Utilization of waxy corn starch as an efficient chain extender for the preparation of polyurethane elastomers.

Waxy corn starch modified polyurethane elastomers were synthesized by step growth polymerization reaction between NCO-terminated prepolymer and chain extenders (1,4-butanediol/starch). Isophorone diisocyanates (IPDI) was reacted with hydroxyl terminated polybutadiene (HTPB) to synthesize prepolymer that was reacted with different moles of 1,4-butanediol (1,4-BDO) and starch to produced five samples of polyurethane. These specimens were analyzed by Fourier transformed infrared (FTIR) and proton Nuclear Magnetic Resonance (1H NMR) spectroscopy to determine the structural information. However, role of starch as chain extender was examined by gel permeation chromatography (GPC). Additionally, starch increased the thermal stability of PUs as compared to the conventional chain extender (1,4-BDO). Over all, this work has been designed to develop biodegradable polyurethanes that could be used in biomedical systems.