Probing the Properties of Nanocomposites Synthesized from Aramid and Surface-Modified Clay
Nanocomposites were prepared by the inclusion of layered silicates into the aramid matrix via a solution intercalation technique. Polyamide was synthesized by reacting 4,4′-oxydianiline with isophthaloyl chloride and then end-capping with carbonyl chloride end groups using excess diacid chloride. The compatibility between the two phases was obtained through surface modification of montmorillonite with long-chain alkyl diamine. The nanocomposites were characterized with regard to structural, morphological, mechanical, thermal, and water absorption measurements. These investigations confirmed the formation of delaminated and disordered intercalated nanostructures at different clay loadings. Mechanical properties were significantly enhanced relative to pristine polyamide, even with the addition of only 2 wt-% of nanoclay. Thermal decomposition temperatures of the nanocomposites were in the range 300–450°C. Glass transition temperature data exhibited improvement (123°C) up to 16 wt-% addition of organoclay. Water absorption of the neat aramid was rather high (5.7%), but decreased with augmenting clay content.