VINYLIDENE FLUORIDE POLYMER AND PROCESS FOR PRODUCING THE SAME

摘要

One or more monomers comprising vinylidene fluoride as the main ingredient are fed to a polymerization system containing a polymerization initiator to conduct suspension polymerization, the monomers being fed portion-wise at a pressure lower than the critical pressure Pcr (=4.38 MPa) for vinylidene fluoride and at a pressure not lower than Pcr. Thus, a vinylidene fluoride polymer which has excellent high-temperature discoloration resistance and is significantly reduced in the release of organic substances and ionic components can be produced without the need of a labor and cost for the recovery of a special halogenated hydrocarbon solvent used in a large amount.