LAUSR

A few novel metal-polymer (polyurethane-iron (PU-Fe)) nanocomposites were fabricated. First, the polyurethane (PU) polymer is synthesized from the ethylene glycol and iso-phorone di-isocyanate (as monomers) keeping the NCO/OH ratio at 1.2. The metal-polymer nanocomposites(PU/Fe) with 30 wt% of high-purity filler (Fe) powder of nano size were added during the polymerization process of PU in the reaction vessel. The formation of polyurethane (PU) was ascertained by the FTIR investigation of the -NCO, -OH, -NH and -C=O stretching vibrations. The XRD and FTIR study on the PU/Fe confirmed the presence and good interaction between Fe(0) and PU. Study of the effect of temperature and frequency on electrical characteristics of the nanocomposites, such as dielectric constant, loss tangent (tan δ), electrical impedance/modulus, etc., of composites has provided interesting results. It has been observed that, iron nanoparticles have significant effect on the above electrical properties of the nanocomposites. The iron-polyurethane nanocomposites can be used as biomaterials, self-cleaning materials and shape memory, and smart materials. The dielectric relaxation of these composites was also studied as a function of frequency from 1 kHz to 5 MHz. Detailed results were presented and discussed in the present communication.