Characterisation of beta-chitin/poly(vinyl alcohol) blend films

Blend films of beta-chitin (derived from squid pens) and poly(vinyl alcohol) (PVA) were prepared by a solution casting technique from corresponding solutions of beta-chitin and PVA in concentrated formic acid. Upon evaporation of the solvent, films prepared from pure beta-chitin and pure PVA were found to be transparent, while the film having 50/50 composition was found to be cloudy. Miscibility of the polymers in the amorphous phase of the films at various compositions was assessed using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM) techniques. The glass transition temperature of the blend films was found to increase slightly with an increase in the beta-chitin content. The effect of blend compositions on apparent degree of crystallinity, mechanical properties, and swelling behavior of the as-prepared blend films was also investigated. (C) 2002 Elsevier Science Ltd. All rights reserved.