METHOD FOR PRODUCTION OF ELASTOMER FLUORINATED COPOLYMERS Russian patent published in 1997 - IPC

FIELD: production of elastomer fluorinated copolymers. SUBSTANCE: elastomer fluorinated copolymers comprising iodine atom in tail place of copolymer are prepared by copolymerization of vinylidene chloride and at least one comonomer which is chosen of tetrafluoroethylene, hexafluoropropylene and perfluoroalkyl vinyl ether. The process is carried out in the presence of initiator of radical type, bromine-containing monomer to be polymerize and iodine compound. Iodide of alkali metal which is chosen of lithium chloride, sodium chloride and potassium chloride is used as mentioned above iodine compound, its quantity being 0.008-0.46 moles per 100 moles of monomer. Perfluorobromomethyl- or perfluorobromomethyl vinyl ether is used as mentioned above bromine-containing monomer, its quantity being 0.097-0.277 moles per 100 moles of monomer. Said bromine-containing monomer and iodine compound are portionwise fed into polymerized mixture, the process is carried out within the whole period of the process. Quantity of vinylidene chloride, tetrafluoroethylene and hexafluoropropylene are 46-79 mol %, 21-26 mol % and 5-25 mol % respectively, quantity of perfluoroalkyl vinyl ether is not more than 23% of summary amount of monomers. Copolymers are easily affected by vulcanization, they have improves processing features and are stable at heat attack. EFFECT: improved efficiency of the method, improved processing features of desired copolymers. 2 cl, 2 tbl