Synthesis of Tung Oil Monoglyceride

Tung oil monoglyceride (TOM, also called eleostearic acid monoglyceride, EAM) is a derivative of a Chinese renewable natural resource Tung oil and it is a potential monomer for polyurethane which can improve the performances of polyurethane coating. The synthesis of TOM by esterification of eleostearic acid and solketal with catalyst p-toluenesulfonic acid was investigated. Experimental results showed that the suitable synthetic conditions for TOM were as follows: a. for the esterification of eleostearic acid and solketal, with regard to eleostearic acid 0.02 mol with concentration 0.5 mol/L, mole ratio of eleostearic acid to solketal 1:1.5, catalyst p-toluenesulfonic acid dosage 5% (wt, calculated by eleostearic acid), dehydrating agent xylene, and reaction time 3 h under refluxing. The conversion of eleostearic acid peaked at 99.1% under the optimal conditions and the intermediate, solketal eleostearate was obtained. b. after deprotection under acidic condition for 4 h at 35 °C to remove protection agent acetone which was employed in the synthesis of solketal, the product TOM would obtained with yield 93.6%.