| 摘要 |
<P>PROBLEM TO BE SOLVED: To separate impurities from a carboxyl group-containing polyoxyethylene derivative having a molecular weight of 2,000-100,000. <P>SOLUTION: A polyoxyethylene derivative is dissolved by using toluene, xylene, benzene, ethyl acetate or butyl acetate in an amount of five times by mass the amount of the polyoxyethylene derivative to form a solution. An inorganic absorbent including at least one of an oxide and a hydroxide of at least one element selected from the group consisting of magnesium, silicon, and aluminum is added to the solution in an amount of 0.5-10 mass times the amount of the polyoxyethylene derivative to form a slurry. The slurry is agitated at a temperature of 25°C or higher. The resulting slurry is filtered and toluene, xylene, benzene, ethyl acetate or butyl acetate is added to the filtered cake to further perform filtration, and methanol, ethanol or 2-propanol is added to the filtered cake in an amount of five mass times the amount of the polyoxyethylene derivative to perform filtration, and the polyoxyethylene derivative is recovered from the obtained filtrate. <P>COPYRIGHT: (C)2011,JPO&INPIT |
