聚丙烯/热致液晶聚合物/玻璃纤维混杂复合材料 Ⅱ: 混杂复合材料的静态及动态力学性能
PP/TLCP/GLASS FIBER HYBRID COMPOSITES Ⅱ : TENSILE AND DYNAMIC MECHANICAL PROPERTIES OF HYBRID COMPOSITES
-
摘要: 对具有良好液晶聚合物微纤结构的聚丙烯/热致液晶聚合物/玻璃纤维 (PP/TLCP/GF) 混杂复合材料,使用静态拉伸和动态力学分析 (DMA) 的方法研究了材料的力学性能。拉伸实验结果表明,混杂复合材料的拉伸强度和模量随着PP和TLCP挤出后的牵伸速率增大而上升,并且含有增容剂PP-g-MAH的体系,力学性能更优异。DMA测试结果表明,混杂复合材料的动态模量E'随着体系中玻纤的含量增加而增大;当体系中加入增容剂后,复合材料的刚性得到进一步提高。但无论是否使用了增容剂PP-g-MAH,当体系中玻纤含量高于20%后,模量随玻纤含量增大的趋势变缓。当体系中增强相的含量增加,以及加入增容剂使增强相与基体的界面粘结得到改善后,PP基体的损耗因子 (tanδ) 峰值都有一定的减小。Abstract: The tensile test and dynamic mechanical analysis (DMA) were conducted to investigate the mechanical properties of polypropylene/thermotropic liquid crystalline polymer/glass fiber (PP/TLCP/GF) hybrid composites with a good TLCP fibrils structure.The tensile test results show that the tensile strengths and moduli of hybrid composites increase with increasing drawing ratio after the extrusion of PP and TLCP.The hybrid composites compatibilized with PP-g-MAH have more excellent mechanical properties than the systems without the compatibilizer.The DMA results show that the dynamic storage moduli of hybrid composites increase with the increase of glass fiber content.The storage moduli, e.g.the rigidity of hybrid composites, increase further after the introduction of PP-g-MAH as the compatibilizer.Whether using PP-g-MAH as the compatibilizer or not, the increase of the storage moduli slows down after the glass fiber content reached 20% (mass fraction).The peak value of tanδ of the matrix decreases with increasing glass fiber content.The addition of PP-g-MAH as the compatibilizer also decreases this value after the modification of the interfacial adhesion between the matrix and reinforcing phase.