Krushna Chandra Pradhan and P. L. Nayak
Polyurethanes (PUs) are one of the most versatile classes of materials today and their demand as a high performance industrial material continues to grow. The wide application of Pus necessitates understanding the chemistry and structural elements that improve the thermal stability and flame retardancy as these are important prerequisites to obtain tailor-made products for high performance applications such as in aggressive environments. . In the present research program, some polyurethane nanocomposites have been prepared from a natural oil like castor oil using HMDI and organically modified clay. Polyurethanes and their nanocomposites have been characterized by using some sophisticated methods like FTIR, SEM, XRD, TGA, and mechanical testing. Hydrophobic nanoparticles and nanocomposite of 1,4-hexamethylene diisocyanate (HMDI)-modified PU nanoparticles (PU-NPs) have been synthesized at ambient temperatures. The platelet-like nanocrystals become pseudospherical after modification with HMDI and the size increases or decreases depending on diisocyanate concentration compared to the ungrafted particles as revealed by scanning electron microscopy (SEM) results. The obtained nanocrystals were characterized by means of the FT-IR and X-ray diffraction (XRD) techniques
