Preparation of high performance fluoroelastomers by modifying carbon fiber with PEI and fluorinated coupling agent

A novel functionalized carbon fiber (CF) grafted with polyelectrolyte polyethyleneimine (PEI) and trimethoxy(1H,1H,2H,2H-heptadecafluorodecyl)silane (F17) was constructed by combining chemical grafting with oxidation method. The desized CF was first oxidized in concentrated acid and then grafted with PEI and F17. The effect of CF modification on the mechanical, thermal and electrical properties of fluoroelastomers (FKM) were systematically investigated. The results showed that the PEI and F17 grafted CF shows the highest mechanical properties’ enhancement function. Compared with blank FKM, the tensile strength, Young's modulus, modulus at 100 % strain and hardness achieved a 173 %, 117 %, 310 % and 30 % increment, respectively. The compression set sharply reduced to 20.61 % and exhibiting excellent anti-compression properties. In addition, the thermal and electrical properties were also improved. Such a high-performance functionalized CF exhibits excellent mechanical, thermal and electrical properties enhancement function and own great potential in industry.