Enzyme catalysed degradation of polyester fibres – A comparative study between poly(ethylene terephthalate) and poly(butylene adipate-co-terephthalate)

Enzyme catalysed hydrolysis provides an environmentally friendly route for controlled decomposition of polyester fibres. In this work, the hydrolysis of polyethylene terephthalate (PET) and polybutylene adipate terephthalate (PBAT) by using a cutinase from Humicola insolens (HiC) was compared with the aim, to better understand the relationship between the polymer structure and the enzyme catalysed degradation. PBAT exhibited much higher sensitivity to hydrolysis most likely due to the presence of the longer carbon chain diol and of aliphatic adipic acid in addition to terephthalic acid. In addition, the higher degree of crystallinity of PET restricts the attack of the enzyme and preserves the high order the fibres during the hydrolysis. The results provide further basis for the optimisation of enzyme catalysed hydrolysis and polymer degradation processes of polyester fibres.