Transparent and flame retardant PMMA nanocomposites

Poly(methyl methacrylate) (PMMA) nanocomposites containing an organoclay and triphenyl phosphate (TPP) were prepared by solution blending using a PMMA solution in methyl methacrylate (MMA) solvent. Exfoliated nanostructures were shown by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The optical transmittance of the PMMA nanocomposites decreased with an increase in the clay content. The improvement in the thermal stability of the PMMA nanocomposites was greater in air than in nitrogen. Nanocomposite formation brought about reductions of the peak heat release rate (PHRR), as measured by cone calorimetry. The combination of the nanoclay and TPP brought about a further decrease in the PHRR and an increase in the average specific extinction area (ASEA, related to smoke production). Copyright (C) 2008 John Wiley & Sons, Ltd.