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A novel castor oil-based polyols with fluorine-containing pendant groups (CO-FPOL) has been synthesized through ring-opening polymerization from castor oil (CO), propylene oxide (PO) and self-made 3-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoro-octyloxymethyl)-Oxirane (TDFOMO). The TDFOMO was synthesized from 3,3,4,4,5,5,6,6,7,7,8,8,8-Tridecafluoro-1-octanol (TDFOL) and Epichlorohydrin (ECH). Then, the CO-FPOLs further reacted with a 4,4′-diphenylmethane diisocyanate (MDI) to prepare a one-component fluorinated polyurethane coating (CO-FPUP). Strikingly, the fluorine content of CO-FPOL can be easily controlled, the thermal stability of CO-FPOL and CO-FPUP increased with the increasing of fluorine content. It was all found that with the fluorine content of CO-FPOL increasing from 0% to 17.72%, the static water contact angle of CO-FPUPs increased from 90° to 106°, and the static oil contact angle of CO-FPUPs increased from 20° to 54°. The XPS survey spectra revealed that the fluorine in the cured polyurethane would migrate to the surface easier due to the fluorinated pendant groups which moving easier between molecular chains. All the above results suggest that the introduction of fluorinated pendant groups in polyether polyol has great improvements in the thermal stability and the hydrophobic and oleophobic properties of polymer materials. [ABSTRACT FROM AUTHOR]

We demonstrate in this paper a super-hydrophilic and oleophobic green porous photothermal material based on wood fiber as a novel oil-repellent photothermal material for efficient solar vapor generation (WF-SP). WF-SP is an excellent light-absorbing material with the advantages of a porous nanostructure, super-hydrophilic, low thermal conductivity, high-temperature resistance, and oleophobicity. Based on these advantages, WF-SP exhibits good solar photothermal conversion performance with solar vapor generation efficiencies of 85.4%, 75.3%, and 70.2% at 1 kW m−2, 2 kW m−2, and 3 kW m−2 radiation intensities, respectively. The results provide new possibilities for the design and preparation of low-cost, green, and pollution-free photothermal materials with high solar thermal conversion efficiency for solar photothermal conversion vapor generation. [ABSTRACT FROM AUTHOR]

Hydrophobic and oleophobic materials have an important role in daily-life and industry. The hydrophobic and oleophobic property is mainly ascribed to the low surface energy materials and the roughness surface. The hydrophilicity and oleophobicity surface can be achieved by surface modification methods, such as electrodeposition, sol-gel process, chemical vapour deposition and spray deposition. In this paper, the properties of hydrophobic and oleophobic materials are introduced. The principles, characteristics and applications of surface modifications in hydrophobic and oleophobic materials are reviewed. [ABSTRACT FROM AUTHOR]

Several products are on the market to realize water-, oil-, and soil-repellent properties on textiles or textile-related materials. To make an adequate and fast rating of repellent properties of finished textiles, different drop tests according to AATCC and ISO standards are commonly used. For evaluation of the repellent properties of solid substrates against different liquids often contact angle measurements are performed. The aim of the work presented here is to determine and evaluate the repellent effects gained by the application of three different finishing agents on three different substrates, such as polyester fabric, artificial leather, and leather. The main questions are at that point: It is possible to gain similar repellent effects with the same finishing product applied on different substrates? Do the different testing methods lead to comparable results? Is there a relation to the repellency against everyday consumer products as red wine, ice tea, or coffee? This article should help the reader to evaluate different testing methods and the influence on common substrates. [ABSTRACT FROM AUTHOR]

In the present study, an attempt has been made to design an oleophobic surface through chemical graft copolymerization of methyl methacrylate (MMA) onto polytetrafluroethylene (PTFE) film. The PTFE films were grafted with MMA resulting in PTFE-g-MMA grafts using benzoyl peroxide (BPO) as initiator in aqueous media. Optimum conditions pertaining to maximum percentage of grafting were evaluated by varying time, temperature, initiator, and monomer concentration. The maximum graft yield 9.47% was obtained at [BPO] = 0.03 M, [MMA] = 10%V/V, [reaction temperature] = 50°C and [reaction time] = 120 min. Methyl iodide was used to measure the contact angle, which revealed the oleophobic nature of grafted PTFE-g-MMA film. Maximum contact angle 95.5° of PTFE-g-MMA film was observed at optimum grafting conditions. The surface morphology of PTFE-g-MMA films was studied by Field emission scanning electron microscopy (FE-SEM) and x-ray diffraction (XRD) analysis confirmed the change in structure of PTFE after MMA grafting. [ABSTRACT FROM AUTHOR]

Hydrophobic and oleophobic surfaces with multi-scale structures were prepared on epoxy coating surfaces by using a facile process with fluorosilicone copolymer and SiO2 nano-particles. The fluorosilicone copolymers were synthesized using perfluoroalkyl acrylate (FA), vinyltriethoxysilane (VTES) and styrene (St) as comonomers via radical emulsion polymerization. In this paper, the surface properties of epoxy coating modified by fluorosilicone copolymer and SiO2 nano-particles were analyzed by using the contact angle measurement. The results showed that the modified epoxy coating surface exhibited not only excellent hydrophobicity but also oleophobicity, the water contact angle reached as high as 149° and the oil (atoleine) contact angle 101°, respectively. [ABSTRACT FROM PUBLISHER]