The thermal properties of rectorite/thermoplastic polyurethane nanocomposites

OREC (organic rectorite clay)/TPUR (thermoplastic polyurethane) nanocomposites were prepared via melt blending. There were four temperature ranges in the extruder. The temperature was 120°C at the extruder head, and was 130°C, 140°C and 120°C in the former, middle and back parts, respectively. OREC was prepared with natural rectorite and dodecanic quaternary ammonium salt through ion-exchange. The nanoscale dispersibility of the OREC layers in the TPUR matrix was revealed by using transmission electron microscopy (TEM). The thermodynamic mechanical analysis (DMA), thermogravimeric analysis (TG), oil-resistant and hot air aging of nanocomposites were also measured. The results showed that the largest storage modulus is 7 times more than that of pure TPUR's, and the largest loss moduli is 4 times more than that of pure TPUR's . The other thermal properties of the composites have been enhanced as compared with those of the TPUR matrix due to the well-dispersed OREC layered particles in the OREC/TPUR nanocomposites. When the content of OREC is 2% , the initial degradation temperature of the composite is 15°C higher than that of the pure TPUR, and the ratio of the residual tensile strength to the original strength is over 86% after oil treatment for 168 h, or air aging at 120°C for 72 h.