Mechanical and Morphological Properties of Waste Short Nylon Fibers and Nanoclay Reinforced NR/SBR Rubber Nanocomposites

Natural rubber and styrene butadiene rubber (NR/SBR) reinforced with short nylon fibers along with nanoclay (Cloisite 15A) hybrid composites were prepared in an internal and a two roll-mill mixer by a three-step mixing process. The effects of fiber content at a constant loading of 3 wt% nanoclay were studied on the microstructure, mechanical and morphological properties of the prepared nanocomposites. The adhesion between the fiber and the rubber was enhanced by the addition of a dry bonding system consisting of resorcinol, hexamethylene tetramine and hydrated silica (HRH). The curing characteristics of the composites were determined and subsequently vulcanized at 150°C using a hot press. It was observed that the cure time and swelling index of the composites decreased while maximum torque, and cure rate increased with increasing of short fiber and nanoclay contents. The structure and fracture surface morphology of the nanocomposites were characterized using X-ray diffraction, scanning electron microscopy. X-ray diffraction results of nanocomposites indicated that the interlayer distance of silicate layers increased. The mechanical properties (tensile, tear strength, elongation-at-break and hardness) ofnanocomposites containing virgin and waste fibers in the longitudinal direction are compared.