Synthesis Of Biodegradable Poly(Butylene Succinate)

Compared with other biodegradable polyester materials, poly (butylene succinate)(PBS) has a wide range of applications and good prospects for development because of its good mechanical properties, heat resistance, machinability and lower prices.In this paper, succinic acid (SA) and butanediol (BD) were used as raw materials. The synthesis process of PBS was studied systematically in glass tube reactor and2000ml stainless steel autoclave reactor respectively by melt polycondensation method. And how the products and reaction process were affected by influencing factors that included kinds and concentrations of catalysts, reaction temperature, reaction time and the ratio of raw materials were also sthdied. The structure and thermal properties of products were characterized by Fourier transform infrared spectrometer (FTIR), nuclear magnetic resonance(1H-NMR), differential scanning calorimetry (DSC), thermal gravimetric analysis (TG) and so on. The mechanical properties of product were characterized by stretching, bending and impact experiments.Kinds and concentrations of catalysts and reaction conditions for the synthesis of PBS were studied in glass tubes. Stannous chloride/p-toluenesulfonic acid catalyst system was selected due to its high catalytic efficiency. The influence of reaction conditions on molecular weight were also studied systematically. And on this basis process optimization research of scale-up experiment was conducted in the tank reactor zoom. The amount of stannous chloride and p-toluenesulfonic acid optimized were1%and1.5%(the molar ratio of succinic acid) respectively; The optimum mole ratio of butanediol and succinic acid was1.15; The best esterification reaction temperature was150℃, the polymerization temperature was205℃, and the reaction time was5h. PBS with a viscosity average molecular weight of1.1x105and a melt index of7.21g/10min was prepared under this condition, the melting point of which was114.2℃. When5%weight loss, the thermal decomposition temperature was about350℃. The tensile strength and bending strength of PBS synthesized were about40MPa and34MPa respectively, and the impact strength was up to5.0kJ/m2. The main performance indicators have reached the level of imported products. And this research has made a wealth of experimental data, which provides an important basis for further pilot-scale experiment.