FKM/MWCNTs复合材料在稀氧介质中的耐老化性能

Mechanical properties and aging resistance of FKM/MWCNTs composites

以氟橡胶(FKM)为基体,多壁碳纳米管(MWCNTs)为补强剂,制备了FKM/MWCNTs复合材料。研究了MWCNTs含量对FKM复合材料的硫化特征曲线、力学性能、耐老化性能和微观结构等的影响。结果表明,随着MWCNTs的增加,材料的焦烧时间(t_(10))、正硫化时间(t_(90))、最高扭矩(M_(H))和交联密度相关的扭矩差(M_(H)-M_(L))逐渐增加;同时提升了材料的拉伸强度、定伸强度、硬度、撕裂强度和扯断永久变形,降低了扯断伸长率。在高温(177℃、204℃及232℃)稀氧环境下介质老化144 h后,FKM表现出较好的耐老化性。当MWCNTs含量较高时,FKM的耐老化能力并未表现出与MWCNTs含量的正向关系,仅适当的MWCNTs添加量,MWCNTs才能有助于提升FKM复合材料的力学性能和耐老化能力。

With fluororubber(FKM)as matrix and multi-walled carbon nanotubes(MWCNTs)as reinforcing agent,FKM/MWCNTs composites were prepared.The effects of MWCNTs content on the vulcanization characteristic curve,mechanical properties,aging resistance and microstructure of FKM/MWCNTs composites were studied.The results showed that with the increase of MWCNTs addition,the scorch time(t_(10)),positive vulcanization time(t_(90)),maximum torque(M_(H))and crosslink density-related torque difference(M_(H)-M_(L))of FKM/MWCNTs composites gradually increased,while the tensile strength,constant elongation,hardness,tear strength and tensile permanent deformation were improved,and the elongation at break was reduced.After being aged for 144 hours in a high temperature(177℃,204℃and 232℃)dilute oxygen environment medium,FKM/MWCNTs composites showed good aging resistance.When the content of MWCNTs was high,the aging resistance of FKM/MWCNTs composites did not show a positive relationship with the content of MWCNTs.The mechanical properties and again resistance of FKM/MWCNTs composites were improved,only with the proper amount of MWCNTs added.