Soy-based polyols from oxirane ring opening by alcoholysis reaction



A screening study was conducted to identify a catalyst that promotes epoxy ring opening of full epoxidized soybean oil (ESBO) avoiding side reactions at low concentration and temperature. Six catalysts different catalyst: formic acid, phosphoric acid, POLYCAT® 5, p-toluenesulfonic acid monohydrate, POLYCAT® SA-1, and DABCO® BL17 were evaluated in terms of acid number, oxirane oxygen content, and color analyses. p-Toluenesulfonic acid shows a particular behavior that promotes the reaction resulting in a maximum oxirane oxygen content reduction; low acid number and color index compare to the others catalyst. To create an alkoxy hydroxy ESBO molecule, ESBO was combined with methanol and ethylene glycol using 0.5% by wt of p-toluenesulfonic acid at 130, 150, and 170°C for different reaction times. Optimal conditions for oxirane ring opening by alcoholysis reaction were determined varying temperatures and reaction times. FTIR spectrum confirmed the emergence of hydroxyl groups in the alkoxy hydroxy ESBO polyol sample. The polyol sample G was characterized in terms of its hydroxyl number and its potential of replacing up from 50–100% of the petroleum-based polyol in waterborne rigid polyurethane foam application. All polyurethanes foams were evaluated to determine their thermal conductivity, density, and compressive strength properties. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009