Abstract: A thermoplastic elastomer composition comprising a blend of (A) thermoplastic materials comprising (A1) a polyamide block copolymer and (A2) one or more thermoplastic organic polymers excluding (A1), with (B) a silicone composition comprising (B1) a silicone base comprising (B1a) a diorganopolysiloxane polymer having a viscosity of at least 1000000 mPa·s at 25° C. and an average of at least 2 alkenyl groups per molecule, (B1b) a reinforcing filler in an amount of from 1 to 50% by weight of polymer (B1a), and (B2) an organohydrido silicone compound which contains an average of at least 2 silicon-bonded hydrogen groups per molecule, (C) a hydrosilylation catalyst, which composition may additionally optionally comprise (D) one or more additives; wherein the weight ratio (A):(B) is in the range 50:50 to 95:5, and wherein component B2 and C being present in an amount sufficient to cure said silicone composition B.

Abstract: Thermoplastic silicone elastomer compositions are disclosed. The thermoplastic elastomer compositions comprise a blend of an organic thermoplastic elastomer and a silicone composition. A process for forming a vulcanized thermoplastic elastomer composition is also disclosed. The thermoplastic elastomer compositions can be used to form functional and/or aesthetic automotive parts such as gear knobs, seat belt connectors, interior mats, airbag protective covers, and over-molded skins for dash boards and armrests; to form appliance parts; to form soft-feel grips for hand held devices; and to form medical devices, sporting goods and general rubber parts. The thermoplastic elastomer compositions provide durable aesthetics, haptic and ergonomic properties along with stability to most commonly used chemicals and high mechanical performance, abrasion and scratch resistance.

Abstract: The invention relates to thermoplastic elastomer compositions comprising a blend of a thermoplastic urethane polymer and a silicone composition, and to a process for forming a vulcanized thermoplastic elastomer composition. The thermoplastic elastomer composition comprises a blend of a thermoplastic organic polymer comprising a urethane polymer and (B) a silicone composition comprising (B1) a silicone base comprising (B1a) a diorganopolysiloxane gum having an average of at least 2 alkenyl groups per molecule and (B1b) from 1 to 50% by weight based on the diorganopolysiloxane gum (B1a) of a reinforcing filler, and (B2) an organohydrido silicone compound which contains an average of at least 2 silicon-bonded hydrogen groups per molecule, wherein the weight ratio of the thermoplastic organic polymer (A) to the silicone composition (B) is in the range 55:45 to 80:20.

Abstract: A process for increasing the scratch resistance of a composition comprising a thermoplastic organic polymer and a scratch resistant polymer composition per se. The process for increasing the scratch resistance of a composition comprising a thermoplastic organic polymer (P) comprises reactively mixing a thermoplastic organic polymer (A) and an organopolysiloxane (B) in a first step (I) at a temperature at which the thermoplastic organic polymer (A) and the organopolysiloxane (B) are in liquid phases to form a masterbatch. The organopolysiloxane (B) contains at least one functionality capable of reacting with the thermoplastic organic polymer (A) so that a copolymer of components (A) and (B) is formed in the masterbatch during the reactive mixing. The process further comprises a second step (II) of mixing the masterbatch with the composition comprising the thermoplastic organic polymer (P).

Abstract: A process for the production of a polymer composition is disclosed. The polymer composition comprises an organopolysiloxane dispersed in a thermoplastic organic polymer liable to thermo-radical degradation or cross-linking when subjected to a high compounding energy at a temperature above its melting point. In a first step (I), a thermoplastic organic polymer and an organopolysiloxane are mixed at a temperature at which both the thermoplastic organic polymer and the organopolysiloxane are in liquid phases to form a masterbatch. In a second step (II), the masterbatch is mixed with further thermoplastic organic polymer to form a polymer composition having a lower concentration of organopolysiloxane than that in the masterbatch. In the first step (I), the thermoplastic organic polymer and the organopolysiloxane are mixed in the presence of an additive capable of inhibiting the thermo-radical degradation or cross-linking of the thermoplastic organic polymer.

Abstract: A process of obtaining a thermoplastic composition formed from a polyolefin matrix is disclosed. The polyoelfin matrix comprises a polypropylene The process comprises (a) the formation of a viscoelastic mixture of the polypropylene and the lamellar mineral by heating and kneading the composition at a temperature at least equal to the working temperature of the polypropylene, (b) submitting the viscoelastic mixture to thermo-mechanical work, (c) eliminating volatile components from the viscoelastic mixture, and (d) transforming the viscoelastic mixture resulting from step (c) into a granulated material. The viscoelastic mixture is subjected during steps (a) and (b) to a weak and controlled rate of shearing of no more than 200 s?1 and the viscoelastic mixture is subjected in step (b) to at least one cycle of extension and relaxation in a dedicated zone which is at least 25% of the total length of at least one screw of a compounding extruder.

Abstract: A partly cross-linked thermoplastic elastomer polyolefin composition intended to be converted by any plastics processing technique into a molded part, such as a cover for housing a vehicle's safety airbag, comprises an olefin polymer of polypropylene type, at least one copolymer of ethylene-alpha-olefin type, at least one cross-linking agent and a free radicals formation agent characterized in that a) the olefin polymer of polypropylene type is chosen from the group of polypropylene/ethylene or polypropylene/?-olefin copolymers and selected from those having an impact resistance of at least 40 kJ/m2 when measured using the notched Izod impact resistance test at 23° C. in accordance with ISO standard 180. b) at least one copolymer of the ethylene-?-olefin type is selected from the group formed by those having a density at least equal to 0.870 g/cm3 in accordance with ISO standard 1183. c) at least one thermoplastic elastomer is introduced into the composition.

Abstract: The invention concerns a partly cross-linked thermoplastic elastomer polyolefin composition intended to be converted by any plastics processing technique, but by injection in particular, into a moulded part, such as, for example, a cover for housing a vehicle's safety airbag, comprising an olefin polymer of polypropylene type, at least one copolymer of ethylene-?-olefin type, at least one cross-linking agent and a free radicals formation agent characterised in that a) the olefin polymer of polypropylene type is chosen from the group of polypropylene/ethylene or polypropylene/?-olefin copolymers and selected from those having an impact resistance of at least 40 kJ/m2 when measured using the notched Izod impact resistance test at 23° C. in accordance with ISO standard 180. b) at least one copolymer of the ethylene-?-olefin type is selected from the group formed by those having a density at least equal to 0.870 g/cm3 in accordance with ISO standard 1183.