Biodegradable aliphatic copolyester, copolyesterethylene (CPEE), was synthesized by polycondensation of octadecane dicarboxylic acid with caprolactone diol and the sequential chain extension reaction with sebacoyl dichloride. The structure of the copolymer was identified by using FT-IR, ¹H-NMR, and ¹³C-NMR. The M_n of the copolymer by GPC was varied out in the range of about 40000∼60000 and the M_n of the copolymer formed by sequential chain extension reaction was increased about 20000. The copolymers possessed wide distribution with M_w/M_n values of 2.25∼2.61. The copolymer was very soluble in toluene, chloroform, THF, and dioxane, but insoluble in methanol, ethanol, and DMF. The density of CPEE was 0.60 g/㎤. The copolymers obtained by polycondensation and formed by sequential chain extension reaction exhibited similar values of melting point, tensile strength, elongation, and Izod impact strength.

생분해성 aliphatic copolyester인 copolyesterethylene (CPEE)을 octadecane dicarboxylic acid와 polycaprolactone diol과의 축중합 반응 및 sebacoyl dichloride에 의한 chain extension 반응을 통해 합성하고 공중합체의 구조를 FT-IR, ¹H-NMR 및 ¹³C-NMR을 사용하여 확인하였다. GPC에 의한 분자량 측정 결과 M_n값이 40000∼60000을 나타내었고 chain extension반웅에 의하여 약 20000 가량의 분자량 증가를 보였다. 분자량 분포값은 2.25∼2.61로 넓게 나타났다. 공중합체의 용해도 측정결과 toluene, chloroform, THF, dioxane에는 잘 녹았으나 methanol, ethanol, DMF 등에는 녹지 않았으며 밀도는 0.60g/㎤인 것으로 나타났다. DSC에 의한 녹는점, 만능시험기에 의한 인장강도와 신장율 및 Izod 충격강도는 축중합 및 chain extension에 의한 공중합체의 경우 비슷하게 나타났다

Keywords: biodegradable plymer; CPEF; chain extension reaction