Abstract
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.
•Waxy corn starch has been utilized as a substitute of 1,4-BDO at different moles ratio.•Reaction of starch in the PU was monitored by FTIR spectroscopy.•Structural characterization was done by using NMR spectroscopy.•GPC was used to confirm the role of starch as a chain extender.•Thermal degradation behavior of PUs was influenced by using starch.