend is substantially insoluble in organic solvents.

[0082] Multilayer films can be obtained by stacking several thin layers made of the same or different SBC compositions. Different SBC compositions, as disclosed in this invention, can be combined in different layers. Furthermore, at least one layer having a composition disclosed in this invention can be combined with other elastomers selected from: natural rubber, polybutadiene, polyisoprene, polychloroprene, butyl rubber, polyurethane, acrylic polymers and copolymers, silicone elastomers, other SBCs, cyclic block copolymers (CBCs), and blends thereof. It should be understood that the properties of the elastomers constituting each of the layers can be the same or different from each other.

[0083] According to this disclosure, SBS, SEBS, and butyl rubber are preferred components of multilayer films. In one embodiment, multilayer gloves comprising a laminate made of the compositions disclosed herein and butyl rubber provide enhanced resistance to penetration of chemicals such as methyl methacrylate monomers. Such gloves may comprise, for example, a thin butyl rubber layer on an outer layer and / or sandwiched between other layers comprising the SBC compositions disclosed herein.

[0084] The layers of the thin-walled elastic membrane may also contain other additives commonly used in the polymer industry, particularly in the glove industry, such as lubricants and anti-sticking agents, antistatic agents, primary and secondary antioxidants, colorants, processing aids, etc.

[0085] On the other hand, articles comprising one or more SBC compositions or miscible polymer blends as disclosed herein are provided.

[0086] The manufactured items can be medical devices, such as medical gloves, condoms, or personal protective equipment, such as laboratory gloves or cleaning industry gloves.

[0087] Membranes or multilayer membranes may also include active chemical substances.

[0088] The properties of the active substance can be selected according to the desired properties. The active chemical substance can be specifically selected from corrosion inhibitors, lubricants, chemical markers, phase change products, high-energy particle (radiation) moderators, reagents with disinfecting capabilities, odorants or humectants, dyes for detecting cuts, metal particles and mixtures thereof.

[0089] When the active chemical substance is a product with disinfecting capabilities, it is preferably selected from substances capable of causing substantial transient denaturation of proteins through simple contact via chemical reaction or through physicochemical action (such as a change in surface tension). Among such substances, biocides, such as quaternary ammonium chloride and more particularly dimethyldecylammonium chloride and benzalkonium chloride, biguanides, water-soluble salts of chlorhexidine, such as chlorhexidine digluconate, phthalaldehyde, phenolic derivatives such as hexachlorophenol or benzyl derivatives, formaldehyde, and nonionic surfactants containing at least one polyoxyethylene sequence, such as octyl styrene polyol (…). X100), hexamidine, iodinated polyvinylpyrrolidone compounds, nonionic surfactants with antiviral activity, sodium dichromate and potassium dichromate, and mixtures thereof.

[0090] This disclosure relates to compositions comprising SBCs capable of forming thin-walled elastic articles with improved mechanical properties through chemical and physical cross-linking. Detailed Implementation

[0091] Before disclosing and describing the compositions, components, articles, and / or methods of the present invention, it should be understood that, unless otherwise stated, the invention is not limited to the specific compositions, components, articles, methods, etc., as they can vary, unless otherwise stated. It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

[0092] It must also be noted that, unless otherwise stated, the singular forms “a,” “an,” and “the” used in the specification and appended claims include plural references. Thus, for example, a reference to “SBC” may include more than one SBC, and so on.

[0093] This article discloses advantageous SBC compositions and miscible polymer blends and their preparation methods.

[0094] In one exemplary embodiment, an elastomeric styrene-type block copolymer (SBC) composition is provided, comprising one or more SBCs and one or more polymers miscible with styrene-type end blocks of said one or more SBCs;

[0095] The block copolymer composition is physically crosslinked and chemically crosslinked;

[0096] The chemical crosslinking mentioned above includes covalent bonds between the chains of the SBC;

[0097] The physical crosslinking includes non-covalent interactions between the styrene-terminated blocks of the one or more SBCs and the one or more polymers miscible with the styrene-terminated blocks;

[0098] The one or more SBCs mentioned herein are selected from SIS, SBS, SIBS, S-isobutylene-S, SEBS, SEPS, SEEPS, or SBC, and are functionalized with reactive groups grafted into the intermediate rubber block, such as carboxylic acid groups, amino groups, alcohol groups, maleic anhydride groups, epoxy groups, isocyanate groups, and aziridinyl groups, or mixtures thereof; and

[0099] The one or more miscible polymers mentioned herein are selected from polystyrene resins, coumarone-indene resins, polyindene resins, poly(methylindene) resins, vinyltoluene-α-methylstyrene resins, α-methylstyrene resins, polyphenylene ethers, copolymers of alkyl aromatic monomers such as α-methylstyrene and p-methylstyrene, rosin esters, stylated terpenes, polyterpenes, terpene phenols, and mixtures thereof.

