Abstract: A series of branched poly(butylene adipate) (BPBA) were synthesized by using adipic acid and 1,4-butanediol as raw materials and glycerol as a branching agent. BPBA was used as a plasticizer for poly(vinyl chloride) (PVC), and a comparative investigation on the plasticizing effect was performed between BPBA and other four classical plasticizers, including dioctyl phthalate (DOP), linear poly(butylene adipate) (LPBA), epoxy soybean oil (ESBO) and acetyl acetyl citrate (ATBC). The results indicated that the resultant BPBA achieved a minimum viscosity of 0.105 dL/g at the branching agent content of 0.5 % and the reaction time of 5 h. BPBA exhibited a better plasticizing effect for PVC than LPBA and ESBO, and the PVC plasticized with 0.5 wt % BPBA gained an improvement by 22.4 % and 14.6 % in elongation at break compared with LPBA and ESBO, respectively. Moreover, the low temperature toughness also increased by 15.7 % and 34.8 %. In addition, BPBA exhibited a better thermal stability and resistance to migration in comparison with DOP and ATBC.

Key words: poly(butylene adipate), poly(vinyl chloride), branching, plasticizer, migration