Abstract: A new method was explored to synthesize nylon 6 on the surface of carbon fiber by fiber activating and in-situ impregnating polymerization in order to equip with carbon fiber/nylon 6 composite on line production line on the carbon fiber production line. Firstly, the surface of carbon fiber was coated with a layer of TDI (2,4-toluene diisocyanate) which was used as activator to make the fiber activate. Then the activated fiber was passed through the monomer anion melt which was obtained from the system of caprolactam and an initiator sodium hydroxide by previously removing water. Finally, a layer of nylon 6 is formed on the surface of the fiber through diffusion and polymerization of monomer anion. The results showed that nylon 6 could be successfully formed on the surface of carbon fiber through fiber activating and in-situ impregnating polymerization process. However, the polymerization temperature has great influence on the conversion rate, melting crystallization behavior and molecular weight of nylon 6. And the excess activator also has an adverse effect on the conversion rate of nylon 6. If the ratio of activator could be improved, the conversion rate of polymer will be improved. Finally, the functional group distribution and microstructure of the material were detected by infrared spectroscopy and scanning electron microscopy (SEM).

Key words: in-situ polymerization, carbon fiber, nylon 6, conversion, melting and crystallization behavior