he hydrolytic degradation of poly-
β
-(hydroxybutyrate) PHB, poly-
β
-(hydroxybutyrate-co-
β
-valerate) (PHBV) and PHBV/cellulose triacetate blend was studiedunder different pH at 37 °C. PHBV showed a similar trend of degradation to PHB but at higher rates in alkaline medium. The presence of cellulose triacetate in the blend increased thewater uptake and permeability which favoured the hydrolytic degradation especially in lower pH medium. In the surface hydrolysis of PHB and its blends, the overall degradation rate wasincreased with higher pH values. The melting temperature, crystallinity and tensile propertieswere also determined. The blend, PHBV/CTAc had the lowest crystallinity values and PHBhad the highest. However, the blends were mechanically better in strength and toughness.