Biodegradable aliphatic polyester .1. Synthesis and physical properties of copolyesterethylene

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, H-1-NMR, and C-13-NMR. The M(n) of the copolymer by GPC was varied out in the range of about 40000 similar to 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 similar to 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/cm(3). 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.