Investigation of crystallization of polymer nanocomposites exposed to water

Abstract

This project investigates the effect of water and temperature on the crystalline phase of polyamide nanoclay nanocomposites. Experiment was carried out on Polyamide-6 (PA6) nanocomposites containing 0 wt%, 2 wt%, 4 wt% and 8 wt% of nanoclay. Nanocomposite films were immersed in water at elevated temperatures, i.e. 55 oC, 65 oC and 75 oC. After one day of immersion, FTIR analysis was carried out on the samples after drying and -to-α crystalline phase transition was observed. The infrared band 1200 cm-1 was used to determine the rate of -to-α crystalline phase transition. By assuming first order kinetics, the rate constants were determined for different nanocomposites. Results showed that at higher temperature, the rate of α crystals formed in the polymers was higher. The change in rate constant at different temperatures was used to determine the activation energy of the crystalline phase transition by applying Arrhenius equation. It was found that rate constants increased as temperature increased. Activation energy also increased with increasing clay content in the nanocomposites. Pure PA6 also exhibited high activation energy comparable to 8 wt% PA6 nanocomposites.