[0100] In another exemplary embodiment, an elastomeric styrene-type block copolymer (SBC) composition is provided, comprising one or more SBCs and one or more polymers miscible with styrene-type end blocks of said one or more SBCs;

[0101] The block copolymer composition is physically crosslinked and chemically crosslinked;

[0102] The chemical crosslinking mentioned above includes covalent bonds between the chains of the SBC;

[0103] The physical crosslinking includes non-covalent interactions between the styrene-terminated blocks of the one or more SBCs and the one or more polymers miscible with the styrene-terminated blocks;

[0104] The one or more SBCs mentioned herein are selected from SIS, SBS, SIBS, S-isobutylene-S, SEBS, SEPS, SEEPS, or SBC, and are functionalized with reactive groups grafted into the intermediate rubber block, such as carboxylic acid groups, amino groups, alcohol groups, maleic anhydride groups, epoxy groups, isocyanate groups, and aziridinyl groups, or mixtures thereof; and

[0105] The one or more miscible polymers mentioned herein are selected from polystyrene resins, coumarone-indene resins, polyindene resins, poly(methylindene) resins, vinyltoluene-α-methylstyrene resins, α-methylstyrene resins, polyphenylene ethers, copolymers of alkyl aromatic monomers such as α-methylstyrene and p-methylstyrene, rosin esters, stylated terpenes, polyterpenes, terpene phenols, and mixtures thereof, wherein the molecular weight (Mn) of the SBC is greater than 100,000 g / mol, and the molecular weight (Mn) of the miscible polymer is less than 10,000 g / mol.

[0106] In another exemplary embodiment, an elastomeric styrene-type block copolymer (SBC) composition is provided, comprising one or more SBCs and one or more polymers miscible with styrene-type end blocks of said one or more SBCs;

[0107] The block copolymer composition is physically crosslinked and chemically crosslinked;

[0108] The chemical crosslinking mentioned above includes covalent bonds between the chains of the SBC;

[0109] The physical crosslinking includes non-covalent interactions between the styrene-terminated blocks of the one or more SBCs and the one or more polymers miscible with the styrene-terminated blocks;

[0110] At least one of the SBCs contains reactive functional groups, such as double bonds, in its elastomer interblock to enable chemical cross-linking; and

[0111] The one or more miscible polymers mentioned herein are selected from polystyrene resins, coumarone-indene resins, polyindene resins, poly(methylindene) resins, vinyltoluene-α-methylstyrene resins, α-methylstyrene resins, polyphenylene ethers, copolymers of alkyl aromatic monomers such as α-methylstyrene and p-methylstyrene, rosin esters, stylated terpenes, polyterpenes, terpene phenols, and mixtures thereof, wherein the molecular weight (Mn) of the SBC is greater than 100,000 g / mol, and the molecular weight (Mn) of the miscible polymer is less than 10,000 g / mol.

[0112] In another exemplary embodiment, an elastomeric styrene-type block copolymer (SBC) composition is provided, comprising one or more SBCs and one or more polymers miscible with styrene-type end blocks of said one or more SBCs;

[0113] The block copolymer composition is physically crosslinked and chemically crosslinked;

[0114] The chemical crosslinking mentioned above includes covalent bonds between the chains of the SBC;

[0115] The physical crosslinking includes non-covalent interactions between the styrene-terminated blocks of the one or more SBCs and the one or more polymers miscible with the styrene-terminated blocks;

[0116] At least one of the SBCs contains reactive functional groups, such as double bonds, in its elastomer interblock to enable chemical cross-linking; and

[0117] The one or more miscible polymers mentioned herein are selected from polystyrene resins, α-methylstyrene resins, copolymers of alkyl aromatic monomers such as α-methylstyrene and p-methylstyrene, and mixtures thereof, wherein the molecular weight (Mn) of the SBC is greater than 100,000 g / mol, and the molecular weight (Mn) of the miscible polymer is less than 10,000 g / mol.

[0118] In another exemplary embodiment, a miscible polymer blend is provided, comprising one or more SBCs and one or more polymers miscible with styrene-type end blocks of said one or more SBCs;

[0119] The miscible polymer blends described therein are physically cross-linked and chemically cross-linked;

[0120] The chemical crosslinking mentioned above includes covalent bonds between the chains of the SBC;

[0121] The physical crosslinking includes non-covalent interactions between the styrene-terminated blocks of the one or more SBCs and the one or more polymers miscible with the styrene-terminated blocks;

[0122] The one or more SBCs mentioned herein are selected from SIS, SBS, SIBS, S-isobutylene-S, SEBS, SEPS, SEEPS, or SBC, and are functionalized with reactive groups grafted into the intermediate rubber block, such as carboxylic acid groups, amino groups, alcohol groups, maleic anhydride groups, epoxy groups, isocyanate groups, and aziridinyl groups, or mixtures thereof; and

[0123] The one or more miscible polymers mentioned herein are selected from polystyrene resins, coumarone-indene resins, polyindene resins, poly(methylindene) resins, vinyltoluene-α-methylstyrene resins, α-methylstyrene resins, polyphenylene ethers, copolymers of alkyl aromatic monomers such as α-methylstyrene and p-methylstyrene, rosin esters, stylated terpenes, polyterpenes, terpene phenols, and mixtures thereof.

[0124] In another exemplary embodiment, a miscible polymer blend is provided, comprising one or more SBCs and one or more polymers miscible with styrene-type end blocks of said one or more SBCs;

[0125] The miscible polymer blends described therein are physically cross-linked and chemically cross-linked;

[0126] The chemical crosslinking mentioned above includes covalent bonds between the chains of the SBC;

[0127] The physical crosslinking includes non-covalent interactions between the styrene-terminated blocks of the one or more SBCs and the one or more polymers miscible with the styrene-terminated blocks;

[0128] The one or more SBCs mentioned herein are selected from SIS, SBS, SIBS, S-isobutylene-S, SEBS, SEPS, SEEPS, or SBC, and are functionalized with reactive groups grafted into the intermediate rubber block, such as carboxylic acid groups, amino groups, alcohol groups, maleic anhydride groups, epoxy groups, isocyanate groups, and aziridinyl groups, or mixtures thereof; and

[0129] The one or more miscible polymers mentioned herein are selected from polystyrene resins, coumarone-indene resins, polyindene resins, poly(methylindene) resins, vinyltoluene-α-methylstyrene resins, α-methylstyrene resins, polyphenylene ethers, copolymers of alkyl aromatic monomers such as α-methylstyrene and p-methylstyrene, rosin esters, stylated terpenes, polyterpenes, terpene phenols, and mixtures thereof, wherein the molecular weight (Mn) of the SBC is greater than 100,000 g / mol, and the molecular weight (Mn) of the miscible polymer is less than 10,000 g / mol.

