公开(公告)号：US11267925B2

公开(公告)日：2022-03-08

申请号：US16626736

申请日：2017-06-30

Applicant: Dow Global Technologies LLC

Inventor： Jing Ji ,  Felipe A. Donate ,  Xin Jiang ,  Cheng Shen ,  Kazuyuki Hasegawa ,  Jacob Crosthwaite ,  Rebecca J. Wachowicz

IPC: C08G18/08 ,  C08G18/12 ,  C09D7/20 ,  C08G18/24 ,  C08G18/34 ,  C09D175/04

Abstract: A prepolymer comprising acid functionality is made by a process comprising the step of contacting: (i) a di-isocyanate, (ii) a polyol containing an acid group, (iii) a polyol without an acid group, and (iv) a metal salt catalyst, the contacting conducted under reaction conditions and in a solvent consisting essentially of: (A) a dialkyl amide, and (B) optionally, an aprotic glycol ether. The prepolymer is useful in the preparation of water-based polyurethane dispersions, and certain of the solvent blends consisting essentially of a dialkyl amide and an optional aprotic glycol ether are azeotropic or pseudo-azeotropic.