公开(公告)号：US09458292B2

公开(公告)日：2016-10-04

申请号：US14780310

申请日：2014-03-24

申请人： NOF CORPORATION

发明人： Hiroki Yoshioka ,  Shingo Kimura ,  Midori Hirai

IPC分类号： C08G65/34 ,  C08G65/30 ,  C08G65/333

CPC分类号： C08G65/34 ,  C08G65/30 ,  C08G65/333

摘要： A method for purifying a polyethylene glycol compound having one amino group, which includes (A) preparing an aqueous solution of the compound having a pH of 1 to 5, (B) an extracting step of mixing the aqueous solution with a mixed organic solvent to cause layer separation into organic and aqueous layers, wherein a ratio of an organic solvent I is 25 to 65% by mass and a ratio of an organic solvent II is 75 to 35% by mass, the organic solvent I is selected from an aromatic hydrocarbon and an ester, the organic solvent II is a halogenated hydrocarbon, and a mixing ratio Y of I to II, temperature T (° C.) at mixing, and molecular weight M of the compound satisfy the following relationship: 1.9×10−6M+0.09≦Y−0.015T≦−1.4×10−6M+0.44 and (C) recovering the compound from the aqueous layer.