Viscometry of Isothermal Urethane Polymerization

The viscosity values of Indian Space Research Organization's (ISRO) hydroxyl terminated polybutadiene (HTPB) at various temperatures, the isothermal viscosity changes during the curing reaction of ISRO-HTPB with dlisocyanatotoluene (TDI) with and without catalyst and with a filler, calcium carbonate have been studied. The effect of temperature on this curing reaction is determined. The viscosity-time profile has shown an anomalous behavior and an explanation is put forward on the basis of polyurethane-HTPB, TDI mixture interaction. The viscosity-time profiles are drawn using normalized coordinates, which is helpful to compare the relative viscosity build up over relative periods. Urethane polymers have been under active develop-ment in industries since inception because of their versa-tile properties. Urethane elastomers and thermoplas-tics are two major types of raw materials which are finally fabricated into desired products: Casting is a manufacturing technique for producing the above two classes, from initial liquid reactants to final solid poly-mer. Before casting, the reactive components have t