Synthesis, Characterization, and Enzymatic Degradation Studies on Novel Network Aliphatic Polyesters

Abstract

Network polyesters were prepared from1,1,1-trimethylolethane (Ye), 1,1,1-trimethylolpropane (Yp), 1,2,3,4-butanetetrol (Xe), and d-glucitol (Zs) with aliphatic dicarboxylic acids containing different numbers of methylene groups (HOOC(CH2)n-2COOH, n =4, 6−14, 16, and 20). Prepolymers prepared by melt polycondensation were cast from dimethylformamide solution and postpolymerized at 230 °C for 4 h to form a network. The resultant films were transparent, flexible, and insoluble in organic solvents. The network polyesters obtained were characterized by infrared absorption spectra, wide-angle X-ray diffraction analysis, density measurement, thermomechanical analysis, differential scanning calorimetry, and tensile test. The enzymatic degradation was estimated by the weight loss of the network polyester films in a buffer solution with lipase enzymes at 37 °C. The enzymatic degradation for Yen films was compared with that for the network polyester films of glycerol (Yg) or pentaerithritol (Xp) with various aliphat...