Published online by Cambridge University Press: 01 February 2011
The degradation of PMMA-CNT thin film composites was examined, using electron beam radiation as a function of CNTs concentration. The findings show that the addition of CNT fillers can significantly reinforce composites against the irradiation induced degradation of PMMA, in which polymer free radicals are mainly responsible for the progress of the degradation. The results show that CNT networks are able to effectively disperse irradiated electrons through the matrix. The saturation of reinforcement effects was observed at a concentration of CNTs of approximately 0.5 wt%. This concentration was interpreted in terms of the critical concentration needed for percolation of the CNTs network, and this was further verified by sheet resistivity measurements. Free radical interactions with CNTs were also investigated by accelerated electron beam radiation and thermogravimetric analysis. CNTs were able to inhibit the free radical proliferation during a degradation process and to reduce the extent of degradation of the composites.