Synthesis and Characterization of Poly (urethane-urea) based on Functionalized Polystyrene and MDI

Abstract

The poly(urethane-urea) based on α, Ω, hydroxy terminated polystyrene (OH-PSt-OH), 4,4’- methylenediphenyldiisocyanate(MDI) and three different diamines is prepared by a melt polymerization method. The length of the soft segmentis varied from 2310 to 9366 g/mol using MDI as a chain extender. The synthesized copolymer is characterized by viscosity measurements, FT-IR,temperature dependent FTIR,DSC, TGA,swelling ratio and solvent resistivity. The inherent viscosity of the polymeris found to be in the range of 0.5-2.3dL/g is suggesting that the polymerare of high molecular weight. Differential scanning colorimetry (DSC) data’sare confirming that the melting temperature of the polymer varies from 237°C to 263°C. From the temperature dependent FTIR, the crystallinity obtained for hard segment is around85%. The TGA data reveal that the polymer shows single stage decomposition center around 414°C.The solubility in chloroform and swelling ratio of the polymer depending on the concentration of the hard segment