最大界面剪切应力的估算与芳纶复合材料界面粘结的表征

研究以估算的最大界面剪切应力，表征芳纶Ｋｅｖｌａｒ４９复合材料的界面粘结。依据Ｇｒｅｓｚｃｚｕｋ模型和单纤维拔出实验数据估算最大界面剪切应力，研究纤维表面处理和基体改性对界面粘结的影响。选用不同活性基团表面的芳纶Ｋｅｖｌａｒ４９和两种耐高温树脂基体组成强粘结界面体系的研究结果表明，实验数据与理论曲线拟合很好。

On Effect of Aramid Fiber Surface Treatment and Resin Modification on inter facial Bond of Composites

In China's search for high performance heat- resistant composites, one of many problems to be solved is how to obtain optimum interfacial properties. We now report on work done on a research project, which is one of several projects recently supported by NNSFC (National Natural Science Foundation of China).We deem that interfacial shearing strength is a key interfacial property. The maximum shearing stress according to Greszczuk's model7] is given by eq. (3). We perform the single fiber pull- out test. Substituting such test data into eq. (3), we can compute the interfacial shearing strength. We raise such strength by over 60% by treating surface of aramid fibers(Kevlar 49) with allyl or epoxy groups, which was proposed in the 1987 paper of Takayanagi et al8](the first author being a coauthor of Takayanagi's paper).Fins. 3 and 4 are for the matrix of toughened bismaleimide resin. Fig. 3 (untreated fibers) and Fig. 4 (fibers treated with allyl) show the variation of interfacial shearing stress with embedded fiber length.Fins. 5 and 6 are for the matrix of bismaleimide resin with improved adhesion. Fig. 5 (untreated fibers) and Fig. 6 (fibers treated with epoxy groups) show corresponding varistion of interfacial shearing stress with embedded fiber length.