摘要
In this study,three sorts of polyols were successfully synthesized from castor oil using a Dean-Stark quick,eco-friendly and high-efficiency method.For this purpose,castor oil was epoxidized in the presence of two types of catalysts includingγ-alumina and formic acid,named as ECOAl and ECOF,respectively.Epoxidized castor oils were then characterized by use of hydrogen nuclear magnetic resonance(H-NMR)and oxirane oxygen content analysis.The relative percentages of conversion double bond to oxirane were obtained 96% and 74% for ECOAl and ECOF,respectively.Ring opening reaction of ECOAl was performed by two types of saponified castor oil as well as castor oil in a system equipped with Dean–Stark apparatus.The synthesized polyols were characterized by attenuated total reflectance-Fourier transform infrared spectroscopy(ATR-FTIR),gel permeation chromatography(GPC),differential scanning calorimetry(DSC),viscometer and OH number evaluation.The material obtained in this research is a candidate to be intended in synthesis of polyurethane for coating applications.