[0130] In another exemplary embodiment, a miscible polymer blend is provided, comprising one or more SBCs and one or more polymers miscible with styrene-type end blocks of said one or more SBCs;

[0131] The miscible polymer blends described therein are physically cross-linked and chemically cross-linked;

[0132] The chemical crosslinking mentioned above includes covalent bonds between the chains of the SBC;

[0133] The physical crosslinking includes non-covalent interactions between the styrene-terminated blocks of the one or more SBCs and the one or more polymers miscible with the styrene-terminated blocks;

[0134] At least one of the SBCs contains reactive functional groups, such as double bonds, in its elastomer interblock to enable chemical cross-linking; and

[0135] The one or more miscible polymers mentioned herein are selected from polystyrene resins, coumarone-indene resins, polyindene resins, poly(methylindene) resins, vinyltoluene-α-methylstyrene resins, α-methylstyrene resins, polyphenylene ethers, copolymers of alkyl aromatic monomers such as α-methylstyrene and p-methylstyrene, rosin esters, stylated terpenes, polyterpenes, terpene phenols, and mixtures thereof, wherein the molecular weight (Mn) of the SBC is greater than 100,000 g / mol, and the molecular weight (Mn) of the miscible polymer is less than 10,000 g / mol.

[0136] In another exemplary embodiment, a miscible polymer blend is provided, comprising one or more SBCs and one or more polymers miscible with styrene-type end blocks of said one or more SBCs;

[0137] The miscible polymer blends described therein are physically cross-linked and chemically cross-linked;

[0138] The chemical crosslinking mentioned above includes covalent bonds between the chains of the SBC;

[0139] The physical crosslinking includes non-covalent interactions between the styrene-terminated blocks of the one or more SBCs and the one or more polymers miscible with the styrene-terminated blocks;

[0140] At least one of the SBCs contains reactive functional groups, such as double bonds, in its elastomer interblock to enable chemical cross-linking; and

[0141] The one or more miscible polymers mentioned herein are selected from polystyrene resins, α-methylstyrene resins, copolymers of alkyl aromatic monomers such as α-methylstyrene and p-methylstyrene, and mixtures thereof, wherein the molecular weight (Mn) of the SBC is greater than 100,000 g / mol, and the molecular weight (Mn) of the miscible polymer is less than 10,000 g / mol.

[0142] In another exemplary embodiment, an elastomeric styrene block copolymer composition is provided, comprising:

[0143] (a) One or more SBCs;

[0144] (b) One or more polymers miscible with the polystyrene-terminated blocks of the one or more SBCs; and

[0145] (c) One or more crosslinking agents capable of inducing covalent bonding between the chains of the one or more SBCs;

[0146] The one or more SBCs mentioned therein are selected from SIS, SBS, SIBS, S-isobutylene-S, SEBS, SEPS, SEEPS or SBC, and they are functionalized with reactive groups grafted into the intermediate rubber block, such as carboxylic acid group, amino group, alcohol group, maleic anhydride group, epoxy group, isocyanate group and aziridinyl group or mixtures thereof.

[0147] The one or more miscible polymers mentioned herein are selected from polystyrene resins, coumarone-indene resins, polyindene resins, poly(methylindene) resins, vinyltoluene-α-methylstyrene resins, α-methylstyrene resins, polyphenylene ethers, copolymers of alkyl aromatic monomers such as α-methylstyrene and p-methylstyrene, rosin esters, styrenated terpenes, polyterpenes, terpene phenols, and mixtures thereof; and

[0148] The one or more crosslinking agents mentioned herein are selected from aromatic, aliphatic, and heteroaromatic monomers and oligomers containing at least two carbon-carbon double bonds, such as: polyfunctional acrylates, such as trimethylolpropane triacrylate (TMPTA), trimethylolpropane trimethacrylate (TMPTMA), epoxy acrylates, urethane acrylates; triallyl cyanurate, triallyl isocyanurate; functional thiols, such as 1,8-dimercapto-3,6-dioxaoctane, trimethylolpropane-tri-3-mercaptopropionate, pentaerythritol tetra-3-mercaptopropionate, ethoxylated trimethylolpropane tri(3-mercaptopropionate); and other polyfunctional compounds having vinyl or allyl groups; and mixtures thereof.

[0149] In another exemplary embodiment, an elastomeric styrene block copolymer composition is provided, comprising:

[0150] (a) One or more SBCs;

[0151] (b) One or more polymers miscible with the polystyrene-terminated blocks of the one or more SBCs; and

[0152] (c) One or more crosslinking agents capable of inducing covalent bonding between the chains of the one or more SBCs;

[0153] The one or more SBCs mentioned therein are selected from SIS, SBS, SIBS, S-isobutylene-S, SEBS, SEPS, SEEPS or SBC, and they are functionalized with reactive groups grafted into the intermediate rubber block, such as carboxylic acid group, amino group, alcohol group, maleic anhydride group, epoxy group, isocyanate group and aziridinyl group or mixtures thereof.

