Abstract: A tapered stepped land having a choked funnel section which terminates in a lateral longitudinal section results in the formation of a foamed extrudate of a vulcanized blend of polyolefin and rubber which is a mass of closed cells having a specific gravity in the range from about 0.1 to 0.5 and the cells are sheathed in a dense non-porous, smoothly continuous skin which is formed integrally with the extrudate. The dense skin makes it possible to deposit a thin slip-coating of a low friction material longitudinally upon a chosen portion of the surface. An extruded weatherseal for the glass of an automobile's window has the slip-coating deposited as a thin film on a contacting strip of a surface which is in contact with the glass.

Abstract: A polar thermoplastic and acrylate or ethylene acrylate based polar rubbers form a useful thermoplastic vulcanizate when the rubber is selectively cured with curatives which do not affect the polar thermoplastic and do not generate volatile organics. Examples of thermoplastics include aromatic polyesters, polycarbonates, poly(phenylene oxide), or combinations thereof. Examples of curatives include compounds with a multifunctional oxazoline, oxazine or imidazoline, which can react with functional groups such as carboxylic acid groups on the rubber.

Abstract: The invention relates to a method of high frequency welding of non-polar thermoplastic elastomers characterized in that said elastomers comprise a polar modifier. Furthermore, the invention relates to shaped articles obtainable by said method.

Abstract: Thermoplastic elastomers having improved low temperature properties are provided by incorporating suitable low molecular weight ester plasticizer into blends of crystalline polyolefin homopolymer or copolymer and olefinic rubber. The rubber component of the composition is at least partially cured.

Abstract: Random propylene thermoplastic copolymers can be used to increase the elongation to break and toughness of thermoplastic vulcanizates. Semi-crystalline polypropylene is a preferred thermoplastic phase. The rubber can be olefinic rubbers. Random thermoplastic polypropylene copolymers are different from conventional Ziegler-Natta propylene 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 propylene copolymers and those modified with conventional Ziegler-Natta propylene copolymers. An increase in elongation to break results in greater extensibility in the articles made from a thermoplastic vulcanizate.

Abstract: The present invention relates to a curable composition comprising a thermoplastic polyolefin resin and a curable star-branched rubber, a thermoplastic elastomeric vulcanizate obtainable therefrom by dynamically vulcanizing said curable composition in the presence of a suitable curative and shaped articles comprising said vulcanizate.

Abstract: In the preparation of thermoplastic elastomers by hydrosilylation crosslinking of the elastomeric component, the use of an elastomer containing a non-conjugated diene and having a Mooney viscosity within the MST range of 45 to 100 provides products with a high level of crosslinking and an improved combination of physical properties. This improvement is obtained even at low concentrations of hydrosilylation catalyst.

Abstract: 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.

Abstract: 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.

Abstract: Thermoplastic vulcanizates are described which include a carbonyl containing or carbonyl functionalized rubber crosslinked with a hydrosilylation crosslinking agent activated with a platinum containing catalyst. The carbonyl containing or carbonyl functionalized rubber facilitates making thermoplastic vulcanizates with higher lubricity, better contact clarity and alternative surface properties.

Abstract: An improved process for the preparation of thermoplastic elastomers by hydrosilylation crosslinking, in which a hydrosilylation crosslinking agent with a low degree of polymerization and/or a hydrosilylation crosslinking agent diluted in oil is used.

Abstract: An improved process for the preparation of thermoplastic elastomers by hydrosilylation crosslinking of a butyl rubber component, in which a platinum containing hydrosilylation catalyst is used. The butyl rubber component includes a copolymer of at least isobutylene and an aromatic divinyl compound such as divinylbenzene. The copolymer of at least isobutylene and divinylbenzene is significantly easier to crosslink into a substantially insoluble rubber in a thermoplastic vulcanizate than isobutylene copolymers with only unsaturated repeating units from conjugated dienes. A crosslinked rubber component is obtained in the thermoplastic elastomer composition.

Abstract: 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.

Abstract: Thermoplastic vulcanizate blends are prepared from a semi-crystalline polymer and a rubbery copolymer derived from copolymerizing at least one alpha-olefin monomer and at least one cyclic olefin copolymer. The rubbery copolymer also includes repeat units from at least one polyene monomer. The polyene monomer provides residual unsaturation for crosslinking of said rubbery copolymer. Crosslinking the rubbery copolymer of the blend generally reduces tension set, compression set and oil swell in aliphatic solvents. The cyclic olefin monomer reduces oil swell in aliphatic oils.

Abstract: A blend of a semicrystalline polyolefin, a rubbery polymer containing repeat units from norbornene, and a polymeric compatibilizer is disclosed. This composition has reduced oil swell as compared to thermoplastic vulcanizates from a semicrystalline polyolefin and hydrocarbon rubbers.

Abstract: An improved process for the preparation of thermoplastic vulcanizates from butyl rubbers by hydrosilylation crosslinking of acrylic or alkacrylic functionalized copolymers of isobutylene and paramethylstyrene is disclosed. The functionalization results in lower compression and tension set than when using conventional butyl rubbers. Other physical properties of the thermoplastic vulcanizate are improved consistent with more efficient crosslinking of the functionalized copolymer.

Abstract: The present invention relates to new block copolymers of chemically modified polyolefins and thermoplastic polyurethanes, copolyesters or copolyamides a method for the preparation of said block copolymers and their use for compatibilizing blends of polar and non-polar thermoplastic elastomers. The block copolymers according to the present invention can further be used for promoting the adhesion of thermoplastic elastomers onto various polar engineering resins.

Abstract: Desirable thermoplastic vulcanizates can be prepared from a polar engineering thermoplastic; a halogenated copolymer of p-alkylstyrene and an isomonoolefin having from 4 to 7 carbon atoms; and either an ethylene rubbery polymer or a diene based rubbery polymer or combinations thereof. The ethylene rubbery polymer desirably has at least one pendant carboxylic acid group, amine group, epoxy group, hydroxyl group or an anhydride of two carboxylic acid groups or combinations thereof. Desirable diene based rubbery polymers include epoxidized natural rubber and epoxidized homopolymers and copolymers of dienes.

Abstract: Low oil swell, processable carboxylated nitrile rubber thermoplastic vulcanizate compositions having high melting points are made utilizing a processing aid, for example, maleated polyethylene, and addition type curing agents such as bisoxazolines or bisimidazolines. The compositions generally contain polar thermoplastic high melting point crystalline polymers such as polyester as a continuous phase with the carboxylated nitrile rubber being dispersed therein.

Abstract: Dynamic vulcanizates of an engineering thermoplastic ("plastic"), e.g. a polyamide or polyester, with acrylate rubbers having dissimilar functional groups are prepared with a metal fatty acid salt in the absence of a conventional curative, provided the rubbers are molecularly intermixed. An acrylate rubber with halogen functionality ("AcrRubHal") is thus crosslinked in a single mixing stage with an acrylate rubber having carboxyl, hydroxyl or epoxy functionality ("AcrRubX") in a "plastic". Quaternary ammonium salts and tertiary amines do not function as curatives, as one might expect. But a metal fatty acid salt, preferably a metal stearate or oleate and concentrates thereof effectively crosslink the rubbers. TPVs produced without conventional curing agents are relatively "soft", but have highly desirable low temperature physical properties and oil resistance.