P(MA-AMPS)/PVA@SiO2 hybrid hydrogel coated stainless steel mesh for effective separation of stabilized oil-in-water emulsions under gravity

The superhydrophilic/underwater superhydrophobic membrane offers unique advantages in effectively sepa-rating oily wastewater. However, the development of membrane materials that can efficiently separate emulsions only under gravity is still a challenge. A crosslinked network copolymer P(MA-AMPS) was synthesized by radical polymerization of N, n-methylenebisacrylamide (MBA), methacrylamide (MA) and 2-acrylamide-2-methylpropa-nesulfonic acid (AMPS) initiated by potassium persulfate. Then polyvinyl alcohol (PVA) and nano-SiO2 were inserted to the crosslinked polymer system in order to prepare a P(MA-AMPS)/PVA@SiO2 hybrid hydrogel. The hybrid hydrogel can be sprayed on the surface of stainless steel mesh (SSM) by a simple spraying method, so as to achieve superhydrophilicity/underwater superoleophobicity. The oil-water emulsion permeation flux reached more than 352.94 L & BULL;m � 2 & BULL;h-1, while xhibiting a more than 99.5 % separation efficiency under gravity. The anti-fouling tests demonstrated that the membrane exhibited outstanding anti-fouling performance. Moreover, the combination of stable semi-interpenetrating networks and nanoparticles made the membrane exhibit excellent stability and durable separation ability in complex physicochemical environments.

Automated summary

A hybrid hydrogel, prepared by synthesizing a crosslinked network copolymer P(MA-AMPS) and introducing polyvinyl alcohol (PVA) and nano-SiO2, exhibited superhydrophilicity/underwater superoleophobicity when sprayed onto a stainless steel mesh (SSM). The membrane achieved a permeation flux of over 352.94 L…•m � 2 •h-1 and a separation efficiency of over 99.5% for oil-water emulsions under gravity. It also demonstrated excellent anti-fouling performance and stability in complex physicochemical environments due to the combination of stable semi-interpenetrating networks and nanoparticles.