[0154] The one or more miscible polymers mentioned herein are selected from polystyrene resins, coumarone-indene resins, polyindene resins, poly(methylindene) resins, vinyltoluene-α-methylstyrene resins, α-methylstyrene resins, polyphenylene ethers, copolymers of alkyl aromatic monomers such as α-methylstyrene and p-methylstyrene, rosin esters, styrenated terpenes, polyterpenes, terpene phenols, and mixtures thereof; and

[0155] The one or more crosslinking agents are selected from aromatic, aliphatic, and heteroaromatic monomers and oligomers containing at least two carbon-carbon double bonds, such as: polyfunctional acrylates, such as trimethylolpropane triacrylate (TMPTA), trimethylolpropane trimethacrylate (TMPTMA), epoxy acrylates, urethane acrylates; triallyl cyanurate, triallyl isocyanurate; functional thiols, such as 1,8-dimercapto-3,6-dioxaoctane, trimethylolpropane-tri-3-mercaptopropionate, pentaerythritol tetra-3-mercaptopropionate, ethoxylated trimethylolpropane tri(3-mercaptopropionate); and other polyfunctional compounds having vinyl or allyl groups; and mixtures thereof, wherein the molecular weight (Mn) of the SBC is greater than 100,000 g / mol, and the molecular weight (Mn) of the miscible polymer is less than 10,000 g / mol.

[0156] In another exemplary embodiment, an elastomeric styrene block copolymer composition is provided, comprising:

[0157] (a) One or more SBCs;

[0158] (b) One or more polymers miscible with the polystyrene-terminated blocks of the one or more SBCs; and

[0159] (c) One or more crosslinking agents capable of inducing covalent bonding between the chains of the one or more SBCs;

[0160] At least one of the SBCs contains reactive functional groups, such as double bonds, in its elastomer interblock to enable chemical cross-linking; and

[0161] The one or more miscible polymers mentioned herein are selected from polystyrene resins, coumarone-indene resins, polyindene resins, poly(methylindene) resins, vinyltoluene-α-methylstyrene resins, α-methylstyrene resins, polyphenylene ethers, copolymers of alkyl aromatic monomers such as α-methylstyrene and p-methylstyrene, rosin esters, styrenated terpenes, polyterpenes, terpene phenols, and mixtures thereof; and

[0162] The one or more crosslinking agents are selected from aromatic, aliphatic, and heteroaromatic monomers and oligomers containing at least two carbon-carbon double bonds, such as: polyfunctional acrylates, such as trimethylolpropane triacrylate (TMPTA), trimethylolpropane trimethacrylate (TMPTMA), epoxy acrylates, urethane acrylates; triallyl cyanurate, triallyl isocyanurate; functional thiols, such as 1,8-dimercapto-3,6-dioxaoctane, trimethylolpropane-tri-3-mercaptopropionate, pentaerythritol tetra-3-mercaptopropionate, ethoxylated trimethylolpropane tri(3-mercaptopropionate); and other polyfunctional compounds having vinyl or allyl groups; and mixtures thereof, wherein the molecular weight (Mn) of the SBC is greater than 100,000 g / mol, and the molecular weight (Mn) of the miscible polymer is less than 10,000 g / mol.

[0163] In another exemplary embodiment, an elastomeric styrene block copolymer composition is provided, comprising:

[0164] (a) One or more SBCs;

[0165] (b) One or more polymers miscible with the polystyrene-terminated blocks of the one or more SBCs; and

[0166] (c) One or more crosslinking agents capable of inducing covalent bonding between the chains of the one or more SBCs;

[0167] At least one of the SBCs contains reactive functional groups, such as double bonds, in its elastomer interblock to enable chemical cross-linking; and

[0168] The one or more miscible polymers mentioned above are selected from polystyrene resins, α-methylstyrene resins, copolymers of alkyl aromatic monomers such as α-methylstyrene and p-methylstyrene, and mixtures thereof; and

[0169] The one or more crosslinking agents are selected from aromatic, aliphatic, and heteroaromatic monomers and oligomers containing at least two carbon-carbon double bonds, such as: polyfunctional acrylates, such as trimethylolpropane triacrylate (TMPTA), trimethylolpropane trimethacrylate (TMPTMA), epoxy acrylates, urethane acrylates; triallyl cyanurate, triallyl isocyanurate; functional thiols, such as 1,8-dimercapto-3,6-dioxaoctane, trimethylolpropane-tri-3-mercaptopropionate, pentaerythritol tetra-3-mercaptopropionate, ethoxylated trimethylolpropane tri(3-mercaptopropionate); and other polyfunctional compounds having vinyl or allyl groups; and mixtures thereof, wherein the molecular weight (Mn) of the SBC is greater than 100,000 g / mol, and the molecular weight (Mn) of the miscible polymer is less than 10,000 g / mol.

[0170] In another exemplary embodiment, the layer comprising the thin-walled elastic membrane may also contain other additives commonly used in the polymer industry, particularly in the glove industry, such as lubricants, anti-sticking agents, antistatic agents, primary and secondary antioxidants, colorants, processing aids, etc.

[0171] In another exemplary embodiment, an elastomeric styrene block copolymer composition is provided, comprising:

[0172] (a) One or more SBCs;

[0173] (b) One or more polymers miscible with the polystyrene-terminated blocks of the one or more SBCs; and

[0174] (c) One or more crosslinking agents capable of inducing covalent bonding between the chains of the one or more SBCs;

[0175] The one or more SBCs mentioned above are selected from SIS or SBS or mixtures thereof;

[0176] At least one of the SBCs contains reactive functional groups, such as double bonds, in its elastomer interblock to enable chemical cross-linking; and

[0177] The one or more miscible polymers mentioned above are selected from polystyrene resins, α-methylstyrene resins, copolymers of alkyl aromatic monomers such as α-methylstyrene and p-methylstyrene, and mixtures thereof; and

[0178] The one or more crosslinking agents are selected from functional thiols such as 1,8-dimercapto-3,6-dioxaoctane, trimethylolpropane-tri-3-mercaptopropionate, pentaerythritol tetra-3-mercaptopropionate, ethoxylated trimethylolpropane tri(3-mercaptopropionate), and mixtures thereof, wherein the molecular weight (Mn) of the SBC is greater than 100,000 g / mol, and the molecular weight (Mn) of the miscible polymer is less than 10,000 g / mol.

