Mechanical properties and enzymatic degradation of poly([R]-3-hydroxybutyrate-co-[R]-3-hydroxyhexanoate) uniaxially cold-drawn films

摘要: Uniaxially oriented films of poly([R]-3-hydroxybutyrate-co-[R]-3-hydroxyhexanoate) (P(3HB-co-3HH)) with 5 and 12 mol% 3HH comonomer were prepared by cold-drawing from an amorphous preform at temperatures near to the respective glass transition temperatures. Melt-quenched in a rubber state could be stretched reproducibly draw ratio 500%. Subsequent annealing under tension led improvement tensile strength Young's modulus. Two step drawing P(3HB-co-5%-3HH) resulted further mechanical properties. The X-ray fiber diagrams showed increasing orientation crystallinity ratio. properties remained unchanged after storing for several months room temperature, suggesting that high suppress secondary crystallization. Cold-drawn P(3HB-co-3HH) enzymatically degraded extracellular PHB depolymerase purified Ralstonia pickettii T1. enzymatic degradation was investigated means weight-loss profiles scanning electron microscopy.