Preparation and curing reaction kinetics of liquid crystalline epoxy resin/montmorillonite nanocomposites

The liquid crystalline epoxy resin/organoclay nanocomposites were prepared based on 4,4'-diglycidyloxy biphenyl (BP) with the rigid-rod mesogen unit, sulfanilamide (SAA) and the organoclay (93A) modified with methyl, dihydrogenatedtallow ammonium ion. It was found that the organoclay could be intercalated by BP and the layer spacing increased from 2.3 nm to 3.7 nm. The XRD results showed that the exfoliated nanocomposite could be formed when the content of the organoclay was 2 percent. The hybrid with 10 percent of 93A formed the intercalated nanocomposite and a blend of two types of nanocomposites were formed with 5 percent of 93A. POM observation showed that the organoclay retarted the formation of a fan-shape smectic liquid crystalline phase as in pure resin system. The curing reaction of BP was studied by differential scanning calorimetry (DSC) at various heating rates, and the active energy at different conversion was calculated with Kissinger-Akahira-Sunose method. The results showed that the addition of organoclay decreased the active energy at the early curing reaction and promoted the curing reaction of the liquid crystalline epoxy resin.