US 12,478,924 B2
Method for preparing durably hydrophilic and uniform-pore ultrafiltration membrane
Chunrui Wu, Tianjin (CN); Jingguo She, Tianjin (CN); Haifu Gao, Tianjin (CN); Xiaole Chen, Tianjin (CN); Ziping Song, Tianjin (CN); and Xiaolong Lv, Tianjin (CN)
Assigned to TIANGONG UNIVERSITY, (CN)
Filed by TIANGONG UNIVERSITY, Tianjin (CN)
Filed on Jul. 21, 2022, as Appl. No. 17/814,107.
Claims priority of application No. 202110843413.6 (CN), filed on Jul. 26, 2021.
Prior Publication US 2023/0035042 A1, Feb. 2, 2023
Int. Cl. C08J 9/14 (2006.01); B01D 61/14 (2006.01); B01D 67/00 (2006.01); B01D 69/02 (2006.01); B01D 69/06 (2006.01); B01D 69/08 (2006.01); B01D 71/30 (2006.01); B01D 71/34 (2006.01); B01D 71/82 (2006.01)
CPC B01D 67/0011 (2013.01) [B01D 61/145 (2013.01); B01D 67/00165 (2022.08); B01D 69/02 (2013.01); B01D 69/06 (2013.01); B01D 69/08 (2013.01); B01D 71/301 (2022.08); B01D 71/34 (2013.01); B01D 71/82 (2013.01); C08J 9/142 (2013.01); B01D 2323/02 (2013.01); B01D 2323/30 (2013.01); B01D 2325/36 (2013.01); C08J 2203/12 (2013.01); C08J 2327/06 (2013.01)] 11 Claims
 
1. A method for preparing a durably hydrophilic and uniform-pore ultrafiltration membrane, the method comprising the steps of:
a) combining a polymer membrane material with reactive sites, reactive active hydrophilic molecules having hydrophilic chains, a membrane-forming porogen, and a solvent at constant temperature under conditions suitable to dissolve the polymer membrane material and to graft the reactive active hydrophilic molecules to the reactive sites, to derive a hydrophilized polymer solution having the polymer membrane material dissolved therein, with the hydrophilic chains of the reactive active hydrophilic molecules grafted to the reactive sites;
b) introducing the hydrophilized polymer solution into a coagulation bath to initiate a crosslinking reaction among the hydrophilic chains grafted to the reactive sites to form a hydrophilized polymer solution have a crosslinked network; and
c) performing a dry-wet phase separation process upon the hydrophilized polymer solution having a crosslinked network to produce an ultrafiltration membrane, the ultrafiltration membrane having an improved membrane-pore structure due to the crosslinked network synergistically restricting both the movement of polymer chains and the formation and growth of micelles during the dry-wet phase separation process.