热氧老化对马来酸酐接枝聚丙烯的结构与性能的影响

Effect of Thermal Oxygen Aging on the Structure and Properties of Maleic Anhydride Grafted Polypropylene

以自制的马来酸酐接枝聚丙烯(PP-g-MAH)为研究对象,研究了PP-g-MAH对玻璃纤维增强聚丙烯材料性能的影响以及热氧老化对PP-g-MAH分子结构和性能的影响。结果表明,自制的PP-g-MAH大幅度提高了30%玻纤增强聚丙烯材料的力学性能;随着热氧老化时间的延长,PP-g-MAH的MFR不断增加,对玻璃纤维增强聚丙烯材料的力学性能的提升作用不断降低;通过凝胶色谱仪(GPC)、红外光谱(IR)和马来酸酐(MAH)接枝率测定结果的分析,热氧老化过程没有对PP分子链接枝的马来酸酐产生明显的影响,而是引起了聚丙烯分子链的断裂,造成PP-g-MAH分子量下降,导致自身力学性能下降,使得PP与玻璃纤维之间的界面强度下降,使得PP-g-MAH对玻璃纤维增强聚丙烯材料的力学性能提升作用下降。

The effect of maleic anhydride grafted polypropylene(PP-g-MAH)on the properties of glass fiber reinforced polypropylene materials and the effect of thermal oxygen aging on the molecular structure and properties of PP-g-MAH were studied.The results show that the self-made PP-g-MAH significantly improves the mechanical properties of 30%glass fiber reinforced polypropylene material.With the prolongation of thermal oxygen aging time,the MFR of PP-g-MAH continues to increase,and the improvement effect on the mechanical properties of glass fiber reinforced polypropylene materials continues to decrease.According to the analysis of gel chromatograph(GPC),infrared spectrum(IR)and maleic anhydride(MAH)grafting rate measurement results,the thermal oxidative aging process does not have a significant impact on the maleic anhydride of the PP molecular link branch,but causes the fracture of the polypropylene molecular chain,resulting in the decrease of PP-g-MAH molecular weight,resulting in the decline of its own mechanical properties,and the decline of the interface strength between PP and glass fiber.The improvement effect of PP-g-MAH on the mechanical properties of glass fiber reinforced polypropylene materials is reduced.