摘要 |
New blends of fluorinated thermoplastic elastomers are disclosed that contain a two-phase composition including a continuous phase of a melt processible crystalline thermoplastic fluorocarbon resin and a dispersed phase of an amorphous crosslinked fluoroelastomer, and a dispersion-process-produced, non-fibrillating, non-melt-processible polytetrafluoroethylene (PTFE) powder. The PTFE copolymer is made up of recurring units of hexafluoropropylene, perfluoro(alkyl vinyl ether) wherein the alkyl group has 1-4 carbon atoms, and mixtures thereof. The PTFE compounds uniformly with the two-phase composition without forming visible agglomerates. Poly(phenylene sulfide) powder can be added to the blend to increase melt flow characteristics. Additionally, an uncured fluoroelastomer can be incorporated into the blend to enhance its mechanical properties. The preparation of the fluorinated thermoplastic elastomers involves dynamic curing of the fluoroelastomer in the presence of the molten thermoplastic fluorocarbon resin and the non-melt-processible PTFE resin.
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