Journal of Polymer Science Part A: Polymer Chemistry, Vol.37, No.14, 2581-2585, 1999
Comparison of the catalytic activity of PHB-depolymerase, yeast lipase, and papain on poly(ethylene adipate), poly(ethylene succinate), and poly (3-hydroxybutyric acid)-co-(3-hydroxyvaleric acid)
PHB-depolymerase degraded poly[(3-hydroxybutyric acid)-co-(3-hydroxyvaleric acid)] (PHB/V) significantly. No other enzyme used in this study showed activity toward PHB/V. Weight loss and gel permeation chromatography (GPC) studies suggested that enzymatic degradation takes place by a surface erosion mechanism. pH studies demonstrated that enzymatic degradation occurs even when little weight loss is observed. Differential scanning calorimetry (DSC) analysis demonstrated that the enzymes studied prefer to degrade amorphous regions.