Crystallization Behavior And Properity Of Poly(butylene Succinate-co-butylene Diglycolate)and Poly(Butylene Succinate-co-butylene Thiodiglycolate)

The research and development of degradable material are essential to alleviate environment problem.Poly(butylene succi nate-co-butyl ene diglycolate)(PBSBDG)and Poly(butylene succinate-co-butylene thiodiglycolate)(PBSBTDG)were prepared through melt polycondensation method,the copolymers were studied by kinds of ways.The crystalline structure of PBSBDG was unchanged.The BDG unit suppress the process of nonisothermal and isothermal crystallization.With the content of BDG increasing,PBSBDG present a lower crystallization(Tcc)and melting temperature(Tm)accordingy,the equilibrium melting point(Tm0)values which were fitted by equation also decrease.In spite of the different BDG content and crystallization temperature(Tc),PBSBDG crystallized with the same mechanism.All the PBSBDG crystallized much more slowly with the increasing Tc.When the PBSBDG have 17 mol%and 26 mol%BDG,the banded spherulite morphology was presented.From the study of hydrolytic degradation behavior,the weight loss of PBSBDG is faster compared with PBS.Especially PBSBDG with 26 mol%BDG,whose weight loss rate is about 10 times rate of PBS.As the proportion of BDG in PBSBDG chains increasing,the greater degradation rate was determined.The crystal structure of PBSBTDG was almost consistent with that of PBS.PBSBTDG exhibit lower glass transition temperature(Tg)owning to the flexible BTDG segments in the PBSBTDG chains promoting the motility of molecular.The results of nonisothermal and isothermal crystallization of PBSBTDG have the similar trends with PBSBDG The banded spherulites were presented when PBSBTDG contained 15 mol%and 25 mol%BTDGThe tensile strength of PBSBTDG was relatively high and they were flexible,based on these properties,PBSBTDG can be applied as ductile polyester with wonderful mechanical performance.PBSBTDG degraded faster than PBS.As the content of BTDG in the PBSBTDG growing,the degradation rate of PBSBTDG increased.