摘要:
A thermoplastic vulcanizate composition containing a thermoplastic and a functionalized copolymer of para-alkylstyrene-isoolefin is free radically cured, as for example, with a peroxide to yield a product having low impurities and good clarity. The thermoplastic typically can be a polyolefin.
摘要:
Thermoplastic elastomer compositions which have good high temperature end use and good oil swell resistance are made by blending a high melting thermoplastic polymer containing a non-polar rubber and a polar rubber. Alternatively, a high melting thermoplastic polymer containing a non-polar rubber or a polar rubber or both is blended with a polyolefin thermoplastic polymer containing a non-polar rubber, or a polar rubber, or both. The composition is dynamically vulcanized. The cured multi-component thermoplastic elastomer compositions exhibit good end use properties such as hardness, tensile strength, modulus, flexibility.
摘要:
Thermoplastic elastomer compositions which have good high temperature end use and good oil swell resistance are made by blending a high melting thermoplastic polymer containing a non-polar rubber and a polar rubber. Alternatively, a high melting thermoplastic polymer containing a non-polar rubber or a polar rubber or both is blended with a polyolefin thermoplastic polymer containing a non-polar rubber, or a polar rubber, or both. The composition is dynamically vulcanized. The cured multi-component thermoplastic elastomer compositions exhibit good end use properties such as hardness, tensile strength, modulus, flexibility.
摘要:
Thermoplastic vulcanizates from semicrystalline polyolefins and blends of crosslinked rubbers are disclosed. The blends are a mixture of at least two rubbers. One rubber is a copolymer predominantly of C.sub.4 to C.sub.7 isomonoolefins (e.g. isobutylene), along with optional monomers of conjugated dienes and/or p-alkylstyrene. This copolymer is optionally halogenated. The second rubber is ethylene/propylene rubber, natural rubber or a rubber polymerized predominantly from a conjugated diene. Such rubbers include polybutadiene, nitrile rubber, butadiene-styrene copolymers or combinations thereof.
摘要:
A thermoplastic vulcanizate (TPV) from a blend of a first thermoplastic polyolefin, a second thermoplastic olefin and a rubber is described. The rubber is crosslinked with a hydrosilylation crosslinking agent. The second polyolefin includes at least one OR group pendant to a Si atom chemically attached via one or more intermediate molecules to said second polyolefin. R can be hydrogen or an alkyl of 1 to 8 carbon atoms. The OR groups can react with the hydrosilylation catalyst to reduce the compression set of the TPV.
摘要:
A thermoplastic elastomer composition has a plastic phase or matrix of an engineering thermoplastic such as a polyamide and a crosslinked phase of cured acrylic rubbers. The rubbers contain at least two functionalized acrylic rubbers wherein the functional group such as a carboxyl, an epoxy, or a hydroxyl can be the same or different. The curing agents generally react via covalent bonding with the reactive functional groups of the rubbers. The composition can be dynamically vulcanized and when one of the rubbers is a terpolymer of ethylene-alkyl acrylate-unsaturated carboxylic acid, the composition has a single low temperature brittle point.
摘要:
A thermoplastic elastomer composition has a plastic phase or matrix of an engineering thermoplastic such as an ester polymer and a crosslinked phase of cured acrylic rubbers. The rubbers are cured by a curing agent and contain at least two functionalized acrylic rubbers wherein the functional group such as a carboxyl, an epoxy, or a hydroxyl can be the same or different. The composition can be dynamically vulcanized and desirably when one of the functionalized acrylic rubbers is a terpolymer of ethylene-alkyl acrylate-unsaturated carboxylic acid, the composition has a single low temperature brittle point.
摘要:
Shaped articles are made from blends of rubber and plastic in which the rubber is in the form of discrete vulcanized particles dispersed in the plastic. After shaping the articles, they are exposed to free-radical crosslinking which converts the blends from thermoplastics to thermosets.
摘要:
Random thermoplastic ethylene copolymers can be used to increase the elongation to break and toughness of thermoplastic vulcanizates. Polypropylene is a preferred thermoplastic phase. The rubber can be olefinic rubbers. Random thermoplastic ethylene copolymers are different from Ziegler-Natta ethylene copolymers as the compositional heterogeneity of the copolymer is greater with Ziegler-Natta copolymers. This difference results in substantial differences in properties (elongation to break and toughness) between thermoplastic vulcanizates modified with random thermoplastic ethylene and those modified with Ziegler-Natta ethylene copolymers. An increase in elongation to break results in greater extensibility in the articles made from a thermoplastic vulcanizate.
摘要:
Low oil swell, non sticky readily processable carboxylated nitrile rubber-thermoplastic polyurethane vulcanizate compositions have increased upper service temperature over comparable thermoplastic polyurethanes. The compositions of the present invention are made utilizing a processing aid, for example, maleated polyolefins and addition type curing agents such as bisoxazolines or bisimidazolines. The compositions generally contain thermoplastic polyurethane as a continuous phase with the carboxylated nitrile rubber being dispersed therein.