Cross-linking of polyvinyl alcohol/starch blends by epoxy silane for improvement in thermal and mechanical properties

Abstract

Effects of cross-linking were examined for polyvinyl alcohol, starch, and their blends. The blends were prepared using various compositions of pure starch, pure polyvinyl alcohol (PVOH), and a combination of both starch and polyvinyl alcohol. The cross-linker used for this study was epoxy silane. The blends were tested against the canarium wood substrate for tensile strength. Further properties, such as viscosity and wet tack, were also evaluated. Analytical tests such as differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) demonstrated the phenomenon of cross-linking, having shown an increase in glass transition temperature (Tg) and area under the curve of tan delta. The efficient and novel cross-linking of hydroxyl groups present in the starch and PVOH contributed to better adhesion on the wood substrate and also better cohesion between the chains.