Enzymatic degradation processes of poly[(R)-3-hydroxybutyric acid] and poly[(R)-3-hydroxybutyric acid-co-(R)-3-hydroxyvaleric acid] single crystals revealed by atomic force microscopy: effects of molecular weight and second-monomer composition on erosion rates.

摘要: Enzymatic degradation processes of poly[(R)-3-hydroxybutyric acid] (P(3HB)) and acid-co-(R)-3-hydroxyvaleric (P(3HB-co-3HV)) single crystals in the presence PHB depolymerase from Ralstonia pickettii T1 were studied by real-time static atomic force microscopy (AFM) observations. Fibril-like generated along long axis during enzymatic degradation, then dimensions fibril-like analyzed quantitatively. The morphologies sizes dependent on molecular weight copolymer composition polymers. For all samples, crystalline thickness gradually decreased toward a tip root crystal after for 1 h. thinning may be attributed to destruction chain-packing structure crystallographic c adsorption enzyme. From AFM images, it was found that at initial stage erosion started disordered region form grooves axis. deformed constant rate with induction time. increased decrease an increase composition. On other hand, axis, crystal, only composition, value governed both rates crystals. In addition, we able estimated overall volumetric analysis.