[0179] In another exemplary embodiment, a method for preparing an SBC composition is provided, comprising the steps of: one or more SBCs, one or more polymers miscible with one or more polystyrene-terminated blocks of the one or more SBCs; and one or more crosslinking agents capable of inducing covalent bonding between the chains of the one or more SBCs;

[0180] The one or more SBCs mentioned therein are selected from SIS, SBS, SIBS, S-isobutylene-S, SEBS, SEPS, SEEPS or SBC, and they are functionalized with reactive groups grafted into the intermediate rubber block, such as carboxylic acid group, amino group, alcohol group, maleic anhydride group, epoxy group, isocyanate group and aziridinyl group or mixtures thereof.

[0181] The one or more miscible polymers mentioned herein are selected from polystyrene resins, coumarone-indene resins, polyindene resins, poly(methylindene) resins, vinyltoluene-α-methylstyrene resins, α-methylstyrene resins, polyphenylene ethers, copolymers of alkyl aromatic monomers such as α-methylstyrene and p-methylstyrene, rosin esters, styrenated terpenes, polyterpenes, terpene phenols, and mixtures thereof; and

[0182] The one or more crosslinking agents mentioned herein are selected from aromatic, aliphatic, and heteroaromatic monomers and oligomers containing at least two carbon-carbon double bonds, such as: polyfunctional acrylates, such as trimethylolpropane triacrylate (TMPTA), trimethylolpropane trimethacrylate (TMPTMA), epoxy acrylates, urethane acrylates; triallyl cyanurate, triallyl isocyanurate; functional thiols, such as 1,8-dimercapto-3,6-dioxaoctane, trimethylolpropane-tri-3-mercaptopropionate, pentaerythritol tetra-3-mercaptopropionate, ethoxylated trimethylolpropane tri(3-mercaptopropionate); and other polyfunctional compounds having vinyl or allyl groups; and mixtures thereof.

[0183] In another exemplary embodiment, a method for preparing an SBC composition is provided, comprising the steps of: one or more SBCs, one or more polymers miscible with one or more polystyrene-terminated blocks of the one or more SBCs; and one or more crosslinking agents capable of inducing covalent bonding between the chains of the one or more SBCs;

[0184] The one or more SBCs mentioned therein are selected from SIS, SBS, SIBS, S-isobutylene-S, SEBS, SEPS, SEEPS or SBC, and they are functionalized with reactive groups grafted into the intermediate rubber block, such as carboxylic acid group, amino group, alcohol group, maleic anhydride group, epoxy group, isocyanate group and aziridinyl group or mixtures thereof.

[0185] The one or more miscible polymers mentioned herein are selected from polystyrene resins, coumarone-indene resins, polyindene resins, poly(methylindene) resins, vinyltoluene-α-methylstyrene resins, α-methylstyrene resins, polyphenylene ethers, copolymers of alkyl aromatic monomers such as α-methylstyrene and p-methylstyrene, rosin esters, styrenated terpenes, polyterpenes, terpene phenols, and mixtures thereof; and

[0186] The one or more crosslinking agents are selected from aromatic, aliphatic, and heteroaromatic monomers and oligomers containing at least two carbon-carbon double bonds, such as: polyfunctional acrylates, such as trimethylolpropane triacrylate (TMPTA), trimethylolpropane trimethacrylate (TMPTMA), epoxy acrylates, urethane acrylates; triallyl cyanurate, triallyl isocyanurate; functional thiols, such as 1,8-dimercapto-3,6-dioxaoctane, trimethylolpropane-tri-3-mercaptopropionate, pentaerythritol tetra-3-mercaptopropionate, ethoxylated trimethylolpropane tri(3-mercaptopropionate); and other polyfunctional compounds having vinyl or allyl groups; and mixtures thereof, wherein the molecular weight (Mn) of the SBC is greater than 100,000 g / mol, and the molecular weight (Mn) of the miscible polymer is less than 10,000 g / mol.

[0187] In another exemplary embodiment, a method for preparing an SBC composition is provided, comprising the steps of: one or more SBCs, one or more polymers miscible with one or more polystyrene-terminated blocks of the one or more SBCs; and one or more crosslinking agents capable of inducing covalent bonding between the chains of the one or more SBCs;

[0188] At least one of the SBCs contains reactive functional groups, such as double bonds, in its elastomer interblock to enable chemical cross-linking; and

[0189] The one or more miscible polymers mentioned herein are selected from polystyrene resins, coumarone-indene resins, polyindene resins, poly(methylindene) resins, vinyltoluene-α-methylstyrene resins, α-methylstyrene resins, polyphenylene ethers, copolymers of alkyl aromatic monomers such as α-methylstyrene and p-methylstyrene, rosin esters, styrenated terpenes, polyterpenes, terpene phenols, and mixtures thereof; and

[0190] The one or more crosslinking agents are selected from aromatic, aliphatic, and heteroaromatic monomers and oligomers containing at least two carbon-carbon double bonds, such as: polyfunctional acrylates, such as trimethylolpropane triacrylate (TMPTA), trimethylolpropane trimethacrylate (TMPTMA), epoxy acrylates, urethane acrylates; triallyl cyanurate, triallyl isocyanurate; functional thiols, such as 1,8-dimercapto-3,6-dioxaoctane, trimethylolpropane-tri-3-mercaptopropionate, pentaerythritol tetra-3-mercaptopropionate, ethoxylated trimethylolpropane tri(3-mercaptopropionate); and other polyfunctional compounds having vinyl or allyl groups; and mixtures thereof, wherein the molecular weight (Mn) of the SBC is greater than 100,000 g / mol, and the molecular weight (Mn) of the miscible polymer is less than 10,000 g / mol.

