碳纤维-Ni/尼龙66复合材料的制备与性能表征
Preparation and properties of carbon fiber-Ni/nylon 66 composites

为制备低电阻率的尼龙66基复合材料，以碳纤维和镍粉（Ni）填充尼龙66制备碳纤维-Ni/尼龙66高导电复合材料。研究填料表面改性和含量对碳纤维-Ni/尼龙66复合材料导电性能和力学性能的影响。结果表明：KH550改性碳纤维和Ni有助于降低碳纤维-Ni/尼龙66复合材料的电阻率。碳纤维-Ni/尼龙66复合材料的电阻率随着碳纤维和Ni含量的增加而减小，且碳纤维和Ni填充尼龙66的导电逾渗阈值均为20 wt%，此时制备的碳纤维-Ni/尼龙66复合材料的电阻率为455 Ω·cm，熔融温度为202.2℃。碳纤维-Ni/尼龙66复合材料的弯曲强度和拉伸强度随着碳纤维或Ni含量的增加而先增大后减小。当Ni含量为20 wt%时，碳纤维-Ni/尼龙66复合材料的弯曲强度和拉伸强度在碳纤维含量分别为20 wt%和10 wt%时达到最大值，分别为98 MPa和70 MPa；当碳纤维含量为20 wt%时，碳纤维-Ni/尼龙66复合材料的弯曲强度和拉伸强度则在Ni含量为30 wt%和20 wt%时达到最大值，分别为120 MPa和67 MPa。 In this study, in order to obtain nylon 66-based composites with low electrical resistivity, carbon fiber-Ni/nylon 66 composites were prepared by a plastic extruder with carbon fiber (CF) and nickel powder (Ni) as the paddings, nylon 66 as the raw resin. The relationships of the surficial modification and the fractions of CF and Ni between the electrical resistivity and mechanical properties of CF-Ni/nylon 66 composites were studied. The results show that the modification by KH550 and increasing of CF and Ni are of advantage to decrease the electric resistivity of CF-Ni/nylon 66 composites. And the electrical percolation thresholds of CF and Ni both are 20 wt%. The electric resistivity of CF-Ni/nylon 66 composite is 455 Ω·cm at the percolation thresholds, and its melting point is 202.2℃. The flexural strength and tensile strength of CF-Ni/nylon 66 composites increase firstly and decrease lately with the increasing of CF and Ni. When the fraction of Ni is 20 wt%, the flexural strength of CF-Ni/nylon 66 composite reaches to the maximum 98 MPa as the fraction of CF is 20 wt%, and the tensile strength reaches to the maximum 70 MPa as the fraction is 10 wt%. When the fraction of CF is 20 wt%, the flexural strength of CF-Ni/nylon 66 composite reaches to the maximum 120 MPa as the fraction of Ni is 30 wt%, and the tensile strength reaches to the maximum 67 MPa as the fraction is 20 wt%. 深圳市知识创新计划（JCYJ20130402161506238）