The curing behaviour and thermo-mechanical properties of core–shell rubber-modified epoxy nanocomposites

Abstract

This work investigates the effects of core–shell rubber (CSR) nanoparticles on the curing behaviour and thermo-mechanical properties of an epoxy using differential scanning calorimetry and dynamic mechanical thermal analysis approaches. Interaction between CSR nanoparticles and epoxy matrix is detected at a temperature of approximately 97°C in the curing process. This results in an increase in the glass transition temperature ( Tg) of the cured nanocomposites. Given the semi-dynamic curing schedule, the curing process of all the epoxy nanocomposites consists of an abrupt onset stage followed by a slow diffusion-controlled stage. Higher temperature is required to initiate the curing for the epoxy nanocomposites with higher loading of CSR nanoparticles. This is attributed to the physical changes caused by the addition of CSR nanoparticles, such as the increase in the viscosity and the reduction in the density of the reactive groups. The storage modulus of the epoxy decreases in the glassy region but remains constant in the rubbery region due to the incorporation of CSR nanoparticles.