Water contact angle and FTIR study of the surface modification of PET by lipolytic enzymes.

The goal of this study was to investigate the interaction of a lypolytic enzyme with poly-(ethylene terephthalate) (PET). Chemical, physical and structural changes induced on PET substrates with different degree of crystallinity were systematically investigated by water contact angle measurements and FTIR-ATR analyses. Treatment of PET with a commercial cutinase resulted in increased hydrophylicity and improved wettability of the PET materials. Water contact angle measurements indicate that cutinase displayed higher hydrolytic activity towards less crystalline PET. FTIR-ATR allowed to elucidate some chemical and structural features of the enzymatically-modified PET surface and provided some insight into the mechanism of the interaction of the lypolytic enzyme with PET