Silicone emulsion

Dispersible silicone emulsions are generally preferred for aqueous systems, whereas silicone fluids and compounds are preferred for non-aqueous systems. Silicones are widely employed in cooling water treatment programs, less so in boiler plants because of higher operating costs than available alternatives, but also because of sometimes questionable emulsion stability at higher temperatures. 

Where employed for BW applications, silicone emulsion strengths, emulsion stability, spreading coefficients, and effectiveness rates may vary considerably and the preferred product should be identified by comparative evaluation. 

Any substance used to prevent rubber sticking to itself or to the surface of a mould. The lubricant may be a dry powder such as soapstone or a liquid such as silicone emulsion. See Dusting Agent and Mould Release Agent. 

Many rubber compounds have a tendency to stick in the mould cavity after vulcanisation and require some type of mould release agent. The substances used are surface-active materials such as detergents, soaps, wetting agents, silicone emulsions, aqueous dispersions of talc, mica and fatty acids, applied by spray or brush. Alternatively, dry types based on polytetrafluoroethylene or polyethylene, usually carried in a solvent, can be aerosol applied. An alternative is the addition of an incompatible material to the rubber compound which will bleed to the rubber surface during vulcanisation. 

Mix 10 parts of this dispersion with the silicone emulsion and 82.3 parts of water. 

Fig. 37. Production diagram of antifoaming silicone emulsion 1 - reactor agitator 2, 3 - batch boxes 4 - reactor emulsifier 5 - hydrodynamic changer 6 -pump 7- collector...

Preparation of the antifoaming silicone emulsion. Antifoaming silicone emulsion (OS-2) is a 30% aqueous emulsion of oligomethylsiloxane liquid (the viscosity is below 500 mm2/s) stabilised with the diethyleneglycol ether of higher fatty alcohols CM—Cis. 

Antifoaming silicone emulsion is a homogeneous liquid with colour ranging from white to light brown it is nonflammable and nontoxic. It... 

Preparation of the separating silicone emulsion. Separating silicone emulsion is a 70% aqueous emulsion of oligomethylsiloxane liquid (with a viscosity below 400 mm2/s), emulsified with OP-7 or OP-10. 

The separating silicone emulsion is a homogeneous white liquid. It... 

Silicone emulsion is used in foundry work as a separating agent for manufacturing rods based on furane resins at hot mounting. 

The use of silicone emulsions for detaching rubber articles from pressure molds greatly increases the productivity of pressing, reduces spoilage (by 90%) and costs of cleaning the pressure molds (by 80%). If plastic masses are pressed, the introduction of 1-2% of silicone liquid into the composition helps to detach the article from the mold easily, improves its surface and, besides, keeps the pressure mold in use without cleaning for 4 months. When gypsum molds for ceramic articles are manufactured, lubri-... 

Gee, R.P. (1986) Method of preparing silicone emulsions having small particle size. U.S. 4620878. (Dow Corning Corp. U.S.A). 

Gum, M.L. (1985) Water-in-volatile silicone emulsifier concentrates for mixing with water to form water-in-volatile silicone emulsions that are useful in personal-care formulations and methods of making same. PCT Int. Appl. 8503641. (Union Carbide Corp., USA Application WO). WO. p. 56 pp. 

LE-9300 Silicone Emulsion, Technical Bulletin F-43607A, Textile and... 

The particles of cyclodextrin-grafted silicone are also the vehicles for the transport of the active substance to the site of its therapeutic action. In the case of anti-fnngal dosage form for topical administration action, penetration and slow release in the skin is searched for [21-23]. The stratum corneum top layer is made of cor-neocytes separated by a lipidic intercellular medium. Internal layers, epidermis and dermis are essentially aqueous media. The top layer is hydrophobic whereas the internal layers are hydrophilic. The penetration into the skin is controlled by the hydrophobic character of the particles. Hydrophobic materials easily penetrate and possibly accumulate in the stratum corneum. A slow release of the drug into the deep hydrophilic layers is possible from this medium. Silicone emulsions are often selected for cosmetic formulations because of the favorable spreading of silicone oils at the skin surface together with their low-irritancy properties. 

Fig. 5 Microscopy pictures of giiseofulvin crystals precipitated in water and out from a silicone emulsion. Top Giiseofulvin crystals precipitated by the spontaneous emulsification method 10 mg giiseofulvin in 2.5 mL acetone poured into 5 mL of 0.1 % Polysorbate 20 aqueous solution (left x 20, bar=200pm right xlOO, bar=20pm). Bottom lOmg silicone oil and 64mg giiseofulvin in 2.5 mL acetone poured into 5 mL of 0.1 % Polysorbate 20 aqueous solution (x 20, bar=200 pm)...

Type Viscous silicone emulsion Color White pH 4-5... 

This product is a compounded silicone fluid defoamer it contains 100% active matter. It is thin, translucent and syrupy. Suitable diluents are aliphatic, aromatic and chlorinated solvents. In Itself, it is not water soluble but may be used as a base to make very effective silicone emulsion defoamers to be used in the water phase. 

CNC Antifoam SS is used in the compounding of silicone emulsions as defoamers to be used in the water phase. 

CNC QUICK SET SIL Is used with CNC ARIDRY SN fabric finishes to facilitate curing. Use one part of catalyst to eight (8) parts of CNC ARIDRY SN as received. The catalyst must be diluted with water and added to the diluted silicone emulsion for best bath stability. 

Chemical nature modified silicone emulsion Density 8.2 lbs./gal. 

Chemical nature non-ionic silicone emulsion Appearance white, free-flowing liquid pH 7.5... 

Chemical nature modified silicone emulsion Appearance ivory-colored, pourable liquid Density 8.2 lbs. per gallon... 

ARIDRY SN-25 is a fine silicone emulsion which produces highly durable water repellency on treated fabrics. ARIFIX SN is the catalyst recommended for use with ARIDRY SN-25. These products can be run alone or in conjunction with thermosetting resins, cationic dye fixtures and most all of the organic and inorganic accelerators. Some of the waxy type softeners are compatible with a resin-silicone mix, but each must be checked carefully to be sure that it does not cause back-wetting. 

DANSIL 24 is a reactive softener for durable press fabric treatment. It is a stable, water dilutable silicone emulsion. Its principal use is as a softener with durable press resins. It Imparts increased wrinkle recovery, improved flex abrasion resistance and a soft lively hand to fabrics so treated. 

Type Silicone emulsion silicone polymer system Products DOW CORNING 1111 Emulsion now CORNING T4-0149 crosslinker DOW CORNING 1R2A or 164 catalyst Physical Form Water dilutable liquids... 

Special Properties Silicone emulsion can be used alone in pad operations or as a top softener emulsion system with separate emulsion and crosslinker allows varying hand and other properties by changing the mixing ratios. 

Primary Uses Silicone emulsion for synthetic knits in a pad operation or as a top softener emulsion polymer system for durable-press woven fabrics to improve hand and other characteristics. 

When used on polyester/cellulosic fabrics in conjunction with durable press resins, the silicone emulsion polymer system ... 

Type Silicone emulsion polymer system Products DOW CORNING 1111 Emulsion... 

Special Properties Modification of hand and other physical properties can be varied as needed by changing the ratio of silicone emulsion to the separate crosslinker... 

DOW CORNING 75 emulsion is a reactive, methyl silicone emulsion especially designed for use as a water repellent for all types of fabrics. When used with a catalyst, it provides water repellency used alone it functions as a fabric softener. 

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