Enzymatic degradation behaviors and kinetics of bio-degradable jute/poly (lactic acid) (PLA) composites

The jute fiber reinforced poly (lactic acid) (PLA) composite renders a complete bio-degradable characteristic with relative remarkable mechanical properties, while it is strongly sensitive to the enzyme environments. To elaborate the enzymatic degradation mechanism of the jute/PLA composites, this study performed a 35 days degradation in an enzyme solution containing protease K, cellulase, ligninase, and pectinase. The changes of water absorption, crystallinity, molecular weight, morphologies, chemical compositions during enzymatic degradation were experimentally evaluated. We divided the total degradation process into three stages according to the primary degradation targets: the macromolecular chains of PLA, the fiber-matrix interfaces, and the jute fiber. The degradation kinetics was proposed based on the Michaelis-Menten kinetics approach. The elucidation of enzymatic degradation mechanisms of jute/PLA composite is meaningful for improving the application prospects of the bio-degradable green materials.