Glass cloth coating

Equipment for impregnating asbestos is conceptually similar to those used for glass cloth coating. Asbestos readily picks up PTFE dispersions and the amount of uptake depends on the concentration of PTFE in the dip tank. The dispersion may be diluted moderately with deionized water or substantially using a dilute aqueous solution of a nonionic surfactant such as Triton X-100. The speed of the asbestos yam movement through the dip tank has little effect on the amount of uptake. The length and capacity of the oven determines the maximum throughput of the process. 

A glass-cloth coated with FEP exhibited contamination in the form of black spots resembling carbon black. The coating process did not use any carbon black, thus ruling it out as a source of contamination. What was the nature of contamination and its possible sources ... 

Waterproof. Waterproofing barrier systems may be either hot- or cold-appHed. The hot-appHed generaUy involve a bituminous material such as asphalt used in conjunction with a reinforcing fabric such as roofing felt, cotton, or glass cloth. Cold-appHed can be bituminous or elastomeric materials either in Hquid or sheet form, with or without fabric reinforcement. Liquid elastomeric treatments include neoprene, polyurethanes, and blends of these or epoxies with bituminous materials. Among the commonly used precured elastomeric sheet materials are neoprene, polyisobutylene, EPDM mbber, and plasticized PVC. Polyethylene and PVC films and nonwoven plastic or glass fabric coated with bituminous materials also find use (78). Because these... 

Figure 5-30. Expander during hot mechanical running test in Jeannette, Pennsylvania facility. Four inches (102 mm) of insulation is secured to the casing with refractory-type anchors welded to the casing. Final site treatment includes a layer of 1.1 Ib/fF (5 kg/m ) lead foil for acoustic purposes and two outer coats of open-weave glass cloth and emulsion reinforcement, for an aluminum gray color.

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. 

The thermosetting materials are said to be initially linear but are cross-linked by heating in air to a temperature of at least 345°C. It is claimed that they have a useful working range up to 315°C. The materials may be used in compression mouldings powders, as the binder resin in glass cloth laminates and as the polymer base in heat-resistant metal coatings. 

Glass-cloth-reinforced laminates, silane performance in, 22 702 Glass coatings, thin-film, 12 608—609 Glass components, 12 595t Glass compositions, 12 594t 13 387 bioactive, 12 611... 

Glass cloth - [ELECTRONICS, COATINGS] (Vol 9) -mica bound to [MICA] (Vol 16)... 

Laminate manufacture involves impregnation of glass cloths with a liquid resin in a dip coating operation. The treated glass cloths are dried in an oven and the resin pre-cured. Even if most of the products are applied as aqueous solutions of the prepolymers, powdered materials are also available. The advantage of the powdered products is their better chemical stability compared to the aqueous solutions. The resin content of the final products lies between 30 and 70%. 

Polyester coatings are suitable for concrete and steel substrates. The systems are generally used as laminates in conjunction with the use of glass cloth or glass flakes as the reinforcement. Polyester coatings are particularly useful in areas where resistance to mineral acids is required. Typical properties of polyester coatings are given in Table 9.2. 

One can think of the PTFE dispersion coating process as impregnation of fibrous or porous materials such as glass fiber, woven glass cloth, and polyaramide fibers and fabrics. The composite product combines the properties of PTFE and substrate. The polytetrafluoroethylene coated or impregnated products are characterized by a number of common attributes, Table 5.9. 

Coated woven glass cloth and fiber Architectural fabrics, gaskets and laminates, electrical insulation, release sheets, hoses... 

Coated woven glass cloth Filtration cloth Packings... 

Excessive coatings may be wiped from the glass cloth by applicators. They include, in the order of decreasing effectiveness, sharp-edged knives (doctor blade), round-edged knives, wire-wound rods, and fixed gap horizontal metering rolls. Coating thick-... 

A primer adhesive is first applied to a properly prepared concrete surface. A thin coat of epoxy mortar is then applied with a trowel. While this thin coat is still wet, a fiberglass membrane is rolled into the mortar. The edges of the membrane should be overlapped 2 inches. The mortar will squeeze up through the voids in the fiberglass mesh, resulting in adhesive base to which the final epoxy mortar will adhere. While this first application of mortar is still tacky, the second layer of epoxy mortar is applied over the glass cloth. This second layer may then be screeded and leveled. ... 

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