Novel in situ crosslinking reaction of ethylene-vinyl alcohol copolymers by propylene carbonate

The gel content, crystallization and melting behavior, tensile strength, and thermal stability of crosslinked ethylene-vinyl alcohol copolymer (EVOH) with propylene carbonate were investigated using modulated differential scanning calorimetry (MDSC), tensile tester, differential thermal analysis/thermal gravimetric analysis (DTA/TGA), respectively. The crosslinking process was believed to be resulted from the ester-exchange reaction between propylene carbonate and EVOH. Increasing propylene carbonate content resulted in the increase of gel content and tensile strength of crosslinked EVOH, and the decrease of elongation at break. However, increasing propylene carbonate content decreased the melting temperature, crystallization temperature, and crystallinity. The resulting crosslinked EVOH exhibited a higher thermal decomposition temperature than neat EVOH.