Enhanced enzymatic degradation in nanocomposites of various organically-modified layered zinc phenylphosphonates and poly (butylene succinate-co-adipate)

In this work, two long-chain alkylamines, dodecylamine (DDA) and octadecylamine (ODA), intercalated with layered zinc phenylphosphonates (PPZns) were prepared using a simple chemical intercalation method. Both biocompatible poly(butylene succinate-co-adipate) (PBSA)/organically-modified PPZn nanocomposites fabricated by a melt-mixing technique have been characterized by wide-angle X-ray diffraction (WAXD) and transmission electron microscopy (TEM). These results indicated that the stacking layers of the ODA-PPZn in the PBSA matrix were fully/partially exfoliated and the intercalated PBSA/DDA-PPZn nanocomposites were formed. Enzymatic degradation tests using Lipase from Pseudomonas sp. as the enzyme was investigated. The weight loss of PBSA increases with an increase in the content of organically-modified PPZn. The degradation rate of all samples varied in the order PBSA/ODA-PPZn nanocomposites > PBSA/DDA-PPZn nanocomposites > neat PBSA. This result is probably due to the lowest degree of crystallinity for PBSA/ODA-PPZn nanocomposites. The degradation behavior of the neat PBSA belongs to exo-type hydrolysis activity due to the degradation starts from both ends of the polymer chains.