Radiation processed ethylene vinyl acetate-multiple walled carbon nanotube nano-composites: Effect of MWNT addition on the gel content and crosslinking density

Different compositions of ethylene vinyl acetate (EVA)/multiple walled carbon nanotube (MWNT) nano-composites were prepared by melt mixing and subjected to different doses of gamma radiation. The efficiency of radiation vulcanization was analyzed by sol-gel analysis, Charlesby-Pinner parameter estimation and crosslinking density measurements. Gamma radiation induced crosslinking was found to increase with MWNT fraction in EVA-MWNT nanocomposites (p(0)/q(0) in the range: 1.15-0.98). These results ruled out the possibility of a significant neutralization of single ionization spurs by MWNT addition. The incorporation of MWNT also resulted in increased hardness and higher density of the nano-composite matrix. The efficiency of multifunctional acrylates as crosslinking aid in the radiation-induced vulcanization of EVA-MWNT nano-composites was also investigated. The results established lower efficiency of methacrylates than of acrylates in the radiation vulcanization process.