The influence of oxygen containing functional groups on carbon fibers for mechanical properties and recyclability of CFRTPs made with in-situ polymerizable polyamide 6

The influence of the oxygen containing functional groups on carbon fibers for mechanical properties and recyclability of carbon fiber reinforced thermos-plastics (CFRTPs) made with in-situ polymelizable polyamide 6 (PA6) have been discussed. Interfacial adhesion between CFs with functional groups and PA6 became higher compared with that of because of the interaction such as hydrogen bond, covalent bond. Furthermore, it was revealed that these effects apparently improved the mechanical properties of the CFRTPs. On the other hand, the interaction between the functional groups and PA6 affected the recyclability of the CFRTPs. Although PA6 as the matrix polymer of the CFRTP could be pyrolyzed even under N2 gas and recycle CFs with very little char could be obtained at 600 °C, it was found that the tensile strength decreased after pyrolytic process by about 10% only when the CFs with the functional groups were used for reinforcement fibers.