JET-COOKED STARCH OIL COMPOSITE IN POLYURETHANE FOAMS

A new jet-cooked starch-oil composite has been blended with a polyeste r polyol and then reacted with isocyanate to give a polyurethane foam. Infrared spectroscopy and microscopy have been used to examine the re sultant products. Infrared spectra have shown the products contain the urethane structures and Light and electron microscopy have shown the differences in the cell wall structures and networks of the foams when compared to the control foams. Inclusion of the starch-oil composite in the formulation resulted in increased viscosity of the reaction mix ture as well as a more irregular cellular structure and a rougher text ure of the cured foam. Larger cells were more abundant and there was m ore evidence of tearing during expansion. The scanning electron photom icrographs show the open-cell structure of both the control and blende d foams and their reticular network, which is more uniform in the cont rol. This examination provides insight into the foaming process and pr ovides information to make the necessary adjustments for acquiring the desired polymeric product. Incorporation of the starch-oil composite in polyurethane foams provides a new dimension of possibilities for en hancing their physical, functional, and environmental properties. (C) 1997 John Wiley & Sons, Inc.