Patent ID: 6015858
Filing Date: 2000-01-18
Classification: C08F,C08G,C08L

Abstract:
A method for preparing a thermoplastic elastomer, said method comprising:(I) reacting(A) a fluorocarbon resin with(B) a grafting agent selected from the group consisting of(B') an organic compound which contains at least 2 olefinic groups,(B"") a organopolysiloxane having a viscosity of less than 5,000 mPa-s at 25.degree. C. and containing at least 2 olefin groups and(B'"") a silane having at least one olefinic group and at least one silicon-bonded moiety selected from the group consisting of a hydrolyzable group and a hydroxyl group, in the presence of(C) a radical initiator,to prepare a modified fluorocarbon resin;(II) mixing said modified fluorocarbon resin with(D) a silicone base comprising(D') a diorganopolysiloxane having a plasticity of at least 30 and having an average of at least 2 alkenyl radicals in its molecule and(D"") 10 to 200 parts by weight of a reinforcing filler for each 100 parts by weight of said diorganopolysiloxane (D'),(E) an organohydrido silicon compound which contains an average of at least 2-silicon-bonded hydrogen groups in its molecule, and(F) a hydrosilation catalyst,components (E) and (F) being present in an amount sufficient to cure said diorganopolysiloxane; and(III) dynamically curing said diorganopolysiloxane,wherein the amount of said diorganopolysiloxane base (B) used is such that at least one property of said thermoplastic elastomer selected from tensile strength or elongation is at least 25% greater than the respective property for a corresponding composition wherein said fluorocarbon resin is not modified,with the proviso that said thermoplastic elastomer has an elongation of at least 25%.