Ablation, thermal stability/transport and mechanical investigations of modified nanokaolinite impregnated acrylonitrile butadiene rubber composites

Abstract

Modified nanokaolinite was uniformly dispersed in acrylonitrile butadiene rubber using dispersion kneader and two roller mixing mill. In order to evaluate ablation characteristics of the fabricated composites, high-temperature ablation testing was carried out. The peak incorporation of nanoclay in the rubber matrix has enhanced the ablation resistance up to 97% and reduced the temperature elevation at the back face of the nanocomposite up to 51% during the 200s oxy–acetylene flame exposure on the surface of the ablator. Thermogravimetric and differential thermal analyses elucidate the thermal endurance improvement with increasing filler contents in the polymer matrix. Thermal conductivity and thermal impedance of the composite specimens were evaluated on the domestically manufactured thermal conductivity measuring apparatus. It is scrutinized that the former property reduced up to 49% at and the subsequent characteristic of the rubber composite is elevated up to 43% at 373 K with the 30 wt% incorporation of the nanoclay into the base rubber composition. Mechanical properties of the acrylonitrile butadiene rubber composite specimens were significantly enhanced with increasing filler introduction into the host matrix. Porous char morphology, polymer pyrolysis and composition of the ablated samples were analyzed using scanning electron microscopy and energy dispersive spectroscopy analyses.