[0191] In another exemplary embodiment, a method for preparing an SBC composition is provided, comprising the steps of: one or more SBCs, one or more polymers miscible with one or more polystyrene-terminated blocks of the one or more SBCs; and one or more crosslinking agents capable of inducing covalent bonding between the chains of the one or more SBCs;

[0192] At least one of the SBCs contains reactive functional groups, such as double bonds, in its elastomer interblock to enable chemical cross-linking; and

[0193] The one or more miscible polymers mentioned above are selected from polystyrene resins, α-methylstyrene resins, copolymers of alkyl aromatic monomers such as α-methylstyrene and p-methylstyrene, and mixtures thereof; and

[0194] The one or more crosslinking agents are selected from aromatic, aliphatic, and heteroaromatic monomers and oligomers containing at least two carbon-carbon double bonds, such as: polyfunctional acrylates, such as trimethylolpropane triacrylate (TMPTA), trimethylolpropane trimethacrylate (TMPTMA), epoxy acrylates, urethane acrylates; triallyl cyanurate, triallyl isocyanurate; functional thiols, such as 1,8-dimercapto-3,6-dioxaoctane, trimethylolpropane-tri-3-mercaptopropionate, pentaerythritol tetra-3-mercaptopropionate, ethoxylated trimethylolpropane tri(3-mercaptopropionate); and other polyfunctional compounds having vinyl or allyl groups; and mixtures thereof, wherein the molecular weight (Mn) of the SBC is greater than 100,000 g / mol, and the molecular weight (Mn) of the miscible polymer is less than 10,000 g / mol.

[0195] In another exemplary embodiment, a method for preparing an SBC composition is provided, comprising the steps of: one or more SBCs, one or more polymers miscible with one or more polystyrene-terminated blocks of the one or more SBCs; and one or more crosslinking agents capable of inducing covalent bonding between the chains of the one or more SBCs;

[0196] At least one of the SBCs contains reactive functional groups, such as double bonds, in its elastomer interblock to enable chemical cross-linking; and

[0197] The one or more miscible polymers mentioned above are selected from polystyrene resins, α-methylstyrene resins, copolymers of alkyl aromatic monomers such as α-methylstyrene and p-methylstyrene, and mixtures thereof; and

[0198] The one or more crosslinking agents are selected from functional thiols, such as 1,8-dimercapto-3,6-dioxaoctane, trimethylolpropane-tri-3-mercaptopropionate, pentaerythritol tetra-3-mercaptopropionate, ethoxylated trimethylolpropane tri(3-mercaptopropionate); and mixtures thereof, wherein the molecular weight (Mn) of the SBC is greater than 100,000 g / mol, and the molecular weight (Mn) of the miscible polymer is less than 10,000 g / mol.

[0199] In another exemplary embodiment, a method is provided for preparing an impregnated article from at least one SBC composition or miscible polymer blend disclosed in any of the exemplary embodiments described herein, wherein a mold having an outer contour corresponding to the outer contour of the impregnated article to be prepared is impregnated in an impregnation solution containing one or more of the SBC compositions or miscible polymer blends for a predetermined time, and the impregnated article is subsequently removed from the solution and dried.

[0200] Articles, especially dried articles, can be subsequently exposed to radiation, such as electron beams, gamma rays, UV or X-ray radiation.

[0201] In another exemplary embodiment, a film comprising one or more SBC compositions or miscible polymer blends disclosed in any of the exemplary embodiments described herein is provided, wherein the film has a tensile strength greater than 17 MPa when measured according to ASTM 3577 and wherein the film is substantially insoluble in organic solvents.

[0202] In another exemplary embodiment, a film comprising one or more SBC compositions or miscible polymer blends according to any of the preferred embodiments described herein is provided.

[0203] In any of the exemplary embodiments disclosed herein, the thickness of the film may be between about 10 micrometers and about 500 micrometers or between about 150 micrometers and about 250 micrometers.

[0204] In any of the exemplary embodiments disclosed herein, the thickness of the film may be less than 500 micrometers, or less than 400 micrometers, or less than 300 micrometers, or less than 200 micrometers.

[0205] In another exemplary embodiment, articles of manufacture, such as gloves or condoms, are provided comprising one or more SBC compositions or miscible polymer blends disclosed in any of the exemplary embodiments disclosed herein.

[0206] Mechanical properties

[0207] The SBC composition or miscible polymer blend according to this disclosure may have a modulus at 100% elongation of less than 1.0 MPa or less than 0.70 MPa.

[0208] The thin-walled elastic articles according to this disclosure may have a modulus at 100% elongation of less than 1.0 MPa or less than 0.70 MPa.

[0209] The thin-walled elastic articles according to this disclosure may have a breaking force of greater than 9N (measured with an unaged film) in accordance with EN455-2 and ISO 10282.

[0210] The thin-walled elastic articles according to this disclosure may have tensile strengths conforming to ASTM D3577, i.e., greater than 17 MPa (unaged film).

