| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for continuously producing a polyvinylidene fluoride (PVDF) homopolymer or copolymer, wherein comonomer is selected from compounds containing polymerizable vinyl capable of being activated by the action of free radicals, the comonomer has at least one fluorine atom, fluoroalkyl or fluoroalkoxy directly bonded to the vinyl and the ratio of the comonomer is 0-50 wt.%. SOLUTION: The method for continuously producing PVDF homopolymer or copolymer comprises (a) introducing 1,1-difluoroethylene (VF2), comonomer of an optional component and a radical initiator into a reactor keeping pressure at 300-3,000 bar, (b) taking out the reaction mixture from the reactor of (a) stage and feeding the mixture into a separator, (c) recovering the molten PVDF into the separator and continuously taking out and (d) recovering VF2 and the comonomer of the optional component and recycling to (a) stage. The oxygen content of the VF2 introduced in the (a) stage and the remaining VF2 for recycling is kept≤5 ppm. COPYRIGHT: (C)2004,JPO
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