软木纤维增强PP复合材料的研究

采用软木纤维作为增强材料提高聚丙烯性能。为了改善软木纤维和聚丙烯母体之间的相容性,用马来酸酐接枝聚丙烯(MAPP)对软木纤维进行接枝处理,用MAPP或用三元乙丙橡胶(EPDM)对软木纤维进行改性处理。结果表明,与未经处理木纤维的复合材料相比,三种处理方法都使复合材料的热性能、加工性能和力学性能有了较大的提高。用MAPP接枝和用MAPP表面处理木纤维的方法比用EPDM表面处理木纤维的方法在提高复合材料热性能、加工流动性和拉伸强度方面更为显著。用EPDM表面处理木纤维在改善复合材料的冲击强度、断裂伸长率上更明显。此外,木纤维在复合材料中的浓度对复合材料其它性能的影响,以及MAPP接枝木纤维和MAPP处理木纤维的不同实验结果也进行了评价。

Softwood Fibers as Reinforcing Materials for Polypropylene Based Composites

Softwood fibers were used to reinforce polypropylene (PP). To improve the compatibility between softwood fibers and the PP matrix, the fibers were either grafted with maleated polypropylene (MAPP), treated by adding MAPP, or mixed with ethylene/propylene/diene terpolymer (EPDM). The treatments resulted in improved processing as well as improvements in thermal and mechanical properties of the resultant composites compared with the composites filled with untreated softwood fibers. Moreover, MAPP grafting and MAPP treating displayed more obvious benefits than EPDM treating in terms of thermal properties, processing flowability and tensile strength improvements. EPDM treating also produced more significant benefits than either MAPP grafting or MAPP treating in terms of impact strength and tensile elongation improvements. These improvements were attributed to surface coating of the fibers when EPDM was used. In addition, the effect of the concentration of the softwood fibers on the properties of composites and the difference between MAPP grafting and MAPP treating were evaluated.