Solvent epoxy resin

Electricians Soldering fluxes, metal cleaners (solvents), epoxy resins, PCBs and PBBs... 

Furfuryl alcohol is shipped in bulk or dmms. Although not corrosive to metals, it is a powerful solvent and penetrant containers, tanks, lines, and valves need to be in good condition to avoid potential leakage. Furfuryl alcohol can be stored in containers lined with baked phenoHc resin coatings however, it should not be put in containers that are coated with lacquers, varnishes, or epoxy resins because it is an excellent solvent for many such coatings. 

TetrabromobisphenolA. TBBPA is the largest volume reactive flame retardant. Its primary use is in epoxy resins (see Epoxyresins) where it is reacted with the bis-glycidyl ether of bisphenol A to produce an epoxy resin having 20—25% bromine. This brominated resin is typically sold as a 80% solution in a solvent. TBBPA is also used in the production of epoxy oligomers which are used as additive flame retardants. 

Uses. Diacetone alcohol is a widely used solvent in the coatings industry where it finds appHcation in hot lacquers which require high boiling components, and in bmshing lacquers where its mild odor, blush resistance, and flow-out properties are desired. Diacetone alcohol is also a solvent for nitrocellulose, cellulose acetate, and epoxy resins. 

Inversion ofMon cjueous Polymers. Many polymers such as polyurethanes, polyesters, polypropylene, epoxy resins (qv), and siHcones that cannot be made via emulsion polymerization are converted into latices. Such polymers are dissolved in solvent and inverted via emulsification, foUowed by solvent stripping (80). SoHd polymers are milled with long-chain fatty acids and diluted in weak alkaH solutions until dispersion occurs (81). Such latices usually have lower polymer concentrations after the solvent has been removed. For commercial uses the latex soHds are increased by techniques such as creaming. 

Isopropa.nola.mines. Reaction of propylene oxide with ammonia yields mono-, di-, and triisopropanolamines. These products find use as soluble oils and solvents, emulsifiers, waterless hand cleaners, cosmetics, cleaners, and detergents. In industrial apphcations isopropanolamines are used in adhesives, agricultural products, corrosion inhibitors, coatings, epoxy resins, metalworking, and others (51). 

Process Raw Material. Industrial solvents are raw materials in some production processes. Eor example, only a small proportion of acetone is used as a solvent, most is used in producing methyl methacrylate and bisphenol A. Alcohols are used in the manufacture of esters and glycol ethers. Diethylenetriamine is also used in the manufacture of curing agents for epoxy resins. Traditionally, chlorinated hydrocarbon solvents have been the starting materials for duorinated hydrocarbon production. 

Owing to relatively low viscosity, these resins offer advantages for 100% soHds (solvent-free) systems. Higher filler levels are possible because of the low viscosity. Faster bubble release is also achieved. Higher epoxy content and functionaHty of bisphenol F epoxy resins can provide improved chemical resistance compared to conventional epoxies. 

To improve the weatherabUity of epoxies, which normally chalk and yeUow, epoxy—polyester aUoys or hybrids are used. These powders with improved overbake resistance cure at temperatures as low as 130°C. They have film flexibiHty similar to epoxy resins, but their hardness is slightly decreased. Corrosion resistance is equivalent to epoxy powders in most cases, although solvent and alkaH resistance is inferior. 

Modified liquid epoxy resins liquid epoxy resins with added reactive diluents or solvents mild to moderate irritants moderate to strong sensitizers low volatility, exposure unlikely unless heated, sprayed, or spread over large unventilated surfaces low toxicity... 

Epoxy resin cements are specifically intended for resistance to caustic alkalis and organic solvents, but they also have fair acid resistance. They have excellent bond strength to other materials including ceramic and concrete. The corrosion resistances of the cements described above are given in Table 3.40. 

