The effect of solvent on the mechanical properties of polyhedral oligomeric silsesquioxane (POSS)–epoxy nanocomposites

Abstract

The present study investigated the influence of different compatibilizer on the dispersion of polyhedral oligomeric silsesquioxane (POSS). The effect of POSS dispersion in the epoxy resin in terms of mechanical, and thermal properties were reported. The three solvent used to disperse POSS in this work are ethanol, acetone, and toluene. The POSS was initially dispersed in the solvent followed by an addition in the epoxy resin by systematically varying the weight fraction from 0.5 to 8 wt%. Mechanical properties of nanocomposites were characterized in terms of elastic modulus, and fracture toughness. The obtained result illustrates that nanocomposites prepared by polar solvent dispersion such as ethanol showed an increase in values of elastic modulus and fracture toughness value. The increase in the modulus and fracture toughness value is due to the better interaction between POSS and ethanol disperse the POSS uniformly in the epoxy resin while avoiding the agglomeration. However, nanocomposites prepared by nonpolar solvent does not show substantial change in the mechanical properties. Fractured surface morphology was studied using scanning electron microscopy. Differential scanning calorimetry and dynamic mechanical analysis illustrates that with better POSS dispersion value of glass transition temperature (Tg) increased. Fourier transformation infrared spectroscopy showed that POSS completely interacted with the epoxy resin and no phase separation was observed.