| Silicone rubber (SR) is one of the most important types of high performancerubbers that have been used in high temperature applications owing to their excellentthermal stability. Many investigations on the thermal stability properties of the SRbased nanocomposites have been reported. Carbon nanotubes (CNTs) with its specialstructure and excellent performance, has potential applications in many fields.Surface functionalization of multiwalled carbon nanotubes (CNTs) was carried outby grafting of polyhedral oligomeric silsesquioxane (POSS) via amide linkages. ThePOSS functionalized CNTs (CNTs-POSS) was introduced into silicone rubber (SR)matrix to prepare CNTs-POSS/SR nanocomposites. Fourier transformed infraredspectroscopy(FTIR), Raman microscopy, transmission electron microscopy(TEM), X-ray photoelectron spectroscopy(XPS) were used to confirm that POSS was decoratedon the surface of CNTs and the weight gain was determined by thermogravimetricanalyses (TGA). The effects of the CNTs’ surface treatment on the dispersibility ofCNTs-POSS in the SR matrix, the mechanical, electrical and thermal properties of theobtained nanocomposites were also studied. The results indicated that CNTs-POSSwas well dispersed into SR matrix. The interfacial interactions between CNTs-POSSand SR was stronger than that between CNTs-COOH and SR. Thermal conductivityof CNTs-POSS/SR was improved compared to the controlled samples, and thevolume resistivity remain at a higher value compared with CNTs-COOH/SR Themechanical properties of CNTs-POSS/SR nanocomposites before and after thermalaging were higher than those of CNTs-COOH/SR composites. TG-FTIR analysisrevealed that the grafted POSS on CNTs improved the thermal oxidative stability ofSR composites and hindered the thermal degradation of silicone rubber to cyclicoligomers. |