[0211] SBC compositions or miscible polymer blends or thin-walled elastic articles may have any combination of the mechanical properties disclosed above.

[0212] Composition

[0213] The compositions according to embodiments of this disclosure are expressed in PHR (parts per hundred parts rubber), wherein the rubber is one or more of the SBCs. Exemplary ranges of components in the compositions include:

[0214] ● Miscible polymers: 0.25 to 100 phr, preferably 5 to 50 phr

[0215] ● Plasticizer / toughening agent: 0 to 200 phr, preferably 20 to 75 phr

[0216] ● Crosslinking agent: 0.01 to 5 phr, preferably 0.05 to 1 phr

[0217] ● Photoinitiator: 0 to 5 phr, preferably 0 to 2 phr.

[0218] Definition and composition

[0219] Thin-walled, elastically impregnated articles, such as gloves (particularly medical gloves) and condoms, as disclosed herein, may have a thickness of about 10 to about 500 micrometers or about 150 to about 250 micrometers.

[0220] Impregnated articles may be single-layered or multi-layered. Multi-layered articles may include layers comprising the same polymer composition or different polymer compositions.

[0221] Example

[0222] The following examples describe compositions according to this disclosure and are intended to illustrate the disclosure. These examples should not be construed as limiting the scope of the disclosure in any way.

[0223] It should be understood that although this disclosure has been described in conjunction with specific embodiments thereof, the foregoing description is intended to be illustrative and not to limit the scope of this disclosure. Other aspects, advantages, and modifications will be apparent to those skilled in the art to which this disclosure pertains. Therefore, the examples given are intended to provide those skilled in the art with a complete disclosure and description of how to prepare and use the disclosed compositions, and are not intended to limit the scope of this disclosure.

[0224] Example 1

[0225] The following examples demonstrate the improved performance (mechanical properties and chemical resistance) of the compositions according to this disclosure.

[0226] A styrene-butadiene-styrene copolymer (SBS) with a viscosity of 150 mPa·s in toluene (10%) at 25 °C, a miscible polymer based on styrene and substituted styrene (Mn = 800 g / mol, polydispersity index = 2.8), a plasticizer in the form of paraffin oil with a viscosity of 68 mPa·s at 40 °C, and a crosslinking agent in the form of trimethylpropane tris(3-mercaptopropionate) were dissolved in a mixture of methylcyclohexane and toluene (8:2) to form a solution with a solid content of 18% by weight.

[0227] The table below shows the use of different amounts of crosslinking agent and miscible polymers (“P”).

[0228] The amount of plasticizer is 50 phr, and 1 phr of polyphenolic antioxidant is added to the polymer solution.

[0229] The solution was stored in a suitable container at ambient temperature, with the container capped to prevent solvent evaporation. After the ceramic mold was immersed in the solution at a controlled immersion rate using an immersion robot, the membrane was obtained after the solvent evaporated. The membrane was dried at 70°C for 1 hour before peeling, and then finally dried at 50°C for 6 hours to remove trace amounts of residual solvent.

[0230] The membrane was then exposed to an electron beam radiation dose of 25 ± 2 kGy.

[0231] The chemical resistance of irradiated membranes can be evaluated using different methods. Ideally, the test methods should reproduce the conditions of actual exposure to chemicals.

[0232] In this embodiment, the SBC composition is intended for use in gloves, therefore the following tests were used to evaluate the film's chemical resistance:

[0233] 1) Swab test: Deposit 0.5g of pure methyl methacrylate monomer onto a cotton swab, then apply the swab to the membrane pre-stressed with slight tension. The contact time under slight pressure is 10 seconds. Repeat the test three times, then check the membrane resistance.

[0234] 2) Swelling test: Cut a 25mm diameter disc from the membrane and place it in a beaker containing 20ml of MEK with slight agitation for 5 minutes. After 5 minutes, remove the disc, clean the outer surface with tissue paper, and measure the disc diameter. The swelling rate is measured as 100*(expanded diameter (mm) – 25) / 25.

[0235] The mechanical properties of surgical gloves are measured according to ASTM 3577. For unaged synthetic Type II materials, the lower limit of tensile strength is 17 MPa.

[0236] The results are listed in the table below:

[0237]

[0238] These results demonstrate that SBS membranes can be effectively chemically crosslinked with trimethylolpropane tris(3-mercaptopropionate).

[0239] This example demonstrates that compositions combining SBC, crosslinking agents, and miscible polymers exhibit better mechanical properties than the following:

[0240] - SBC only (Reference 1)

[0241] -SBC combined with miscible polymers, without cross-linking agents (Ref. 2)

[0242] -SBS combined with a crosslinking agent results in an immiscible polymer (Ref. 4)

[0243] Reference 3 also demonstrates significantly improved chemical resistance compared to References 1 or 2. Finally, it can be seen that the gloves from Reference 3 are the only samples that meet the ASTM specifications regarding tensile strength. The resulting film is also very soft (modulus at 100% elongation = 0.68 MPa).

[0244] Example 2

[0245] The styrene-isoprene-styrene copolymer (SIS), which contains a styrene-isoprene diblock copolymer and has a viscosity of 45 mPa·s in toluene (10% concentration) at 25°C, is used instead of the SBS copolymer used in references 1 to 4.

[0246] This miscible polymer is based on styrene and substituted styrene (Mn = 800 g / mol, polydispersity index = 2.8) at a dosage of 20 phr, and contains no plasticizers or toughening agents. The crosslinking agent is trimethylolpropane trimethacrylate at a dosage of 1 phr.

[0247] For references 1 to 4, after solvent evaporation, a thin film was obtained, which was then dried to remove any trace amounts of residual solvent and then exposed to an electron beam radiation dose of 50 ± 3 kGy.

