Biodegradation of Injection Molded Starch-Poly (3-hydroxybutyrate- co -3-hydroxyvalerate) Blends in a Natural Compost Environment

摘要: Injection molded specimens were prepared by blending poly (hydroxybutyrate-co-valerate) (PHBV) with cornstarch. Blended formulations incorporated 30% or 50% starch in the presence absence of poly-(ethylene oxide) (PEO), which enhances adherence granules to PHBV. These evaluated for their biodegradability natural compost measuring changes physical and chemical properties over a period 125 days. The degradation plastic material, as evidenced weight loss deterioration tensile properties, correlated amount present blends (neat PHBV < starch). Incorporation PEO into starch-PHBV had little no effect on rate loss. Starch degraded faster than it accelerated degradation. Also, did not retard After days exposure compost, neat lost 7% its (0.056% loss/day), while component blend 41% (0.328% loss/day). PHB PHV moieties within copolymer at similar rates, regardless starch, determined 1H-NMR spectroscopy. GPC analyses revealed that, number average molecular (Mn) all exposed samples decreased, there was significant difference this decrease between opposed blended starch. SEM showed homogeneously distributed embedded matrix, typical filler material. rapidly depleted during increasing surface area matrix.