Abstract: Blends of poly(hydroxhutyrate-co-hydroxyvalerate) /poly(hutylene succinate)(PHBV/PBS)were prepared by means of melting mixing added with triethyl citrate(TEL) and polyethylene glycol(PEG)as plasticizers respectively. The melting rate, thermal, crystalline, mechanical properties and phase morphology structure of the blends were characterized by means of MFI, DSC, XR1)，SEM and tensile tester. The results showed that the performance of the blends changed significantly with the increase of the content of plasticizers. When the content of plasticizers (PEG and TEL) was 10 phr, the melt flow rate of blends was 3 times and 1. 8 times more than pure PHBV/PBS blend respectively. The elongation at break was the maximum wherein the contents of PEG and TEL were 2. 5 phr and 10 phr.The crystalline temperature(Tc)and melting temperature(Tm) were slightly decreased when the amount of two plasticizers increased. SEM micrographs indicated that the joining of both plasticizers promoted interface combination between two phases.

Key words: poly(hydroxhutyrate-co-hydroxyvalerate);poly(butylene succinate);plasticizer, triethyl citrate, polyethylene glycol