Facile hydrophilic modification of polydimethylsiloxane-based sponges for efficient oil-water separation

In this study, an eco-friendly fabrication process for the hydrophilic polydimethylsiloxane (PDMS)-based sponge was proposed with the assistance of sugar templates and poly(dimethylsiloxane-b-ethylene oxide) (PDMS-b-PEO) block copolymer additives. The effects of sugar loadings and sugar particle sizes on sponge structure and separation performance were investigated. Manipulating sugar loadings exhibited a unique control over the porosity of sponge, which further influenced the absorption capacity and oilwater separation speed. Additionally, the surface modification of PDMS sponge from hydrophobic/oleophilic to hydrophilic/underwater oleophobic was achieved by incorporating PDMS-b-PEO. Such modified sponge demonstrated an underwater oil contact angle of 154 degrees and a stable separation efficiency greater than 99.9% in the gravity-driven cycled filtration tests. The hydrophilic PDMS-b-PEO modified sponges highlighted herein reveal a promising potential for novel separation materials with energy-efficient and cost-effective features, which are ideal for oil spill clean-up events and wastewater treatment application. (C) 2021 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.

Automated summary

This study proposed an eco-friendly fabrication process for hydrophilic PDMS sponge, investigated the effects of sugar loading and particle size on sponge structure and separation performance. By controlling sugar loading, porosity of sponge could be adjusted, affecting absorption capacity and separation speed. Surface modification with PDMS-b-PEO transformed sponge from hydrophobic/oleophilic to hydrophilic/underwater oleophobic, showing potential for novel separation materials.