Study On The Modification Of The Biodegradable Resin PBS

As people's emphasis on sustainable development and environmental protection is growing,more and more attention has been paid to the biodegradable polymer materials because of their green,recyclable and biodegradable properties in recent years.It is an important way to reduce the "white pollution" and alleviate the oil crisis to achieve sustainable development by replacing the traditional petroleum-based polymer materials with biodegradable polymer materials.Among them,polybutylene succinate(PBS)has become a research hotspot in recent years due to its advantages of complete biodegradability,non-toxic and harmless,and better overall performance.However,due to the low crystallization rate and poor toughness of PBS,its further application is limited.In this study,plasticizing modification and blending modification were used to modify PBS for its lack of toughness without sacrificing its biodegradability.The contents and conclusions are as follows:(1)In this part,an environmentally bio-based plasticizer(SDV)was synthesized by isosorbide and n-valeric acid and used to modify PBS,and a series of PBS/SDV blends were prepared.Then the effects of the amount of plasticizer on the mechanical properties,glass transition temperature,crystallinity,rheological properties and processability of PBS blends were studied.The results are as follows: After adding SDV,the glass transition temperature of PBS was lowered.The glass transition temperature(Tg)of the blends decreased by 12.4°C when the amount of SDV was 20%;the addition of SDV reduced the crystallinity of PBS,when the amount of SDV was 20%,the crystallinity decreased by 10.67%,but the crystal form did not change.SDV reduced the processing torque,viscosity,storage modulus and loss modulus of PBS melt,and improved the processing performance;SDV reduced the tensile strength and increased the notched impact strength of the blends.When the SDV content was 9%,the tensile strength of blends was 25 MPa,which was 28.57% lower compared with pure PBS;and its notched impact strength was 101 J/m,which was 152.5% higher than pure PBS.(2)In the second part,a series of PBS-g-GMA/PBAT blends with higher toughness were prepared by melt blending of PBAT and grafted PBS with GMA.The mechanical properties,glass transition temperature,crystallinity and rheological properties of the blends with different PBS-g-GMA/PBAT ratios were studied in this part.The results are as follows: as the content of PBAT in the blends increased,the glass transition temperature of the blends decreased.When the content of PBAT was 50%,the glass transition temperature of the blends decreased 3.68°C compared with pure PBS.And the addition of PBAT decreased the crystallinity of the blends,when the content of PBAT was 50%,the crystallinity of the blends decreased from 48.40% to 29.51%.The viscosity,storage modulus and loss modulus of the blends were increased after adding PBAT,meanwhile the melt strength was increased.In terms of mechanical properties of the blends,the notched impact strength increased meanwhile the tensile strength decreased gradually when the content of PBAT in the blends increased.The tensile strength of the blends was 14 MPa and 60% lower compared with pure PBS when the content of PBAT in the blends was 50%,and the notched impact strength was 397 J/ m,which was increased by 892.5% than pure PBS.