Flake glass coating

Pigments used in barrier coatings should also be hydrophobic in nature, and possess good adhesion across pigment-binder interfaces. Some typical pigments used are flat platey aluminum flakes, glass flakes, stailness steel flakes and micaceous iron oxide. 

Uses Vinyl esfer for hand lay-up, spray-up, and filamenf winding, flake glass, filled lining and coating compds. fo confacf crosslink polyester resins... 

An unacceierated, low viscosity, highly cross-linked novolac epoxy vinyl ester offering superior oxidation resistance, excellent solvent and acid resistance and suitable for hand-lay, spray/projection lamination and for flake glass, filled linings and coating compounds. Hetron 980 and 980/35 are recommended when increased toughness is required at less critical operating temperatures.)... 

It has long been known that it is possible to modify the electrical properties of polymers by means of conductive admixtures of many kinds or, rather, to make them conductive. Despite this, electrically conductive polymers are still not of any great economic importance as materials. They do, however, play an indispensable role in many specialized technical applications. They are mostly manufactured by incorporating electrically conductive carbon black or carbon fibers in a variety of polymers, especially thermoplastic polymers. Other conductive additives, such as steel fibers, aluminum flakes, metal-coated carbon fibers, metal-coated hollow glass spheres, and low melting metallic alloys have not so far played any decisive part in the development of electrically conductive polymers. 

Unsaturated polyesters The formation of the coating occurs in situ by the reaction between polyester resin and styrene, activated by a catalyst such as organic peroxide. The main use as coatings is in the formation of glass fiber or glass flake, reinforced plastics. 

The Engelhard product based on calcium borosilicate glass flakes is said to give a star-like glitter to coatings. 

It is also possible to formulate epoxy coatings by using glass flakes. This improves the abrasion resistance. Such coatings can be applied at a dft of between 1500 xm and 3000 xm (International Paints, 1996). 

It is impossible to achieve a dft between 400-500 xm in two coats without fibre glass reinforcement. In some laminate systems, glass flakes are also used as fillers. Their function is to minimise the shrinkage stress. 

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. 

Chemical composition variable composition silver coatings in Conduct-O-Fil solid glass spheres and fibers -4-16 wt%, 30% on hollow glass spheres, 65 wt% on mica flakes, 8-19 wt% on copper flakes, 24 wt% on nickel granules, 20 wt% on aluminum particles, nickel coating on Compmat carbon fiber is 24 wt%... 

Dry bulk resistivity, O-cm 0.005-0.008 (silver-coated products of PQ), 0.0017 (silver coated solid and hollow glass spheres - Conduct-O-Fil), 0.004 (silver coated glass fiber - Conduct-O-Fil), 0.0005-0.0006 (silver coated copper powder - Conduct-O-Fil), 0.0012 (silver coated copper flake - Conduct-O-Fil), 0.0007 (silver coated aluminum sphere - Conduct-O-Fil), 0.003 (silver coated inorganic flake - Conduct-O-Fil), 0.006 (silver coated nickel granules - Conduct -O-Fil), 0.0000016 - pure silver... 

Particle size, pm 3 (AgCLAD silver-coated, thick-wall spheres), 45-125 (Metalite, silver-coated, fight glass spheres), 50 to 300 mm (Bekinox VS for conductive textiles) Conduct-O-Fil glass spheres - 12-92, copper flakes - 10-150... 

Conduct-O-Fil S series - silver coated solid glass spheres. Twelve grades in particle sizes range of 12-92 pm. Materials for conductive adhesives, caulks, coatings, elastomers, greases, inks Conduct-O-Fil SH - silver coated hollow borosilicate glass spheres containing 30 wt% silver Conduct-O-Fil SM - silver coated mica flake... 

Figure 2.39. SEM micrographs of silver-coated flakes and spheres. Upper left - Novamet silver coated nickel flakes, upper right - Conduct-O-Fil SC230F8, silver coated copper flakes, bottom - Conduct-O-Fil solid glass spheres coated with silver, left - spheres at lOOx magnification, right - spheres in silicon resin. Courtesy of Novamet Specialty Product Corporation, Wyckoff NJ, USA and Potters Industries, Inc., Valley Forge, PA, USA.

Typical fillers glass fiber, carbon fiber, aramid, antimony trioxide, zinc borate, stainless steel fiber, graphite, nickel coated graphite, aluminum flakes, metallized glass... 

Typical fillers calcium carbonate, glass fiber, carbon fiber, zinc borate, PTFE, aluminum flake, graphite fiber, nickel coated graphite fiber... 

Since the HEPA filters are particulate filters and will pass acid vapors, the danger of airborne metallic contamination resulting from the flaking of corroded metallic objects could exist. Thus, stainless steel fixtures were used and were coated with a Teflon spray. Other metal surfaces were covered with a protective vinyl paint. A glass-windowed exit-only emergency door was provided for safety. 

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