微/纳米无机颗粒对聚氨酯-环氧树脂基复合材料性能的影响

通过机械搅拌混合法制备了微/纳米无机颗粒改性的聚氨酯-环氧树脂复合材料, 研究了颗粒组成和含量对复合材料力学和热稳定性的影响，进而探讨了所得复合材料的强韧化机理.结果表明: 相比微米颗粒，纳米颗粒的加入能显著提高复合材料的层间剪切强度和拉伸强度，降低层间剪切模量，同时改变材料的断裂方式.当纳米SiC颗粒的添加量(质量分数)为2%时，所得复合材料的层间剪切强度和拉伸强度分别为44.7 MPa和56.56 MPa，相比添加前提高约88%和74%，所得复合材料不同失重率下对应的温度较添加前提高了4~8 ℃.纳米颗粒弥散强化和钝化银纹扩展是复合材料主要的强韧化机理.
The mechanical blending method was used to prepare the micro/nano inorganic particle modified PU-EP composites. The influence of the composition and the amount of the particles on the properties of the PU-EP composites were studied, and the toughness mechanism of the obtained composites was also discussed. The results show that the addition of nanoparticles can noticeably improve the interlaminar shear strength and the tensile strength of the PU-EP composites, while reducing the elastic modulus and changing its fracture behaviors. When the content of the nano-SiC particles equaled 2%, the interlaminar shear strength and tensile strength of the composites reached 4.47 MPa and 56.56 MPa, an improvement of about 88% and 74% compared with that of un-modified composites. Also, the temperature corresponding to different weight-losses of the nano-SiC particle modified composites was improved by about 4~8 ℃. The nanoparticles dispersed and strengthened the blunt of the silver strip, which played an important role in the course of the toughness mechanism of the composites.