Ionic graft copolymerization. VII. Ionic graft copolymerization of β‐propiolactone onto the trunk polymers containing pyridine, amide, sulfonyl chloride, and carboxylic acid anhydride groups

Abstract

AbstractThe graft copolymerization of β‐propiolactone (βPL) onto the various trunk polymers containing polar substituents such as pyridine, amide, sulfonyl chloride, and carboxylic acid anhydride groups was carried out. In the grafting onto the basic trunk polymer containing 4‐vinylpyriding units, two kinds of grafting mechanism are supposed. In the case of rigorously dried trunk polymer, the polymerization is initiated by betaine and proceeds with higher grafting efficiency. Another is initiated by pyridinium hydroxide and proceeds with lower grafting efficiency. Another is initiated by pyridinium hydroxide and proceeds with lower grafting efficiency in the presence of some amount of water. With acidic trunk polymer containing sulfonyl chloride groups, no graft copolymer was produced. The grafting efficiency of βPL onto the amphoteric trunk polymer containing acrylamide units was found to be between those of basic and acidic trunk polymer. In addition, the grafting by means of ionic copolymerization of βPL with maleic anhydride units contained in trunk polymer proceeded with very high grafting efficiency.