Facile preparation and thermal degradation studies of graphite nanoplatelets (GNPs) filled thermoplastic polyurethane (TPU) nanocomposites

A facile method with the advantage of using only one single solvent throughout the whole processing was introduced to prepare graphite nanoplatelet (GNP) filled thermoplastic polyurethane (TPU) nanocomposites. Morphological studies showed that the employed method could provide the uniform dispersion of GNPs in the TPU matrix. Storage modulus of the nanocomposites was increased with increasing GNP content, and the improvement was more obvious at temperatures below the glass transition temperature (Tg) of TPU. For the nanocomposite that contains 3.9 vol% (the maximum loading employed in this study) of GNP, it still showed a long elongation at break of over 600%. Thermogravimetric analysis (TGA) showed that the incorporation of GNPs could improve the thermal stability of the nanocomposites. In addition, cone calorimetry results showed that the GNPs could act as intumescent flame retardant and significantly reduced the heat release rate (HRR), thus improved the flame retardancy of the TPU matrix.