改性剂对氧化石墨烯/铸型尼龙复合材料力学性能的影响

Effect of Modifiers on Mechanical Properties of Graphene Oxide/MC Nylon Composites

采用改进的Humeers法制备氧化石墨烯(GO),然后使用环氧丙基三甲基氯化铵(GTMAC)、十六烷基三甲基溴化铵(CTAB)、马来酸酐接枝高密度聚乙烯(HDPE-g-MAH)和马来酸酐接枝超高分子量聚乙烯(UHMWPE-g-MAH)四种不同柔性链的改性剂分别改性GO.并经傅里叶红外光谱(FTIR)、X射线衍射(XRD)及扫描电子显微镜(SEM)等对改性GO及铸型(MC)尼龙复合材料进行测试和表征,结果表明:CTAB改性GO层间距最大,在尼龙基体中分散最好。力学强度测试结果表明:改性GO的分散性对复合材料的性能影响较大,使用CTAB改性GO制得的MC尼龙复合材料性能最佳,当GO-g-CTAB加入量为己内酰胺用量的0.05%时,与未改性GO/MC尼龙复合材料相比,其弯曲强度提高了9.3%,冲击强度提高了60%,拉伸强度和压缩强度也分别提高了2.0%和15.8%。改性剂链的柔性对铸型尼龙综合力学性能也有重要的影响,HDPE和UHMWPE改性GO的添加显著提高了复合材料的冲击性能,但材料的拉伸强度略有下降。

Graphene oxide(GO) was synthesized by the modified Humeers method, and then modified by four different modifiers glycidyl trimethyl ammonium chloride(GTMAC), hexamethylethylammonium bromide (CTAB), maleic anhydride grafted HDPE(HDPE-g-MAH) and maleic anhydride grafted UHMWPE (UHMWPE-g-MAH), respectively. The structure and properties of the modified GO and composites were studied by fourier transform infrared(FTIR), X-ray diff raction(XRD) and scanning electron microscope(SEM). The results show that: CTAB modifi ed graphene oxide has the largest spacing and the best dispersion in nylon matrix. The results of mechanical strength test show that the dispersion of modified GO has a great influence on the properties of the composites. The properties of MC nylon composites modified by CTAB are the best. When the content of GOg-CTAB is 0.05% of caprolactam, the bending strength of the composites is increased by 9.3% and the impact strength is improved by 60%. The tensile strength and compressive strength is increased by 2% and 15.8% respectively. The flexibility of modifier chain also has an important effect on the comprehensive mechanical properties of cast nylon. HDPE and UHMWPE modified GO significantly improves the impact properties of the composites, but the tensile strength decreases slightly.