DETERMINATION OF CRYSTALLINITY OF SWOLLEN POLYVINYL-ALCOHOL) BY LASER RAMAN-SPECTROSCOPY

In the reported experiments, laser Raman spectra of atactic poly(vinyl alcohol) (PVA) after heat treatment and/or swelling in water have been obtained. An amorphous Raman band is observed at 1124 cm** minus **1, while a crystalline Raman band is found at 1147 cm** minus **1. A new method for crystallinity determination is proposed, in which the amorphous band is used instead of the crystalline band. The method is superior to others for water-swollen PVA samples. Laser Raman spectra of swollen PVA revealed that swelling causes destruction of a major fraction of the crystalline regions and the remaning intact crystalline part increases with increasing temperature of heat treatment.