Mfg. fluoro-polymer contg. carboxy gps.

摘要

A fluoro polymer (I) contg. COOH gps. is prepd. by reacting (a) a fluoropolymer contg. OH gps., in (b) an organic solvent with (c) an anhydride of a dibasic acid of formula (II) where R is a divalent organic gp., with conversion of at least part of the OH gps.into ester gps. of formula -O-CO-RCOOH.Component (a) is esp. a copolymer of a fluoroolefine, partic. of tetrafluoroethylene or chloro-trifluoroethylene, with an alkyl vinyl ether. The OH gps. may be derived from an unsatd. comonomer contg. OH gps., esp. a hydroxyalkyl vinyl ether. A pref. copolymer contains fluoroolefin, cyclohexyl vinyl ether, alkyl vinyl ether, and hydroxy vinyl ether in molar ratio of 40-60:5-45:5-45:3-15 (45-55:10-30:10-35:5-13).(I) can be used in lacquers. (I) is obtd. in good yield in a 1-stage reaction. Hydrophilic properties can be improved, or cross linking positions or ion-exchange gps. can be introduced. Hard, flexible glossy coatings, resistant to solvents, soiling and weather, can be obtd