New polyesters wore synthesized using Krebs cycle acids and characterized. Poly(1,4-butanediol dilactate succinate) and poly(1,4-butanediol dilactate 2-acetoxy succinate) were prepared by the poltcondensation of 1,4-butanediol dilactate with succinic anhydride and 2-acetoxy succinic acid. And poly(1,4-butanediol succinate) was synthesized from 1.4-butanediol and succinic anhydride. 1,4-Butanediol dilactate was synthesized from lactic acid in the presence of 1,4-butanediol as a difunctional monomer. 2-Acetoxy succinic acid was synthesized from L-malic acid by protecting hydroxyl group using acetic anhydride. The monomers and polymers were identified by ¹H-NMR spectrometer and FR-IR spectrophotometer. The molecular weight and molecular weight distributions of synthetic polymers were measured by gel permeation chromatography. The glass transition temperatures(T_g), melting temperature(T_m), and thermal decomposition temperatures of the polymers were measured by differential scanning calorimetry and thermogravimetry, respectively. The recrystallization and cold crystallization of the polymers were investigated in nonisothermal condition.

Krebs cyc]e acid 유도체를 이용하여 새로운 polyesters를 합성하였다. 1,4-butanediol dilactate와 succinic anhydride 및 2-acetoxy succinic acid를 사용하여 poly(1,4-butanediol dilactate succinate)와 poly(1.4-butanediol dilactate 2-acetoxy succinate)를 합성하였으며, 1,4-butanediol과 succinic anhydride를 이용하여 poly(1.4-butanediol succinate)를 합성하였다. 이 작용기를 갖는 1,4-butanediol dilactate는 tactic acid와 1,4-butanediol을 이용하여 합성하였으며 2-acetoxy sucrinic acid는 acetic anhydride를 이용하여 L-malic acid의 히드륵시기를 .보호하여 합성하였다. 단량체와 중합체들은 적외선흡수분광기와 핵자기공명분광기를 이용하여 확인하였으며 분자량 및 분자량분포는 GPC법으로 측정하였다. 시차주사열량계와 열무게측정기를 이용하여 중합체의 유리전이온도, 용융온도 및 열분해온도를 측정하였다. 또한 중합체의 재결정화현상과 냉결정화현상을 비등온과정에서 조사하였다.

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