Epoxy resin paints, inferior to chlorinated rubber for resistance to strong acids, are excellent for dilute acids and strong alkalis. They produce a harder, more abrasion-resistant coating than does chlorinated rubber and are much better for resistance to fats, oils and many organic solvents. Table 3.50 gives data on the chemical resistance of epoxy resin coatings to different materials. 

In earlier research the alignment operation was applied to CNTs in the form of a CNT-polymer resin [24] or CNT suspended in a solvent [25]. In the method developed by Ajayan et al. [24], purified MWCNTs were dispersed in an epoxy resin which was cut with a diamond knife and a microtome in order to obtain aligned CNTs. De Heer et al. [25] used a 0.2 (im pore ceramic filter in order to create an MWCNT suspension in ethanol, and to obtain a black deposit which was transferred to a plastic surface (Delrin or Teflon) by pressing the filter onto the polymer. However, only a moderate degree of orientation and uniformity in length of the CNTs was achieved by this method. 

Nitropropanes are good solvents for vinyl and epoxy resins. They are also used to manufacture rocket propellants. Nitromethane is a fuel additive for racing cars. 

Major uses of epoxy resins are coatings for appliance finishes, auto primers, adhesive, and in coatings for cans and drums. Interior coatings of drums used for chemicals and solvents manifests its chemical resistance. 

For resistance to acid conditions alone, traditional filled and unfilled bituminous solutions (which have economic advantages), chlorinated rubber and shellac have been used. Crosslinking coatings, e.g. amine-cured epoxy resins, often blended with coal-tar which develops resistance to oils and solvents, have obvious advantages on chemical plant. 

The epoxy-acrylic resin referred to above is a graft copolymer prepared by the polymerisation of acrylic monomers in the presence of the epoxy resin in such a way that grafting of the acrylic onto the epoxy takes place. Water dispersibility is achieved by neutralising carboxyl groups in the acrylic polymer chain with ammonia or amine. Amino or phenolic resins are used as crosslinkers. Alternatively, solvent-borne epoxy-amino or epoxy-phenolic lacquers can be used. 

Diglycidyl ether of bisphenol A (DGEBA, MW 340 Da) and 4,4 -dihydroxy-diphenylmethane (DHDPM, MW 200 Da) were analysed by SEC-MALS [784]. DGEBA and DHDPM are the basic oligomers of epoxy resins and phenol-formaldehyde condensates, respectively, which are widely used in the electronic and automotive industries. Excellent reproducibility ( 1 %) and good accuracy (better than 10%) were observed. SEC has also been used for the determination of mineral oil in extended elastomers [785] and in PS [178]. With heptane containing 0.05% isopropanol as the mobile phase, mineral oil is completely unretained and elutes before the solvent via SEC all other components in a PS extract are retained on silica and elute after the solvent peak. 

Fine chemicals These are produced in small volumes and purchased on the basis of chemical composition, purity and price. Examples are chloropropylene oxide (used for the manufacture of epoxy resins, ion-exchange resins and other products), dimethyl formamide (used, for example, as a solvent, reaction medium and intermediate in the manufacture of pharmaceuticals), n-butyric acid (used in beverages, flavorings, fragrances and other products) and barium titanate powder (used for the manufacture of electronic capacitors). 

Fig. 3.4f shows an exclusion chromatogram on unmodified silica. The sample is an epoxy resin with an average Mr of 900. Fig. 3.4g shows the determination of pesticide residues in a sample of chicken fat, and is an example of how exclusion can be used to clean up complex samples. First, a pesticide-free sample of the fat is run as a blank, then the blank is spiked with the pesticides to determine their retention volumes. When the sample is injected, the eluent containing the pesticides is collected. The solvent is evaporated, the residue dissolved in acetonitrile and the pesticides are then separated on a reverse phase column. 

Carbon disulphide was used as an extraction solvent when analysing epoxy resins. On one occasion, adding to a hardener produced a vigorous fume-ofif leaving a residue looking like sulfur [1], Amines and complexes thereof are used as hardeners, and the reaction with, especially, polyamines to give dithiocarbamates is surprisingly exothermic [2],... 

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