Abstract: The invention relates to new plastic materials made of heterogeneous copolymers of vinylidene fluoride and chlorotrifluoroethylene, consisting of elastomeric nodules of heterogeneous copolymers of vinylidene fluoride and chlorotrifluoroethylene which are dispersed in a crystalline continuous phase of quasi vinylidene fluoride polymer.According to another feature, the plastic materials are made of heterogeneous copolymers containing overall approximately from 10 to 22% by weight of CTFE and exhibiting a melting temperature of at least 165.degree. C. and a flexural elasticity modulus of not more than 1000 MPa. The heterogeneous copolymers are obtained by a radical copolymerisation in aqueous medium, all of the comonomers being introduced at the beginning of the copolymerisation.The plastic materials can be employed for the manufacture of flexible articles such as flexible tubular articles, sheathing for cables, coatings and films.