Poly(butyleneadipate-co-terephthalate)(PBAT) copolyesters were synthesized from adipic acid(AA)

p-phthalic acid(PTA) and 1

4-butanediol(BDO) with tetrabutyl titanate as catalyst through a two-step process of esterification and polycondesation.The effects of molar ratio of AA to PTA on the structures

thermal and elastic properties of copolyesters were studied.FTIR and NMR test results showed that PBAT copolyesters were successfully synthesized.GPC test showed the molecular weight(Mw) of copolyesters were between 41000-142000

which was consistent with the result of the intrinsic viscosity.DSC results showed that Tm and Tc were gradually reduced with the increase of adipic acid.WXRD test results indicated that with the increase of adipic acid

the crystal structure copolyesters gradually changed from PBA into PBT.DMA results showed that the Tg of copolyesters trended to decrease with the increase of adipic acid.From TGA curves

the initial decomposition temperature of PBAT copolyesters shifted to the high temperature zone

while the thermal stability of the copolyesters closed at high temperature.It was found from the tensile test that the AA/PTA ratio significantly affected the mechanical properties of copolyesters.PBAT7:3 was of the maximum elongation at break

and PBAT3:7 was of strong and tough tensile properties.