Silicone defoaming agent

Silicone Defoaming Agent A few drops of the silicone-defoaming agent sometimes help in breaking an emulsion, and... 

Is a nonionic silicone defoaming agent designed for "quick knock down" of foam for plant processing. The ester dispersion gives moderate viscosity and good stability and ease of solution. 

Is a newly developed non-silicone defoaming agent designed for use in jet dyeing operations to give effective anti-foaming properties, and show immediate knock-down of foam. 

Enzyme Deposition. Glucose oxidase (type X-S), bovine albumin (fraction V), and glutaraldehyde were obtained from Sigma Chemical Company and used as supplied. A silicone defoaming agent (B emulsion) was from Dow Corning. A nonionic surfactant (Tergitol NP-10) from Union Carbide Corporation was also incorporated. 

Defoaming agents are in three principal categories, but sometimes are used in combination II) surfactants made soluble. (2) dispersions of hard panicles, and f3) dispersions of soft panicles. The fatty acid-fatty alcohol combination in hydrocarbon oil is an example of a solubilized surfactant defoaming formulation Paraffinic waxes and laity amides may be used in soft-particle formulations. The most common of the hard-particle formulations is silica or a mineral coated with silicone dispersed in a vehicle. A particle size as small as 0.1X2 micrometer may be optimal. 

A 100% active siicone antifoam compound. May be emulsified to prepare stable silicone defoaming and antifoaming agents for all applications. 

Their low surface tension results in their utilization in the paint industry as flow, gloss and finish improvers. Silicone oil additives enable effect paints to be formulated such as moire effect paints. Their surface and interfacial activity enables their use as defoaming agents and as foam stabilizers for poly(urethane) foams. 

Pure silicone oils are used as defoaming agents in the crude oil industry. In the rubber and plastics industry they are widely used as mold release agents. Their physiological inertness enables their use in cosmetics and pharmaceuticals. Their water repelling (hydrophobic) properties result in skin creams with good protective properties. The hydrophobic properties of silicone oils endow car, furniture and protective polishes with protective and non-aggressive properties. 

Foam can be controlled by chemical, thermal and mechanical means. Chemical defoaming agents (generally extremely surface active substances of limited solubility, e.g. silicones) are best, if they do not impair the quality of the product. 

Silicones and related blends of silicones and other materials are among the most popular types of air release agents in use in liquid resin compounding. A typical base for defoaming is alcohol/silicone. However, one must be careful when using silicone defoamers. The presence of the silicone could cause a surface on the part that will not be amenable to coatings or adhesives. 

Silicone antifoam agents, when used in excess, cause foaming. A squirt of silicone defoamer will temporarily stop foaming too much will make the problem worse. 

Carry-over due to foaming can be controlled by injecting a small amount of silicone antifoam agent. There are a variety of such chemicals on the market and a specific one, effective for many services, can usually be found. However, for most refinery applications, continuous use of antifoam chemicals would be prohibitively expensive. Also the additive may have negative effects on certain down-stream processes. If the wrong defoaming chemical is used, foam formulation can be enhanced. This happened on a distillate fuel desulfurizer when a silicone defoamer, normally used to control foams in a coking unit, was tried. When the correct defoamer is used, concentrations of as little as 1 ppm are effective. 

Many interesting applications of silicones exploit their unusual surface activity. Mixtures of silicones and silica are used as defoaming agents [48] MQ [5]... 

Silicone oils are also used as defoaming agents and have been fotmd to be extremely effective materials. However, the silicone oils suffer from a major drawback in that they tend to remain on the surface of the parts being cleaned, which can adversely affect post-process operations such as painting, plating, welding, or bonding (31). 

Silicone oil as defoaming agent 13, 116 15, 122 Silicon-iron s. Iron-silicon... 

Many of the properties imparted by the additives are interdependent, e.g. the addition of a silicone defoamer will often require a flow agent to counteract cissing. The balance of these minor ingredients is crucial and on many occasions the key to a successful waterborne formulation. Some commonly used ad tives are given in Table 7-10. 

Chem. Descrip. Water-based silicone defoamer Uses Defoamer, leveling agent, wetting agent, mar resist, aid, slip agent in aq. flexographic inks and other coatings... 

Uses Defoamer for silicone antifoaming agent for a wide variety of end uses Lanofoam S-25 [Lenmar]... 

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