초록 |
The polycarbonate polyols were produced by starter and monomer with carbon dioxide (CO2) catalyzed by double metal cyanide (DMC) catalysts, prepared by reacting aqueous zinc chloride (II) and potassium hexacyanocobaltate (III) with various complexing agents (CAs). The hydroxyl functionality of polycarbonate polyols is successfully controlled by the type of poly (propylene glycol) (PPG) starter. The higher functionality of PPG, the higher CO2 selectivity of polycarbonate polyol. The resultant polycarbonate polyols produced in the presence of PPG starter were analyzed by using nuclear magnetic resonance spectroscopy, gel permeation chromatography, thermogravimetric analysis, differential scanning calorimetry and hydroxyl value. |