Investigation On Modification Of Bio-based Polybutylene Succinate

Polybutanediol succinate(PBS)is a biopolymer material with good properties,which is widely used in packaging,medical and agricultural fields.However,PBS is limited in its application due to its brittleness,low toughness and slow crystallization rate.In this paper,PBS was modified by inorganic and organic methods respectively,and its structure and properties were characterized in a series of ways.The main research contents and conclusions are as follows:1.Nano silica was modified by ethylene triethoxysilane(VTES),and then blended with PBS to obtain PBS/SiO₂ nano composite.The effects of the addition of VTES on the grafting rate of modified nano SiO₂ and the effects of the addition of modified nano SiO₂ on the thermal stability,crystallization performance and mechanical properties of PBS/SiO₂nano composite were studied.The results were as follows:the graft rate of the maximum coupling agent was 0.99 wt%when 4 wt%VTES was added.The modified nano-silica composite still has good thermal stability.Nano silicon dioxide has heterogeneous nucleation effect to the PBS substrate,add 2 wt%of nano SiO₂ when the crystallization temperature increased 6.5°C,maximum crystallization rate,PBS crystal shape is not changed;The tensile strength and impact strength of PBS/SiO₂ nanocomposites were improved after the addition of modified SiO₂.When the addition amount of modified SiO₂ was 4 wt%,the tensile strength was 36.2 MPa,an increase of 11.4%compared with that of pure PBS.When the addition amount of modified SiO₂ was 8 wt%,the impact strength was 8.3 k J/m²,which was76.9%higher than that of pure PBS;2.A series of polybutylene succinate/isopentyl glycol esters(PBSM)were synthesized by melt copolymerization and then blended with PBS to obtain PBS/PBSM blends.The effects of isoprene(MBD)content on the thermal stability,crystallization and mechanical properties of PBS/PBSM blends were studied.The results were as follows:PBSM had little effect on the thermal stability of the blend system;After the addition of PBSM,the spherulite of the blend became smaller,the crystal shape did not change,and the crystallinity decreased.When the MBD content was 10 wt%,the crystallization rate of the system was the highest.The impact strength of PBS/PBSM blends was improved and the tensile properties were not significantly changed,When the MBD content was 15 wt%,When PBS/PBSM blends have higher impact strength,lower tensile strength and MBD content of 15 wt%,the maximum impact strength is 6.3 k J/m²,and the toughness increases by 32.7%compared with pure PBS.