Design,Preparation And Properties Of PBS/Starch Composites

The increasing dependence on plastic products,the difficulty of natural decomposition of traditional petroleum-based materials and the bad habits of people in discarding waste have made"white pollution"an increasing threat to human beings.Polybutylene succinate(PBS)is an organic polymer with excellent performance and has been highly anticipated to replace traditional petroleum-based plastics.However,the high manufacturing cost and certain deficiencies in performance have limited the process.In this paper,an attempt was made to modify PBS resins using low-cost thermoplastic starch(TPS)without sacrificing the biodegradable properties of PBS,as follows.(1)In the first part of the work,an environmentally friendly compound anhydrous xylitol tripelargonate(AXP)was prepared for plasticizing starch.The synthesized products were verified by nuclear magnetic resonance hydrogen spectroscopy as well as Fourier infrared spectroscopy,and then the experimental conditions were optimized using a one-factor approach.The optimum reaction conditions were determined as follows:the molar ratio of alcohol to acid molar ratio was 1:3.5;the catalyst was p-toluenesulfonic acid(PTSA)with a mass fraction of 1%;the reaction temperature was 150°C;the reaction time was 4 h;toluene was used as a water-carrying agent to promote the reaction go forward.At the same time,PBS/TPS composites were prepared,and the effect of TPS addition on the properties of the composites was analyzed and discussed.The study found that the impact strength of the composite material increased compared with that of pure PBS.When the addition amount was 10%,it increased by 19%.The tensile modulus first decreased and then increased.When the addition amount was 30%,it was similar to pure PBS.The ratio increased by 25%;the crystallinity decreased slightly,but the crystal form did not change;the glass transition temperature gradually decreased;the addition of TPS improved the processability of the system.(2)In the second part of the work,in order to improve the compatibility and toughness of the composites,PBS-g-GMA/TPS/PBAT composites were prepared by modifying them with glycidyl methacrylate(GMA)and polybutylene terephthalate(PBAT)respectively.The addition of PBAT significantly improves the toughness of the composite material.When the addition amount is 35%,the impact strength is increased by 172.5%compared with pure PBS;the storage modulus,loss modulus and complex viscosity of the composite material are improved,the processing performance of the system is obviously improved;the crystallization temperature T_c does not change much,indicating that the addition of PBAT has little effect on the crystallization ability of the system,but it will reduce the crystallinity.The microscopic morphology observation found that in the PBS-g-GMA/TPS composite,the interface between the TPS microspheres and the PBS matrix became blurred,indicating that the compatibility between the two phases was improved;in the process of increasing PBAT,the impact section gradually became rough,indicating that the material transitions towards ductile fracture,further confirming its ductility gain effect.