Abstract: A fluoroelastomer (A) based on vinylidene fluoride (40-83% by moles), perfluoropropene (15-35%) and tetrafluoroethylene (0%-30%) and a diamino compound (B), are mixed with a copolymer (C) containing tetrafluoroethylene (40%-60% by moles) and propylene (60-40%).The thus obtained mixture is covulcanizable with systems based on organic peroxides. In particular mixtures are employed, containing: (A)=42-70% by weight, (B)=1-4%, (C)=51-22%, peroxide 0.4-5%, triallylisocianurate 2-4%.

Abstract: Vulcanizable mixes based on elastomeric copolymers of vinylidene fluoride with fluorinated or chlorofluorinated olefins, or with fluorinated vinyl ethers, and which comprise, as processing aid, at least one fluorinated polyamide, are disclosed.

Abstract: A process for preparing new elastomeric copolymers of vinylidene fluoride having exceptionally valuable properties is disclosed. Monomeric mixtures containing vinylidene fluoride in such quantities as to yield elastomeric products are polymerized in solution, emulsion or suspension, or in the absence of solvents and/or dispersants (mass or bulk) in the presence of radical polymerization initiators, at temperatures of -30.degree. C to =200.degree. C, preferably at 0.degree. C to 120.degree. C, and at a pressure of from autonomous pressure to 300 atmospheres. In this process, vinylidene fluoride is fed into the reaction mixture during the polymerization and in a quantity such that the ratio between the added vinylidene fluoride and the vinylidene fluoride of the monomeric mixture subjected to polymerization varies between 0.1 and 1.5.