Enzymatic Degradation of Polycarbonates: Response Surface Methodology (RSM) Based Approach

Abstract

Abstract Polycarbonate is a tough polymer known for its extreme toughness, inertness and transparency and is considered to be chemically resistant. Polycarbonates are susceptible to photo degradation and thermal degradation. The mechanism followed in the degradation of similar polymeric compounds is found to be mostly hydrolysis reactions. Reactions of Bisphenol A polycarbonate with the lipase Candida rugosa were carried out over a period of 72 hours at different temperatures ranging from 25 oC to 65 oC and at different lipase activities of 400 U/ml, 800 U/ml, 1200 U/ml and 1600 U/ml. The weight loss of polycarbonate was studied against various factors. It is found that there is a rapid loss of polycarbonate around the time period above 48 hrs and at the temperature 55 oC for above enzyme activities. The supernatant was subjected to FTIR and the presence of the Bisphenol A, a monomer was found. The results were subjected to the statistical tool, Design of Experiments, in which the fitness of the results were statistically analyzed and the interactions between the parameters studied. The Response surface methodology (RSM) and the ANOVA analysis were performed on the experimental data and the parameters were found to be non interactive. The model equation for the degradation kinetics is obtained from the coefficients of the ANOVA analysis and the fitness of the model data with the actual obtained experimental data is found to be close and similar over the parameters