Preparation and thermomechanical characterization of polyurethane rigid foam – silica nanocomposites

Nowadays polyurethane foams (PUF) are used in many applications according to their versatile properties. Rigid PUF is a highly consumed product e.g. in construction and heat insulation systems because they have better thermal properties than do thermoplastic foams or other common insulation materials. Their low thermal conductivity is due to a unique combination of blowing agent properties, cell size, and closed cell morphology. Silica (SiO2) has been widely employed to create high-performance or high-functional materials over the last few decades. In this research rigid polyurethane foams were doped with nano silica [1-4]. Coupling agent and nano silica were reacted to produce a nano sized complex. The characterized complex was dispersed in polyol by ultrasonification technique. Foam samples containing 1–3 wt% modified nano silica were prepared and their thermomechanical characteristics investigated by several methods e.g. DMA, TMA, TGA, SEM and tensile test. Improvements on thermal and mechanical properties were observed due to addition of nano silica complex