| 摘要 |
PROBLEM TO BE SOLVED: To obtain a copolymer containing carboxy groups safely and inexpensively by treating a vinylidene fluoride copolymer with a base and a peroxide preferably in the presence of a phase transfer catalyst. SOLUTION: A copolymer containing carboxy groups is obtained by dissolving 100 pts.wt. of a copolymer such as a vinylidene fluoride-hexafluoroporpene copolymer or the like to an organic solvent such as a ketone or the like, reacting it with 0.3-50 wt.% of sodium hydroxide and 5-50 wt.%, against the produced double bond, of hydrogen peroxide for 3-24 hr in the presence of 1-10 pts.wt. of a phase transfer catalyst of the formula: (R1 R2 R3 R4 N)<+> X<-> (wherein each of R1 to R4 in the formula independently stands for a 1-25C alkyl or the like; and X<-> is an anion such as Cl<-> , HSO4 <-> or the like) such as tetramethylammonium bromide or the like, and then adding a sulfite or the like to control the pH. The original vinylidene fluoride copolymer contains 30-85 mol.% of vinyidene fluoride and has a weight average molecular weight of 1×10<5> -9×10<5> , a number average molecular weight of 0.5×10<5> -6×10<5> and a Mooney viscosity of 5-200. |
