Coatings, antifoams

Antibubble DF-162 antifoam, clear lacquers Drewfax S-600 antifoam, coatings... 

HAp coatings, 14 105 HapMap project, 20 839 Hapten-antibody interactions, 9 64 Haptic sensor, for skin conditions, 3 749 Harcros antifoam, commercial defoamer, 3 24 It... 

Foamed emulsions are disperse systems with two disperse phases (gas and liquid) in the disperse medium (surfactant solution). Water foamed emulsions are formed when foams or aqueous surfactant solutions are used to clean up oil deteriorated surfaces, in the process of oil flotation of waste waters, in firefighting when the foam contacts various organic liquids and in the processes of chemical defoaming (foam destruction by antifoams). Individual foamed emulsions can have practical importance e.g. a foamed emulsion of bitumen is used in road coating foamed emulsions from liquid fuels are used as explosives. 

Use Wiredrawing lubricant, antifoaming agent, coupling agent in resin coatings, chemical intermediate. 

Use Hydraulic fluids, rubber lubricants, antifoam agents, intermediates in urethane foams, adhesives, coatings, elastomers, plasticizers, paint formulations, laboratory reagent. 

Antifoam. [Harctos] Silicone blend de-foamer for industrial processing, carpet cleaning, wood pulping, paper coating, textile mfg. 

Hydrophobic Silicas. Because foaming is a surface phenomenon, any antifoam used must concentrate at the surface (or gas—liquid interface). Hydrophobic silicas, which are silicas that have been treated with a compound that causes them to float on the top of water, have been used to fulfill this function for almost 30 years. U.S. Patent 3 408 306 (5) discloses the use of a hydrophobic silica dispersed in a hydrocarbon oil. Hydrophobic silica for this composition, which is still in use today, is made either by continuous ( dry roast ) or batch process. In either process, precipitated silicas rather than silica gels or fumed silicas are typically used to make antifoams. During a continuous process, silicone oils, usually poly(dimethylsiloxane), are sprayed onto a bed of hydrophilic silica. The bed is heated to temperatures ranging up to 300 °C, and reaction times are up to 20 h. At these temperatures and reaction times, bond formation between the silica particle and silicone oil may occur in addition to simple coating of the particle. 

The defoaming of blood is usually accomplished with the aid of silicone-coated mesh. Dimethylpolysiloxane-based antifoams can be used to coat Teflon or steel or polypropylene mesh. A settling chamber is used separately or as part of the defoaming chamber to allow all residual bubbles to escape. 

Particle bounce can be effectively controlled by coating an adhesives layer on the collection surface to keep collected particles from bouncing off the plates. Typical coating materials include Antifoam A, Hi-Vac silicone grease, Apiezon L, viscous oils, Vaseline, and glycerin. The typical thickness of the adhesive... 

Sierra Radial Slit Jet Shim stock coated with Dow Antifoam A 5.2... 

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