不饱和聚酯树脂／大麻纤维复合材料的热氧老化

采用模压工艺制备不饱和聚酯(UP)树脂/大麻纤维复合材料,研究了105℃下热氧老化600h前后复合材料力学性能的变化;采用傅立叶变换红外光谱仪(FTIR)对老化前后复合材料的结构进行对比分析,并通过SEM技术观察复合材料的断面形貌.结果表明,偶联剂KH570处理对复合材料力学性能的总体改善效果最佳.老化600h后,偶联剂处理复合材料具有的最佳力学性能如拉伸强度、拉伸模量、弯曲强度、弯曲模量及冲击强度分别为19.06MPa、5.78GPa、52.988MPa、1.01GPa和3.881kJ/m2.红外分析显示,偶联剂处理得到的复合材料在老化前后的红外图形变化不明显,有些吸收峰甚至得到了加强.SEM结果表明,老化600h后,偶联剂处理的复合材料中纤维仍能较均匀地分散在树脂基体中,两者间的界面粘结良好.

EFFECT OF THERMO-OXIDATIVE AGING ON PROPERTIES OF HEMP FIBER/UNSATURATED POLYESTER RESIN COMPOSITES

The unsaturated polyester resin reinforced/hemp fiber composites were formed by compression mold-ing process, the thermo-oxidative aging test was carried out for 600 hours at 105℃. The mechanical properties of different composites before and after aging were studied, and the changes of the structures of different materials through the aging test were investigated by FTIR technology, the morphologies of the fractured surfaces of some com-posites were observed by SEM. The result shows, treating the hemp fiber with silane coupling agent KH570 has the best comprehensive positive effect. The tensile strength, tensile modulus, flexural strength, flexural modulus and impact strength of the KH570 treated composite are correspondingly 19.06MPa, 5.78GPa, 52.988MPa, 1.01GPa and 3.881 kJ/mM2 after aging for 600 hours, which indicate that the composite still has the best mechanical proper-ties. The FTIR spectrum of the KH570 treated composite is almost the same before and after the test, and some ab-sorbances are even strengthened. SEM pictures show that the fibers still dissipate in the matrix of the KH570 treated composite homogeneously after aging for 600 hours.