Structure and properties of epoxidized nature rubber/organoclay nanocomposites

In recent years rubber/layered silicate nanocomposites have attracted great interest. Epoxidized natural rubber (ENR) combines the properties of natural rubber and polar rubber. Up to now, only few studies were devoted to ENR-based nanocomposites prepared by mixing intercalation method. In this paper, Organomodified clays of 10A, 15A and 20A were compounded with ENR (50% epoxidation), respectively. The nanometer scales of organoclays in rubber matrix were determined by X-ray diffraction testing, the exfoliated/intercalated structures of organoclay 15A in ENR were confirmed by transmission elector microscopy. The increases in tensile moduli and strengths of ENR/15A and ENR/20A nanocomposites vulcanizaters were caused by the better interactions between rubber macromolecule chains and organoclay layers. The curing characteristic and viscoelastic properties of uncured composites were determined by RPA2000. DMA test showed that the Tgs nanocomposites shifted a little to that of ENR vulcanizates. Nanocomposites of ENR/10A, ENR/15A and ENR/20A were obtained by mixing intercalation method. The addition of nanoclay 15A and 20A improved the mechanical properties of ENR, while the properties of ENR/10A was enhanced indistinctively.