摘要

To enhance the ablation performance and mechanical strength of silicone rubber (SR), pristine multiwalled carbon nanotubes (MWNTs) were dispersed in the polymer matrix using dispersion kneader and two roller mixing mill. Electrical resistivity (100300 degrees C) was reduced with increasing filler concentration in the host matrix due to the presence and even dispersion of the nanofiller in the rubber matrix. The SR nanocomposite (1 wt % filler contents) has 28% better thermal stability and 100% improvement in the ultimate tensile strength is achieved as compared with the pristine polymer matrix counterpart. Oxy-acetylene torch was used to evaluate the ablation rates, % char yield, and backface temperature evolution at the back facet of nanoablators during the flame exposure for a specific duration. Ablation performance of the fabricated ablative nanocomposites was enhanced with increasing nanotubes concentration in the polymer matrix. Thermal stability and heat quenching ability of the SR nanocomposites were gradually augmented with increasing filler loadings in the host matrix. Porous silica char, polymer pyrolysis, char composition, and uniform dispersion of MWNTs in the rubber matrix were also analyzed using scanning electron microscopy and energy dispersive spectroscopy.

  • 出版日期2013-5-15