The transesterification of poly(β-hydroxybutyrate) (PHB) and poly(ε-caprolactone) (PCL) was carried out by using stannous octoate as catalyzer in liquid phase．The effects of reaction conditions on the transesterification

including reaction temperature

reaction time and catalyzer content

were investigated．The sequence distribution

crystallization behavior and thermal stability of PHB-co-PCL copolyesters were studied by 13C-NMR

FTIR

DSC

WAXD and TGA．The results showed that the transesterification of PHB with PCL was confirmed to produce a block copolymer

and enhancing reaction temperature and increasing reaction time were advantageous to the transesterification. With the increase in PCL content in the block copolymer

the crystallization behavior of PHB-co-PCL copolyesters changed evidently．On the other hand

Lhe introduction of PCL segment into PHB chains did not change its crystalline structure；moreover

thermal stability of PHB-co-PCL copolyesters was a little improved in air

comparing with that of pure PHB．