Synthesis of β-CD dimer cross-linked self-healing organogel and its coated mesh for oil-water separation

With the continuous advancement of global industrialization, oil-water separation materials that combine efficient separation and resource recovery have become an urgent issue in the fields of environmental science and engineering in crude oil extraction, oil-containing industrial production and wastewater discharge. To address the limitations of current separation membranes, such as susceptibility to damage and inadequate durability during operation, this study reports the synthesis of a self-healing organogel based on β-cyclodextrin dimers and dynamic phenylboronate ester bonds. This material was coated onto a nonwoven fabric substrate via a dip-coating and photo-polymerization process, yielding a self-healing oil-water separation mesh (SHSM) exhibiting superoleophilicity and underoil superhydrophobicity. The structural characteristics of the SHSM and its surface coating were characterized using scanning electron microscopy (SEM), proton nuclear magnetic resonance spectroscopy ( 1 H NMR) and Fourier-transform infrared spectroscopy (FTIR), the separation performance and self-healing capability of SHSM were systematically evaluated. Experimental results demonstrate that the SHSM achieves separation efficiencies exceeding 99.5% for various oil-water mixtures, with an oil flux reaching 4.30×10⁴ L·m⁻²·h⁻¹. Even after mechanical damage or repeated use, the SHSM can restore its structural integrity and functional performance through the reformation of dynamic boronate ester bonds, thereby significantly extending its service life. This research offers a novel strategy for the development of highly efficient and durable oil-water separation materials. Download: Download high-res image (232KB) Download: Download full-size image A β-cyclodextrin dimer coating enables self-healing, superoleophilic, underoil superhydrophobic non-woven fabric for oil-water separation.