材料期刊网

利用超声作用制备纳米石墨微片（nano-Os），并采用混酸对其进行表面活化，最后通过熔融共混法制备nano-Gs／聚氯乙烯（PVC）复合材料。通过FTIR、SEM对nano-Gs的结构进行表征，并研究了nano-Gs对nano-Gs／PVC复合材料导电性能和力学性能的影响。FTIR分析表明：nano-Gs经混酸处理后表面活性官能团含量明显升高，并与PVC分子链发生一定程度的氢键作用；SEM图片显示：nano-Gs厚度为30-80nm，其微片宽度为4-20μm，在PVC树脂基体中呈无规状均匀分布；导电性能测试表明：随着nano-Gs含量升高，nano-Gs／PVC复合材料的体积电阻率呈非线性降低趋势，最低为10^[3]Ω·cm，nano-Gs的逾渗阈值为10％（质量分数）；力学性能测试表明，随着nano-Gs含量升高，nano-Gs／PVC复合材料的拉伸强度及缺口冲击强度均先升高后降低，nano-Gs质量分数为1％时，复合材料的拉伸强度及缺口冲击强度均达到最大值，相比纯PVC分别升高约14％和38％。

Graphite nanosheets （nano-Gs） were prepared via sonication and then activated with mixed acid, finally the nano-Gs/PVC composites were prepared by way of melt blending. The structure of nano-Gs was characterized by FTIR and SEM, and the impact of nano-Gs on the conductive and mechanical properties of nano-Gs/PVC composites was also studied. The FTIR spectra demonstrate that the surface-active functional groups of nano Gs increase significantly after mixed acid treatment, which form a certain degree of hydrogen bonding with PVC molecular chains. The SEM micrographs show that nano-Gs have a thickness ranging 30- 80 nm and a diameter ranging 4-20 ~m, and disperse randomly in PVC resin matrix. The electrical performance testing indicates that with the increase of the filled nano-Gs, the volume resistivity of the nano Gs/PVC composites decreases nonlinearly and reachs the lowest value of 10^[3]Ω cm when the mass fraction of nano-Gs reachs its percolation threshold （10%）. The mechanics performance testing shows that with the increase of the filled nano-Gs, both the tensile strength and notched impact strength of the composites increase first and then decrease, when the mass fraction of nano-Gs is 1%, the tensile strength and notched impact strength achieve the maximal value simultaneously and increase by 14 and 38% respectively compared with the pure PVC.