Wire enamels

Wire coating Wire, corded Wire covering Wire, electrical Wire enamel Wire insulation Wire materials Wire-rope machines Wires... 

Isophthahc acid is also used in formulations for adhesives, inks (qv), wire enamels, and dental materials (qv). Copper isophthalate [10027-31-3] is an ingredient in algicides and fungicides (98). 

Polymers based on trimellitic anhydride are widely used in premium electromagnetic wire enamels requiring high temperature performance. Several types of trimellitic anhydride-derived polymers are used as wire enamels poly(amide—imide)s (133), poly(ester—imide)s (134), and poly(amide—imide— ester)s (135). Excellent performance characteristics are imparted by trimellitic anhydride-based polymers for wire enamel requirements of flexibiUty, snap, burnout, scrap resistance, heat shock, and dielectric strength. 

Du Pont produces this polymer under the trade names of Kapton, Pyrafin, Vespel, and Pyre-ML. The trade names refer to polyimides used for film, semiconductor coatings, mol ding applications, and wire enamel, respectively. They have exceUent thermal, electrical, and physical properties. 

This includes wire enamels on a base of polyvinyl formal, polyurethane or epoxy resins as well as moulding powder plastics on phenol-formaldehyde and similar binders, with cellulose fillers, laminated plastics on paper and cotton cloth base, triacetate cellulose films, films and fibres of polyethylene terephthalate. 

The main application of poly (vinyl formal) is as a wire enamel in conjunction with a phenolic resin. For this purpose, polymers with low hydroxyl (5-6%) and acetate (9.5-13%) content are used. Similar grades are used in structural adhesive (e.g. Redux) which are also used in conjunction with phenolic resin. Poly(vinyl formal) finds some use as a can coating and with wash primers. Injection mouldings have no commercial significance since they have no features justifying their use at current commercial prices. 

The first commercial applications of polypyromellitimides were as wire enamels, as insulating varnishes and for coating glass-cloth (Pyre.ML, Du Pont). In film form (Kapton) many of the outstanding properties of the polymer may be more fully utilised. These include excellent electrical properties, solvent resistance, flame resistance, outstanding abrasion resistance and exceptional heat resistance. After 1000 hours exposure to air at 300°C the polymer retained 90% of its tensile strength. 

Available as wire enamels for some years, they also became available from Bayer as electrical insulating films in 1970. 

Phenolic resins are useful surface coating materials. Resols are useful for stoving lacquers for coating chemical plant, textile equipment, razor blades, brassware cuid food cans. Phenolic resins are used with poly(vinyl formal) as a flexible, tough and solvent-resistant wire enamel. Oil-soluble resins based on synthetic phenols form the basis of some gloss paints. 

Cresylic acid is mainly used as degreasing agent and as a disinfectant of a stabilized emulsion in a soap solution. Cresols are used as flotation agents and as wire enamel solvents. Tricresyl phosphates are produced from a mixture of cresols and phosphorous oxychloride. The esters are plasticizers for vinyl chloride polymers. They are also gasoline additives for reducing carbon deposits in the combustion chamber. 

Voltron (DuPont) is a wire enamel in which nanoparticles of silicates or other inorganic materials are chemically linked to the enamel polymer backbone. Voltron provides a much better corona resistance than enamels merely filled with inorganic ingredients. One of the first ignition coils to use Voltron is for road-course and circle-track racing of modified stock cars. 

Uses Solvent for liquids, gases, vinyl resins, wire enamels polyacrylic fibers gas carrier catalyst in carboxylation reactions organic synthesis (manufacture of aldehydes, amides, amines, esters, heterocyclics). 

Polyimide films have excellent electrical properties and a tensile modulus of over 400,000 psi at 25°C. Over 60 percent of this modulis is retained at 200°C. Polyimide wire enamels are stable for up to 100 Oiousand hours at 200°C. Polyimide fibers have a tenacity of 7 g/denier at 25°C and over 1000 hrs at 2833C is required to reduce the value to 1 g/denier. 

Spreading (smearing) is the most widely used and well-studied method of plastisot processing for making linoleum, artificial leathers, wire enameling, etc. Descriptions of the process and its quantitative analysis may be found elsewhere3-4 31>. 

Uses 4-Aminophenyl ether is a resin used in the manufacture of a variety of industrial products, (e.g., in insulating varnishes, flame-retardant fibers as wire enamels, coatings, films). It also is used in the manufacture of other industrial fire-resistant products. 

The three-component cyanate/maleimide/epoxide compositions are mainly used as polymer matrix in copper clad laminates and in carbon fiber composites for engineering purposes. High heat resistance, water and solvent resistance, mechanical and impact strength is claimed. A composition for copper wire enamelling [121] and a resin for electric motor coil windings impregnation were described [107]. 

Titanates have been instrumental in the bonding of fluorinated resins to packaging films, poly(hydantoin)—polyester to polyester wire enamel, polysulfide sealant to polyurethane (a phosphated titanate is recommended), polyethylene to cellophane using a titanated polyethylenimine, and silicone mbber sealant to metal or plastic support using polysilane (Si—H) plus polysiloxane (Si—OR) and titanate as the adhesive ingredients (450—454). Polyester film coated first with a titanium alkoxide, then with a poly(vinyl alcohol)—polyethylenimine blend, becomes impermeable to gases (455). 

Sanjana, Z. N. A study of wire enamel cure using dielectric analysis, Proc. IEEE Conf. Electr. and Electronic Insul., 15, 150 (1981)... 

Observed Tg s vary from -123°C for polyfdimelhyl siloxane) (1-43) to 273°C for polyhydantoin (11-2) polymers used as wire enamels and to even higher temperatures for other polymers in which the main chain consists largely of aromatic structures. This range of behavior can be rationalized, and the effects of polymer structure on Tg can be predicted qualitatively. Since the glass-to-rubber transition... 

Methyl- and methylphenyl-resins are utilized as raw materials for paints, binders and in building preservation. In the electrical industry they are utilized as electrically insulating lacquers (wire enamel) and for the bonding of glass filaments or mica insulating materials. Special meltable solid resins are flow aids in the injection molding of porcelain matrices. 

As in case of mixed cresols, mixed xylenols have been used for manufacture of carbolic soaps, disinfectants, wire enamels, and fire-retardant plasticizers. However, 2,4-xylenol, 2,6-xylenol, and 3,5-xylenols have been used for organic chemical synthesis. 2,6-Xylenol is a precursor for an engineering plastic polyphenylene oxide also known as polyphenylene ether. 

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