Properties of mixtures of silk fibroin/syndiotactic‐rich poly(vinyl alcohol)

Abstract

Abstract The gelation of mixed solutions of silk fibroin (SF)/syndiotactic‐rich poly(vinyl alcohol) ( s ‐PVA), the thermal analysis of dry‐gels, and the various properties of blend films were investigated. The rate of gelation of a mixed solution was lower than that of each SF or s ‐PVA solution of the same concentration. In the DSC thermograph of mixed dry‐gel (SF/ s ‐PVA = 2/8–8/2) 2 endothermic peaks corresponding to SF (at 288–299°C: decomposition) and s ‐PVA (at 233–241°C: melting) were found. Namely, microphase segregation took place. This was confirmed by optical and electron microscopes. The mechanical properties of blend films did not have additive properties. The degree of swelling in water of blend films was independent on water temperature or methanol treatment. The mechanochemical behaviors were barely observed by the pH exchange between pH 2 and 12 only under lower loads. The addition of SF into s ‐PVA films promoted the permeation of neutral salts.