Effect of the Compatibilizer Upon the Properties of Styrene-butadiene Rubber Organoclay Nanocomposites

Nanocomposite vulcunizates based on styrene-butadiene rubber (SBR), organoclay and a conventional sulfur curing system were prepared by melt blending process in an internal mixer. In order to study the effects of the type of interfacial compatibilizer on the properties of SBR and clay nanoparticles,three types of compatibilizers, maleic anhydride grafted ethylene-propylene diene rubber (EPDM-g-MAH), acrylonitrile-butadiene rubber (NBR) and epoxidized natural rubber (ENR50) have been used. The nanocomposites have been compared together from view point of their curing behavior, rheological and mechanical properties. The developed microstructure and dynamics of the macromolecular chains in proximity of the clay nanolayers have been characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and melt rheo-mechanical spectroscopy (RMS). Curing behavior of the prepared nanocomposites has been evaluated using a rubber curing rheometer. EPDM-g-MAH and ENR50 showed to enhance the interactions between SBR chains into clay tactoids much stronger than NBR as a compatibilizer. These were consistent with the dynamic mechanical thermal analysis (DMTA) data as well as macroscale mechanical properties tested on the samples.