Modification of PA66 fibres with in-situ polymerisation of 2- hydroxyethylmethacrylate

Poly(hydroxyethylmethacrylate) (pHEMA) was successfully introduced as an adhesion promotion layer on polyamide 66 (PA66) fibre surface by graft polymerisation using hydrogenperoxide as initiator. The grafted pHEMA layer strongly changes the fibre surface chemistry by introducing oxygen containing groups that thereby improve the fabric's wettability and strengthen the interface to potential subsequent coating layers or matrix material in case of fibre reinforced composites. The grafting reaction and formation of grafted pHEMA could be monitored and verified using different microscopic and spectroscopic analytical techniques, e.g. SEM, FTIR and NMR. Furthermore, the influence of parameters such as time, temperature and post plasma treatment of the grafting process on the yield of pHEMA was investigated and optimised using a d-optimal experimental design. For the optimisation of the process, the design suggested short treatment times at lower process temperatures and plasma post treatment for the desired fabric properties as an improved wettability and minimised change on bulk properties.