| 摘要 |
PURPOSE: Provided is a method for preparing polyether-polyol comprising tetrahydrofuran units having a narrow molecular distribution, useful for elastic materials in the chemical industry. CONSTITUTION: The method for preparing polyether-polyol having a narrow molecular distribution comprises subjecting polyether-polyol(A) represented by the formula of HO-£(CH2)40|n-£(CR1R2)pO|q-H and having an average molecular weight of 500 to 4,500 to selective fractionation extraction using an aqueous solution(C) containing 15-70 wt% of sulfuric acid at a temperature from room temperature to 100 deg.C so as to obtain a low-molecular weight fraction, wherein the amount and concentration of the aqueous sulfuric acid solution based on those of the total organic layer are determined according to the molecular weight and molecular weight distribution of the target polyether-polyol to be extracted. In the above formula, R1 and R2 ae the same or different and each represents H or a linear or branched C1-C5 alkyl, n is a positive integer, p is an integer of 1-8, and 1 is 0 or a positive integer.
|
