EVALUATION OF NATURAL FLAVONOIDS AS CROSSLINKING AGENTS FOR POLYVINYL ALCOHOL

摘要

Anthocyanins have been chosen as natural crosslinking agents for polyvinyl alcohol (PVOH). Tosylation of secondary hydroxyl functionality in PVOH was carried out with p-toluenesulfonyl chloride in the presence of bases. The structures of the crosslinked PVOH and the crosslinking mechanism were established from their 'H NMR spectral. Hydroxyl contents in PVOH decreased due to the crosslinking of tosylated PVOH with anthocyanin. It was also found that crosslinking of PVOH by anthocyanin enhanced the mechanical properties of PVOH film.