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Non-Isocyanate-Based Waterborne Polyurethanes
Published in Ram K. Gupta, Ajay Kumar Mishra, Eco-Friendly Waterborne Polyurethanes, 2022
Ma et al. [32] described stable WNIPU dispersions obtained by the polycondensation of dicarbamate (i.e. isophorone dimethylcarbamate), selected diamines (i.e. 4,7,10-trioxa-1,13-tridecanediamine, poly(propylene glycol) bis(2-aminopropyl ether) with an average Mn of 400 Da, poly(tetrahydrofuran) bis(3-aminopropyl) with an average Mn of 1100 Da), and 3,3′-diamino-N-methyldipropylamine as internal dispersing agent. The resulting coatings were characterized by good impact and solvent resistance. In another work of Ma et al. [33], t-butyl-oxycarbonylated diamines were investigated as dicarbamate monomers for the synthesis of non-isocyanate polyureas or polyurethane-ureas by polycondensation method (diamine/dicarbamate polymerizations). The high molecular weight polymers were prepared from stoichiometric polymerizations of diamines or diols with N-N′-di-t-butyloxycarbonyl isophorone diamine using potassium t-butoxide as a catalyst. Stable dispersions are obtained from NIPUs with 3,3′-diamino-N-methyldipropylamine as internal dispersing agent. The resulting polyurea-based coatings were characterized by higher mechanical properties and solvent resistance compared to the polyurethane-urea coatings synthesized from diols and mentioned earlier carbamate and internal dispersing agent.
Evaluation of Nanostructured Polymeric Coatings for Steel Corrosion Protection
Published in Matthew Laudon, Bart Romanowicz, 2007 Cleantech Conference and Trade Show Cleantech 2007, 2019
A. Aglan, A. Ludwick, M. Reeves
The polymer resins used were an epoxy; Valspar Dura Build TM High Build Epoxy Finish comprised of resin A and hardener B in a 2:1 volumetric ratio. Resin A is a alkyd glycidyl ether and hardener B is isophorone diamine. Union Carbide’s VYHH, which is a vinyl chloride/vinyl acetate copolymer, was also used. Multiwalled carbon nanotubes supplied by Ahwahnee Technology (Dia: 2–15 nm, Length: 1–10 μm, Layers: 5–20) were used as reinforcement in some systems. The VYHH and epoxy coatings were formulated with and without nanoreinforcements via sonication and asymmetric mixing techniques to achieve uniform dispersion. The coatings were applied to steel substrates (25mm X 101.6mm X 1.25mm). The steel substrates were prepared for coating by polishing and rinsing with acetone. Dried substrates were then dipped in the coatings with care taken to ensure an even coat with few defects. After 3 days of hang drying, samples were submerged in a 5% NaCl solution.