[0248] The film has a mechanical strength of 17.1 MPa and exhibits excellent chemical resistance in swab tests.

[0249] Example 3

[0250] Multilayer films were prepared using a combination of the following polymers:

[0251] -The styrene-butadiene-styrene block copolymer composition described in Reference 3 above

[0252] The first layer is 80±10μm thick;

[0253] - A second layer with a thickness of 140 ± 20 μm is composed of high molecular weight styrene-ethylene / butene-styrene (SEBS). This SEBS has a radial structure, a viscosity of 75 cp in toluene (5%), and contains 31% polystyrene. The miscible polymer is based on styrene and substituted styrene (Mn = 800 g / mol, polydispersity index = 2.8) at a dosage of 25 phr, and a plasticizer at a dosage of 60 phr. The crosslinking agent is trimethylpropane tris(3–) at a dosage of 0.2 phr.

[0254] Mercaptopropionate).

[0255] The multilayer film was exposed to an electron beam at 40 kGy ± 3.

[0256] Analysis of the membrane showed a tensile strength of 20.5 MPa and excellent resistance in swab tests.

[0257] For the sake of brevity, this document only explicitly discloses certain ranges. However, a range beginning with any lower limit can be combined with any upper limit to describe a range that is not explicitly stated, and a range beginning with any lower limit can be combined with any other lower limit to describe a range that is not explicitly stated, and in the same way, a range beginning with any upper limit can be combined with any other upper limit to describe a range that is not explicitly stated.

[0258] All cited references are incorporated herein by reference in their entirety, as all permissions permit such incorporation and such incorporation achieves the degree to which such disclosure is consistent with the description of this disclosure.

Claims

1. A method for preparing an SBC composition, comprising the following steps: A combination of one or more SBCs, one or more polymers miscible with one or more polystyrene-terminated blocks of the one or more SBCs; and one or more crosslinking agents capable of inducing covalent bonding between the chains of the one or more SBCs. The molecular weight (Mn) of one or more of the SBCs is greater than 100,000 g / mol; The number-average molecular weight (Mn) of the miscible polymer is less than 10,000 g / mol; The miscible polymer has a molecular weight polydispersity index of 2.0 to 3.

0. The SBC composition comprises one or more plasticizers and / or toughening agents compatible with the elastomeric intermediate block of the one or more SBCs, wherein the amount of the one or more plasticizers and / or toughening agents used is 20 to 75 phr; and The miscible polymers mentioned herein are selected from the group consisting of polystyrene resins, coumarone-indene resins, polyindene resins, poly(methylindene) resins, vinyltoluene-α-methylstyrene resins, α-methylstyrene resins, polyphenylene ethers, and copolymers of alkyl aromatic monomers.

2. The method of claim 1, wherein the one or more SBCs independently comprise fully unsaturated, partially unsaturated, or fully saturated elastomeric intermediate blocks.

3. The method of claim 1, wherein the one or more SBCs comprise fully saturated elastomeric intermediate blocks that are cleavable upon exposure to radiation.

4. The method of claim 1, wherein the one or more SBCs are selected from the group consisting of SIS, SBS, SIBS, S-isobutylene-S, SEBS, SEPS, SEEPS, or SBCs, which are functionalized with reactive groups grafted into the intermediate rubber block.

5. The method of claim 1, wherein the at least one SBC has an elastomeric intermediate block comprising reactive functional groups.

6. The method according to claim 1, wherein the number average molecular weight (Mn) of the miscible polymer is less than 3,000 g / mol.

7. The method of claim 1, wherein the at least one SBC contains double bonds in its elastomeric intermediate block to enable chemical crosslinking; and wherein the one or more miscible polymers are selected from the group consisting of: polystyrene resins, coumarone-indene resins, polyindene resins, poly(methylindene) resins, vinyltoluene-α-methylstyrene resins, polyphenylene ethers, and copolymers of alkyl aromatic monomers.

8. The method according to claim 1, wherein the crosslinking agent is selected from polyfunctional acrylates.

9. The method according to claim 1, wherein the crosslinking agent is a metal salt, an amine crosslinking agent selected from organic amines, organic diamines and organic polyamines, or a polyol.

10. The method of claim 1, wherein the crosslinking agent is selected from conventional sulfur, metal oxides and accelerators, which are commonly used in rubber vulcanization.

11. The method of claim 1, wherein the crosslinking agent is selected from dithiols, trithiols, and tetrathiols whose backbone contains ether or ester groups.

12. The method according to any one of claims 1 to 11, wherein the composition is crosslinked by applying radiation.

13. The method according to any one of claims 1 to 11, wherein the crosslinking of the composition is initiated or enhanced by one or a mixture of free radical photoinitiators.

14. The method of claim 13, wherein the radical photoinitiator is selected from acylphosphine oxide.

15. The method of claim 13, wherein the radical photoinitiator is selected from the group consisting of monoacylphosphine oxide, diacylphosphine oxide, and 2,4,6-trimethylbenzoyldiphenylphosphine oxide.

16. The method of claim 1, wherein the plasticizer comprises a mixture of liquid saturated polyolefins compatible with the middle block of the SBC.

17. The method of claim 1, wherein the plasticizer comprises plasticizing oil.

18. The method according to claim 1, wherein the toughening agent is selected from polybutadiene, polyisoprene, polyisobutylene, amorphous polyolefin copolymers of propylene and ethylene, and butyl rubber.

19. The method of claim 1, further comprising a lubricant, an antistatic agent, a primary and secondary antioxidant, a colorant, or a processing aid.

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