Study on Improving the Toughness and Heat Resistance of Polylactic Acid Insulation Materials by Blending Impact Modifier and Annealing Treatment

In this study, 10wt % of methyl methacrylate-butadiene-styrene (MBS) copolymer was introduced into PLA, and the heat resistance of the material was improved by annealing. The MBS/PLA mixture before and after annealing was comprehensively characterized by mechanical test, scanning electron microscope, thermal deformation temperature test, X-ray diffractometer, FTIR spectrometer and high voltage breakdown test. The mechanical test results show that MBS, as an effective toughening agent, can improve the notched impact strength of PLA materials from 17.34 kJ/m² to 74.34 kJ/m². The heat deformation temperature test shows that annealing treatment can improve the heat resistance of MBS/PLA mixture by 30.55 ℃. X-ray diffraction pattern shows that annealing treatment can improve the crystallization degree of MBS/PLA mixture. The power frequency breakdown voltage test shows that the addition of MBS only reduces the breakdown voltage of PLA by 12.34%, which means that the introduction of MBS does not significantly weaken the insulation performance of PLA, so it will not significantly affect its application potential in power equipment.