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Novel biodegradable aliphatic polyesters,poly(butylene succinate-co-triethylene glycol succinate)(P(BS-co-TEGS))and poly(butylene succinate)(PBS),were synthesized through a two-step procedure of esterification and polycondensation with succinic acid and1,4-butanediol/triethylene glycol as raw materials as well as tetrabutyl titanate and diphenylphosphinic acid as the co-catalysts.The chemical structure and molecular weight of the copolymers were characterized by 1~H nuclear magnetic resonance(~1H NMR)and gel permeation chromatography(GPC),respectively.In addition,thermal properties,crystal structure and mechanical properties were also analyzed with various techniques.P(BS-co-TEGS)exhibited more excellent mechanical properties than PBS,especially in elongation at break.Meanwhile,the crystal structure and thermal stability of the P(BS-co-TEGS)have hardly changed.The crystallinity of P(BS-co-TEGS)was lower than that of PBS and decreased with the increase of mole ratio of triethylene glycol.With the increase of TEGS unit molar composition,the melting point(T_m),crystallization temperatures(T_c)and heat of fusion(ΔH_m)of P(BS-co-TEGS)decreased,while glass transition temperature(T_g)increased.
Novel biodegradable aliphatic polyesters, poly (butylene succinate-co-triethylene glycol succinate) (P (BS-co-TEGS)) and poly (butylene succinate) (PBS) were synthesized through a two-step procedure of esterification and polycondensation with succinic acid and 1,4-butanediol / triethylene glycol as raw materials as well as tetrabutyl titanate and diphenylphosphinic acid as the co-catalysts. The chemical structure and molecular weight of the copolymers were 1 ~ H nuclear magnetic resonance (~ 1H NMR) and gel permeation chromatography (GPC), respectively. In addition, thermal properties, crystal structure and mechanical properties were also analyzed with various techniques.P (BS-co-TEGS) exhibited more excellent mechanical properties than PBS, especially in elongation at break.Meanwhile , the crystal structure and thermal stability of the P (BS-co-TEGS) have hardly changed. crystallinity of P (BS-co-TEGS) was lower than that of PBS and decreased with the increase of mole ratio of triethylene glyco l.With the increase of TEGS unit molar composition, the melting point (T_m), the crystallization temperatures (T_c) and heat of fusion (ΔH_m) of P (BS-co-TEGS) decreased, while glass transition temperature (T_g) increased.