The role of clay modifier on cure characteristics and properties of epoxy/clay/carboxylterminated poly(butadiene-co-acrylonitrile) (CTBN) hybrid

Epoxy/clay/carboxyl-terminated poly(butadiene-co-acrylonitrile) (CTBN) hybrids were prepared with two different organically modified clays. Octadecyl amine and trimethyl stearyl ammonium-modified nanoclays (Nanomer I. 30E and I. 28E, respectively) were used. The dispersion of the nanoclay in binary epoxy/clay and epoxy/clay/CTBN hybrid nanocomposites was investigated using scanning electron microscopy and optical microscopy, and the observed morphological details were explained by the prediction of solubility parameter for each component in the nanocomposites. The effect of clay modifier on cure characteristics of binary epoxy/clay and epoxy/clay/CTBN hybrid nanocomposites was studied using rheological analysis. Glass transition temperatures (T-g) and thermal stability of binary and hybrid nanocomposites were also measured. The reduced cross-link density via epoxy homopolymerization, the plasticizing effect of clay modifier/dissolved liquid rubber and the interfacial adhesion between the polymer and the clay platelets were found to affect the Tg of epoxy/clay/CTBN hybrid. In epoxy/clay/ CTBN hybrid, the thermal stability was mainly attributed to the presence of CTBN which hide the effect of clay modifiers.