The fabrication of porous hollow polysulfone microspheres with PEG as a porogen for methylene blue adsorption

Abstract

A porous hollow polysulfone (donated as PHPSF) microspheres were prepared by non-solvent-induced phase separation using PEG as a porogen. The influence of the molecular weights (Mw) of PEG on the morphology and porous structure of the microspheres were investigated. As the Mw of PEG increasing from 600 to 10,000 g·mol–1, the viscosity of the system increases, leading to the increase of the viscosity difference between the dispersed phase and the continuous phase, and a delay in phase separation. Hence, the diameter and shell thickness of the obtained microspheres increase with the porosity reducing. Moreover, when the Mw of PEG is below 4000, the low |Δδ| between PEG and solvent is conducive to the formation of microporous structure with narrow pore distribution. The as-prepared PHPSF microspheres exhibit a separation efficiency of 6 times for MB than that of the original PSF microspheres. In addition, a reusability of 5 times of PHPSF is achieved even in the harsh acid or alkali condition. These results clarify the relationship between the different Mw of PEGs and microspheres morphology. Therefore, this kind of PHPSF microspheres holds a promising for the water organic pollution treatment.