Effect of organo clay concentration on the properties of radiation crosslinked natural rubber/ethylene vinyl acetate/clay nano composites

Effect of organo clay concentration on the properties of radiation crosslinked natural rubber (NR)/ethylene vinyl acetate (EVA)/clay nano composites was investigated. The NR/EVA blend-based nano composites with different concentration of either dodecyl ammonium montmorillonite (DDA-MMT) or dimethyl dihydrogenated tallow quarternary ammonium montmorillonite (C20A) were prepared by melt blending using a Haake internal mixer. The compounds were irradiated with electron beam (EB) at an optimum irradiation dose of 150 kGy. Changes in crosslinked density, tensile modulus, tensile strength and elongation at break of the nano composites were investigated. The gel content results reveal that the formation of radiation-induced crosslinking network does not change significantly with the increase of DDA-MMT content in the nano composite, however it reduce with the increase of C20A. XRD results reveal that the interlayer distance of the clay layers decrease slightly after irradiation. All mechanical properties increase after irradiation with exception of elongation at break. The decomposition temperature of the nano composites was increased with the increase of organo clay content up to 5 phr. (Author)