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Superhydrophobic and superoleophilic glass-fiber fabric with high water-in-oil emulsion separation efficiency was prepared by a simple sol-gel process using MTES (triethoxymethylsilane) as precursor. The surface chemical composition, micromorphology, pore size distribution, thermal stability, and the wetting behavior of the glass-fiber fabric were characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, capillary flow porometry, thermogravimetric analysis, and water (pH ¼ 1-14)/oil contact angle measurement. The contact angle of the treated fabric at different temperatures was tested in a muffle furnace. The results show that the micromorphology of the glass-fiber fabric almost remains the same after MTES treatment, while the pore size of the treated glass-fiber fabric decreases slightly. Hydrophobic -CH 3 groups are grafted onto the fiber surface and MTES copolymers are formed on the junction of fibers of the glass-fiber fabric. The treated glass-fiber fabric shows superhydrophobicity and superoleophilicity and its separation efficiency for emulsified water in the oil can reach 96.80 wt %. Besides, the treated glass-fiber fabric can withstand acid/alkaline, high temperature environments and maintain high separation efficiency after multiple cycle uses.

Purpose The flammability of poly-acrylate (PA) resin is a major disadvantage in applications that require flame resistance. It has been reported that a flame-retardant PA resin could be prepared by covalent incorporate phosphorous containing monomer with vinyl group via free radical polymerization, and the prepared modified PA resin is expected to exhibit better flame resistance than those by an additive approach. However, the phosphorus-containing monomers reported previously are made from expensive or toxic materials, and the production procedure is tedious and under harsh reaction conditions, which are not feasible for industrial application. Therefore, the purpose of this paper is the preparation of flame-retardant PA resin modified by epoxy resin phosphorous acid (EPPA) and the study of its flame retardancy. Design/methodology/approach EPPA is first prepared by epoxy resin E-51 and phosphorous acid and then used to prepare phosphorous containing PA resin by free radical polymerization. The flame retardancy of the prepared EPPA-modified PA (EPPA-PA) resin is studied. Findings The results show that EPPA can graft onto the PA polymer chain by free radical polymerization, the flame retardancy of the EPPA-PA resin increases as the EPPA content increasing. The flame retardancy of EPPA-PA resin prepared reaches 27.8% and can pass the V-0 rating in the UL-94 test when EPPA content is 30.0%. SEM and EDS results indicate that phosphorous element in the EPPA-PA resin shows a condensed-phase flame retardant effect. Research limitations/implications The grafting degree of EPPA cannot be accurately tested. Practical implications It is expected that the large-scale production of this epoxy resin phosphoric acid modified PA resin will enable practical industrial applications. Originality/value This method for synthesis of epoxy resin phosphoric acid modified PA resin is newfrangled.

Purpose The flammability of epoxy resin is a major disadvantage in applications that require flame resistance. Epoxy monomers and hardeners containing flame-retardant elements are molecularly incorporated in the resin network are expected to exhibit better flame resistance than those borne on an additive approach. In recent years, because of health and environmental regulation, the use of waterborne coatings has received many attentions. However, waterborne epoxy resin curing agent with excellent flame retardancy has been seldom reported. The paper aims to study the preparation of waterborne P-N-containing epoxy resin curing agent and its performances (P-N – phosphorous and nitrogen). Design/methodology/approach Waterborne P-N-containing epoxy curing agent was prepared in this study using reactive flame retardant 10-(2,5-dihydroxyphenyl)-9,10-dihydro-9-xa-10-phosphaphenanthrene-10-oxide, liquid epoxy resin, triethylenetetramine and butyl glycidyl ether at the mole ratio of 1.0:2.0:2.0:2.0. Findings The results show that the epoxy thermoset from the prepared P-N-containing curing agent presents good flame retardancy and can pass the V-1 rating, and the cured epoxy thermoset film presents excellent performances such as water resistance, adhesion, impact resistance and pencil hardness. This study provides useful suggestions for the application of the water-borne flame retardancy epoxy resins in coating industry. Research limitations/implications Each step of products during the preparation of waterborne P-N-containing epoxy curing agent cannot be accurately tested. Originality/value This method for synthesis of waterborne P-N-containing epoxy curing agent is novel and could be used for various applications in epoxy coating industry.

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