Studies of biodegradation of binary blends of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBHV) with poly(2-hydroxyethylmetacrilate) (PHEMA)

Biodegradation studies of binary blends of bacterial poly(hydroxybuyrate-co-hydroxyvalerate) (PHB-21%HV) with synthetic poly(2-hydroxyethylmetacrylate) (PHEMA) prepared by casting were performed. The compositions were explored in a range of 20-50% PHEMA on PHBHV. ASTM G21-90 including measurements of CO2 were used to determine biodegradability. The time required for biodegradation increased as PHEMA content in the blend increased. Although all blends were biodegradable, as determined by ASTM G21-90 method, the CO2 measurements could be indicative that the degradation of PHEMA, if it exists, is limited. Degradation of blends attained 90% (mass loss) in a period from 7 to 15 days, though after 30 days no degradation was detectable when PHEMA was tested as a single component. Penicillium funiculosum showed the highest degradation activity among five fungal species tested for biodegradation. Microscopic studies show that biodegradation of blends started at their surface. (C) 2003 Elsevier Ltd. All rights reserved.