Thermolability, enzymatic degradation and aminolysis of solution-grown single crystals of novel poly(ethylene succinate-co-5mol% trimethylene succinate)s

Solution-grown single crystals of poly(ethylene succinate-co-trimethylene succinate)s (PETSA) were hydrolyzed by polyhydroxybutyrate (PHB) depolymerase from Ralstonia pickettii T1. Enzymatic degradation proceeded from the edges of the lamellar crystals, yielding serrated contours and small crystal fragments. On the other hand, single PETSA crystals were aminolyzed in 20 % aqueous methylamine solution to remove the folded chain regions, and enzymatically degraded using PHB depolymerase to remove poly(trimethylene succinate)—PTSA—components at the surfaces of single aminolyzed crystals. It was found that a small amount of PTSA component could be incorporated into the poly(ethylene succinate)—PESA—mother crystal lattice irrespective of the PTSA content.