Biodegradability and mechanical properties of poly-(beta-hydroxybutyrate-co-beta-hydroxyvalerate)-starch blends.
Wheat starch granules and poly-(beta-hydroxybutyrate-co-beta-hydroxyvalerate) [P(HB-co-HV), (19.1 mol% HV)] were blended at 160 degrees C. Increasing the starch content from 0 to 50% (wt/wt) decreased the tensile strength of P(HB-co-HV) from 18 MPa to 8 MPa and diminished flexibility as Young's modulus increased from 1,525 MPa to 2,498 MPa, but overall mechanical properties of the polymer remained in a useful range. A mixed microbial culture required more than 20 days to degrade 150-microns-thick samples of 100% P(HB-co-HV), whereas samples containing 50% (wt/wt) starch disappeared in fewer than 8 days. Starch granules degraded before P(HB-co-HV) did. Aerobic degradation proceeded more rapidly than anaerobic degradation.
Ramsay
B A
BA
Département de Génie Chimique, Ecole Polytechnique de Montréal, Québec, Canada.
Langlade
V
V
Carreau
P J
PJ
Ramsay
J A
JA
D000332:Aerobiosis; D000693:Anaerobiosis; D001673:Biodegradation, Environmental; D008855:Microscopy, Electron, Scanning; D011091:Polyesters / Q000737:chemistry / Q000378:metabolism*; D013213:Starch / Q000737:chemistry / Q000378:metabolism*; D000094122:Polyhydroxybutyrates
D011091:Polyesters; D013213:Starch; C052620:poly(3-hydroxybutyrate)-co-(3-hydroxyvalerate); D000094122:Polyhydroxybutyrates