| 摘要 |
PURPOSE: To obtain a water-soluble maleic diester which is used as a water-soluble monomer or a resin modifier by allowing a maleic diester to react with a specific alcohol in the presence of an ester-interchanging reaction catalyst in high yield without neutralization and removal by washing of the catalyst. CONSTITUTION: (A) A compound of formula I (R<3> is methyl, ethyl) is allowed to react with (B) a compound of the formula: R<2> O(R<1> O)n H [R<1> is a 1-4C alkylene; R<2> is a 1-8C (branched) alkyl; n is 1-3] in the presence of (C) an ester- interchanging catalyst such as dibutyltin oxide, dioctyltin, tetrabutyl titanate, to give the objective maleic diester. In a preferred embodiment, the amount of the component C is 0.0001-1wt.%, particularly 0.001-0.2wt.% and the reaction temperature is set to 70-300 deg.C, particularly to 80-230 deg.C. |
