Liquefaction of corn bran (CB) in the presence of alcohols and preparation of polyurethane foam from its liquefied polyol

Liquefied corn bran (CB)-based polyol was obtained by the liquefaction of CB in the presence of a poly(ethylene glycol) (PEG400)/glycerol mixed solvent. The effects of liquefaction parameters on the degree of liquefaction were evaluated. The catalyst content and solvent/CB ratio have a greater influence on the percent residue than does the reaction temperature. Polyurethane foams were successfully prepared from the liquefied CB-based polyol. Molecular weights of CB-based polyol have no effect on the reaction time, and its hydroxyl numbers and viscosities were suitable for the preparation of foam. Furthermore, the acid value increased to about 34 during the liquefaction. The densities and mechanical properties of the foams showed comparable values to those of conventional polyurethane foams. The amount of additive (PCL303) in the liquefied CB-based polyol had a significant effect on the properties of the resulting foams. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 319–325, 2000