Studies on Bio-Based Polyurethanes-Thermal and Mechanical Properties

Cardanol, a major ingredient of Cashew Nut Shell Liquid (>87%) is a long chain meta-substituted phenol. It reacts with furfural in different mole ratios in the presence of dicarboxylic acid as catalyst to give novolac resin. The characterized cardanol-furfural resin can be properly modified to a high molecular weight hydroxyalkylated derivative, a nucleophilic compound (polyol) through epoxidation followed by hydrolysis.Polyurethanes were formulated by reaction of the hydroxylalkylated cardanol-furfural resin with the commercially available polyol, polypropylene glycol-1200(PPG-1200) and 4, 4'- Diphenylmethane diisocyanate/Toluene diisocyanate. These polyurethanes were characterized with respect to their resistance to chemical reagents and mechanical properties such as tensile strength, percentage of elongation and hardness. Thermal properties were characterized by Thermo gravimetric Analysis (TGA).