Study On The Synthesis Technology Of The Derivatives Of Poly Succinic Acid Ester

Due to the"white pollution"caused by traditional non-degradable plastics and the shortage of petrochemical products as non-renewable resources,the research of biodegradable plastics has become an inevitable trend.Poly(butylene succinate)(PBS)is currently recognized as the biodegradable plastic with the best comprehensive properties.Compared with other biodegradable plastics,PBS has more excelent mechanical properties,heat resistance and processing performance.However,the poor impact resistance and the slow rate of biodegradation of PBS restrict its wide applications.In this paper,the impact resistance and the biodegradation rate of PBS was improved by copolymerizatio n modification and optimization of the reaction conditions,making it more suitable for industrial production.A series of derivatives of poly succinic acid ester were synthesized by melt polycondensation from succinic acid and aliphatic diols,including poly(butyle ne succinate)(PBS),poly(butylene succinate-co-diethylene glycol succinate)(P(BS-co-DEGS))and poly(butylene succinate-co-triethylene glycol succinate)(P(BS-co-TEGS)).The effects of catalyst,amount of catalyst,reaction temperature and copolymerization ratio on the reaction were studied with the intrinsic viscosity as the basis,thereby determining the optimum conditions of the polymerization.The structure and molecular weight of the products were characterized by nuclear magnetic resonance spectroscopy(~1H NMR)and gel permeation chromatography(GPC),respectively.The thermal,crystal ine and tensile properties of the products were characterized by differential scanning calorimetry(DSC),thermogravimetric analysis(TGA),wide-angle X-ray diffraction(WAXD)and mechanical testing,respectively.The results showed that the number average molecular weight of the synthesized products reached more than 50,000.The elongation at break of the synthesized copolyesters,such as P(BS-co-DEGS),was close to 800%,which was significantly higher than that of PBS.The crystallinity of P(BS-co-DEGS)was close to 30%,significantly lower than PBS.The synthes ized copolyesters all had good thermal stability and was able to meet the requirements of the use of biodegradable plastics.