PHB, P(HB-CO-9-PERCENT HV) AND P(HB-CO-22 -PERCENT HV) MEMBRANES FOR MICROFILTRATION OR PERVAPORATION - FILTRATION PROPERTIES AND SURFACE-STATE

Microfiltration porous membranes (J(H2O) = 15,800 1/m(2) . atm . j, r( p) = 0,25 mu m) and pervaporation dense membranes for ethanol deshydra tation (J(total) = 0,008 kg/j . m(2), alpha = 12,6) were prepared from polyhydroxybutyrate, poly(hydroxybutyrate-co-hydroxyvalerate) with 9% and 22% valerate contents. Different surface structures characterized with contact angle, surface energy and scanning electronic microscopy were correlated with filtration properties. Membranes were prepared a fter immersion coagulation or total evaporation from different ternary system P-S-NS compositions.