通过甲苯-2，4-二异氰酸酯（TDI）和十八烷醇（S）对纳米二氧化硅（SiO₂）进行表面功能化制得改性SiO₂（SiO₂-TDIS）。将含有SiO₂-TDIS的油料加入己内酰胺单体，通过阴离子开环聚合制得含SiO₂-TDIS/油铸型（OMC）尼龙复合材料，以提高复合材料的综合性能。通过傅里叶红外（FT-IR）、热重分析（TGA）、扫描电镜（SEM）和万能试验机等手段对复合材料的结构与性能进行表征。结果表明，SiO₂-TDIS的表面接枝率为17.3%；SiO₂-TDIS/OMC尼龙材料的热稳定性增强，晶型以α型为主，SiO₂-TDIS在油滴中的稳定性增强；当质量分数为0.125%的SiO₂-TDIS加入OMC复合材料时，拉伸强度、缺口冲击强度和弯曲强度分别提高17.5%、57.7%和32.4%。SiO₂-TDIS的加入使OMC尼龙拥有较好的力学性能和摩擦性能。

SiO₂-TDIS is prepared through the surface functionalization of nano-SiO₂ by toluene-2, 4-diisocyanate (TDI) and stearyl alcohol (S).SiO₂-TDIS/oily monomer cast (OMC) nylon composites are gained through in situ anionic ring-opening polymerization by adding SiO₂-TDIS-containing oil products into caprolactam monomer, which is aiming at improving the comprehensive properties of the composites.The thermal behavior, crystal behavior, mechanical properties and microstructure of SiO₂-TDIS/OMC nylon composite are studied by means of FTIR, TGA, SEM, XRD and universal material testing system.The results show that the surface grafting rate of nano-SiO₂ reaches 17.3 wt%, the thermal stability of SiO₂-TDIS/OMC nylon material is enhanced, the crystalline form is dominated by α form and the stability of SiO₂-TDIS in oil droplets rises.When the addition amount of SiO₂-TDIS is 0.125 wt%, the tensile strength, notched impact strength and flexural strength of the composites increases by 17.5%, 57.7% and 32.4%, respectively.The addition of SiO₂-TDIS makes OMC nylon have better mechanical properties and friction properties.

王钦(1992-),男,硕士研究生,主要研究方向为有机功能材料,3135739494@qq.com。