Synthesis and carbene-insertion preparation of hydrophobic natural polymer materials for rapid and efficient oil/water separation

Abstract

In response to frequent oil spills and increasing discharges of oily wastewater, a variety of materials and methods have been developed to treat with oil–water mixtures. In this paper, a simple and versatile method to modify a broad spectrum of natural polymer surfaces (wood aerogel, pulpboard, filter paper, cotton cloth, electrospinning gelatin film, ultrafine polypropylene fiber) was reported. This modification was based on aryl diazo compounds with hydrophobic functional groups as precursors, which were thermally activated to generate highly active carbene intermediates and induce the X-H (X = O, C, …) insertion reaction on the surface of substrates. The success of surface modification was demonstrated by the irreversible changes of the surface properties and the application on multi-behavior oil/water separation. Moreover, according to the Owens-Wendt-Rabel-Kaelble method, the influence of the dispersion force and the polar force on various material surfaces was given to explore the separation mechanism. This one-step modification provides a facile and efficient strategy to achieve renewable, biodegradable, and environmentally friendly materials and surfaces with low surface energy, which offers considerable potential applications on disposal of oil pollution in the environment.