Polymer Nanocomposite Coatings: Effect of Crosslinkers and Fillers on the Microstructure and Gas Permeation
Published in Vikas Mittal, Polymer Nanocomposite Coatings, 2016
Organically modified montmorillonites with trade names Nanofil 804, Nanofil 32, Nanofil 15, Cloisite 30B, Cloisite 20A, and Cloisite 93A were supplied by Southern Clay Products (Gonzales, TX). The CEC of Nanofil and Cloisite substrates was earlier measured to be 680 and 880 ueq/g respectively [21]. The epoxy resin, bisphenol A diglycidyl ether (4,4’-isopropylidenediphenol diglycidyl ether) with an epoxide equivalent weight 172–176, was supplied by Sigma (Buchs, Switzerland). Tetraeth-ylenepentamine (TEPA), isophorone diamine (ID), ethylene dioxydiethyl amine (EDDA), tetrahydrofuran (THF), and dimethylformamide (DMF) were procured from Fluka (Buchs, Switzerland). Polypropylene (PP; 100 μm thick) foils to support the nanocomposite films were supplied by Alcan Packaging (Neuhausen, Switzerland). A surfactant (trade name BYK-307) was used to achieve better wetting and adherence of the neat epoxy coating to the substrate foils and was obtained from Christ Chemie (Reinach, Switzerland)
The use of fibre reinforced polymer composites for construction of structural supercapacitors: a review
Published in Advanced Composite Materials, 2023
Jayani Anurangi, Madhubhashitha Herath, Dona T.L. Galhena, Jayantha Epaarachchi
Nowadays, some researchers have used the prepreg filming process to fabricate SSCs [38,43]. The prepreg method, which is easily scaled up in industry, is increasingly popular among the research community as the way of realising high-performance SSCs. As discussed in Section 2.3, Qi and his team suggested the resin filming process to fabricate the structural supercapacitor via the sandwiching of two CAG loaded carbon fibre partial prepregs with the separator prepreg [43]. Ionic liquid-based structural electrolyte which contains bisphenol A diglycidyl ether (BADGE) epoxy, isophorone diamine (IPDA) hardener, and ionic liquid (EMIMTFSI) was applied onto the inner face of the CAG–carbon fibre electrodes to form carbon fibre partial prepregs. An adjustable height film applicator was used to make the structural electrolyte films with the required thicknesses. The prepreg stack of carbon fibre/separator/carbon fibre was laid up for the curing process after copper adhesive strips were attached to the outer faces of the CAG–carbon fibre electrodes. In this way, the weight fraction of the structural electrolyte can be properly controlled, although minor differences can be observed between replicates. Therefore, nominally identical devices can be manufactured by this method, ensuring the repeatability of device fabrication.
Curing processes of binary epoxy-amine systems for manufacturing epoxy-silica films
Published in Materials and Manufacturing Processes, 2020
Elham Naeemikhah, Aziz Ahmadi Khaneghah, Zeinab Shamsi-Jamkhaneh, Hossein Behniafar
Two epoxy resins including bisphenol A diglycidyl ether (BADGE) and polyoxybutylene diglycidyl ether (POBDGE) were considered for curing processes. Isophorone diamine (IPDA) and polyoxybutylene diamine (POBDA) were used as the curing agents of the resins. Two of these four monomers, i.e., POBDGE and POBDA, were based on polyoxybutylene flexible units, and both were synthesized from polytetramethylene glycol (PTMG). The one-step synthesis reaction of POBDGE resin from PTMG and epichlorohydrin (ECH) is shown in Scheme 1(a). POBDA hardener was synthesized via a three-step reaction with PTMG starting material according to our previous report.[40] The structures of the used hardeners are illustrated in Scheme 1(b). Trace amounts of oligomerization arisen from the ring opening of the epoxide rings may also occur alongside the substitution reaction. These polyaddition reactions can lead to an inaccuracy in the measurement of the stoichiometric ratios of the monomers. To minimize the oligomerization phenomenon during the synthesis of POBDGE resin, a large excess amount of ECH was used. In this condition, “m” value was found to be lower than 0.1. Two other monomers, BADGE epoxy resin and IPDA curing agent, were among the most popular monomers, which have been widely used for preparing epoxy materials.
Effects of waterborne epoxy resin on the mechanical properties and microstructure of oil-well cement
Published in Journal of Dispersion Science and Technology, 2022
The waterborne epoxy resin (WEP) and its curing agent are made in the laboratory. Waterborne epoxy resin made use of bisphenol A type epoxy resin E-44 as graft matrix, acrylic acid, butyl acrylate, methyl methacrylate as grafting monomer, propylene glycol methyl ether as reaction solvent. The epoxy resin was grafted acrylic ester with the method of solution polymerization meanwhile epoxy resin molecule chain was introduced hydrophilic group, epoxy resin was given the hydrophilic group as a result that anionic waterborne epoxy resin emulsion was prepared. The curing agent is made by mixing hexamethylene diamine and isophorone diamine in a certain proportion. And their basic performance parameters are shown in Table 4.