MEMBRANE FORMATION OF SULFONATED POLYPHENYLENESULFONE AND ITS APPLICATIONS IN ORGANIC SOLVENT NANOFILTRATION

Abstract

Sulfonated materials have been applied in many membrane applications due to their high electrical conductivity, good chemical stability, hydrophilicity and low fouling propensity. The fixed charged groups and hydrophilic nature not only endow sulfonated polymers with superior physicochemical properties for membrane applications but also significantly change the membrane formation process. The rheological properties, phase separation behavior and molecular-level interactions of polyphenylenesulfone (PPSU) and sulfonated PPSU (sPPSU) polymers were investigated. In addition, by incorporating additive (i.e., polyethylene glycol) into dope solutions, phase separation and membrane properties of the sPPSU membranes can be manipulated. The good chemical resistance and permeation properties of sPPSU makes it a good candidate for organic solvent nanofiltration (OSN) applications. Through electrostatic interactions, chemical crosslinking and bioinspired coating, various sPPSU OSN membranes were fabricated. The fabricated sPPSU membranes demonstrate superior separation performances in the OSN tests and show promising prospects for industrial separation applications.