Defoaming definition

It has been shown (16) that a stable foam possesses both a high surface dilatational viscosity and elasticity. In principle, defoamers should reduce these properties. Ideally a spread duplex film, one thick enough to have two definite surfaces enclosing a bulk phase, should eliminate dilatational effects because the surface tension of an iasoluble, one-component layer does not depend on its thickness. This effect has been verified (17). SiUcone antifoams reduce both the surface dilatational elasticity and viscosity of cmde oils as iUustrated ia Table 2 (17). The PDMS materials are Dow Coming Ltd. polydimethylsiloxane fluids, SK 3556 is a Th. Goldschmidt Ltd. siUcone oil, and FC 740 is a 3M Co. Ltd. fluorocarbon profoaming surfactant. 

Foam inhibition is evaluated by the following procedure a definite quantity of the antifoam is added (usually - 0.1 cm3) to the foaming solution (100 cm3). Solid and paste-like antifoams are introduced as solutions. The time needed to fill up the foam vessel as well as the average foam lifetime with Tm and xam, respectively, with and without antifoams, are measured. It is convenient to express the foam inhibition ability either as the relative stability Tre[ (Eq. (9.2)) or as the defoaming coefficient [16]... 

The third characteristic, efficiency of defoaming ability, is determined by measuring the foam volume, broken down in unit time. This is done by adding a definite quantity of an antifoam (for example, 0.1 cm3 10% solution) as drops or aerosol. 

The possibility to use Cm as a parameter characterising foam inhibition has been demonstrated for the first time in [60]. It was shown that the increase in the concentration of silicon oil Caf (antifoam) led to increase in Cm- That is why it was proposed to used the ratio Caf/Cm as a quantitative measure of the defoaming ability. However, it should be noted that the silicon oil concentrations at which inhibition of black spot formation was observed, were very low (10 5-10 9 %). For that reason it is difficult to conclude definitely whether the system was a real solution or represented a diluted emulsion of the antifoam in the surfactant solution. 

This chapter provides an introduction to the occurrence, properties, and importance of foams as they relate to the petroleum industry. The fundamental principles of colloid science may be applied in different ways to stabilize or destabilize foams. This application has practical importance because a desirable foam that must be stabilized at one stage of an oil production process, may be undesirable in another stage and necessitate a defoaming strategy. By emphasizing the definition of important terms, the importance of interfacial properties of foam making and stability is demonstrated. 

CAS 64365-17-9 EINECS/ELINCS 264-848-5 Synonyms Pentaerythritol hydrogenated rosinate Definition Ester of pentaerythritol and hydrogenated acids from rosin Uses Tackifierfor adhesives in protective and barrier-type coatings film-former in cosmetics defoamer in food-contact paper/paperboard in food-contact animal glue in wood preservatives for food contact Features Thermoplastic resin... 

Definition Ammonium salt of tall oil acid Uses Surfactant, emulsifier in cosmetics in resinous/polymeric food-contact coatings for polyolefin films in food-contact paper/paperboard food-contact cellophane in resin-bonded filters for food contact Regulatory FDA 21CFR 175.320, 176.170, 176.200, 177.1200, 177.2260 Ammonium tallow sulfate Synonyms Tallow sulfated, ammonium salt Uses Defoamer in food-contact coatings in paper/paperboard in contact with aq./fatty food Regulatory FDA 21CFR 176.170, 176.200... 

Synonyms Alkanes, C8-9-iso- Alkanes, iso-, C8-9 C8-9 isoalkanes Isoalkanes, C8-9 Definition Mixt. of branched chain aliphatic hydrocarbons with 8-9 carbons in alkyl chain Uses Solvent for coatings, cosmetics defoamer in processing foods in coatings on fruits/vegetables/egg shells in froth flotation cleaning of vegetables in insecticides for processed foods... 

Synonyms PEG-8 coconut alcohol PEG 400 coconut ether POE (8) coconut ether Definition PEG ether of coconut alcohol Formula R(OCH2CH2)nOH, R represents coconut radical, avg. n = 8 Properties Nonionic Toxicology TSCA listed Uses Raw material for mfg. of textile, leather, paper auxs., detergents, emulsifiers, cosmetics emulsifier in cosmetics defoamer in food-contact paper/paperboard in food-contact textiles... 

Definition Mixture of fatty alcohols Toxicology TSCA listed Uses Emollient, emulsifier in cosmetics superfatting agent in shampoos raw material for sulfation, ethoxylation defoamer in food-contact paper/paperboard in food-contact textiles... 

Definition Mixt. of fatty acids derived from corn oil Uses Surfactant, emulsifier, emollient in cosmetics in food pkg. adhesives defoamer in food-contact paper coatings, paper/paperboard in surf, lubricants for mfg. food-contact metallic articles Reguiatory FDA 21CFR 175.105, 176.200, 176.210, 178.3910... 

Definition Monoester of glycerin and a blend of palmitic and stearic acids Empirical C63H116O12 Properties Nonionic Uses Emollient, stabilizer, emulsifier, dispersant for cosmetics food emulsifier starch complexer excipient in tablets lubricant, and binder in pharmaceuticals suspending agent thickener defoamer in... 

Definition End prod, of controlled hydrogenation of a mixture of mono, di and triglycerides derived from soybean oil Properties Nonionic Uses Emollient, emulsifier, stabilizer, dispersant, opacifier for cosmetics, foods, and pharmaceuticals defoamer in food-contact paper/paperboard in food-contact textiles Regulatory FDA 21CFR 176.210, 177.2800 Trade Name Synonyms Monomuls 60-45 t[Griinau GmbU http //www.gruenau-illertissen. de/com/index. html]... 

Synonyms Coconut fatty acids, magnesium salts Fatty acids, coco, magnesium salt Fatty acids, coconut oil, magnesium salt Definition Magnesium salt of coconut acid Uses Emulsifier, surfactant in cosmetics in food-pkg. adhesives, food-contact resinous/polymeric coatings for polyolefin films, paper/paperboard in contact with aq./fatty foods, food-contact cellophane defoamer in food-contact coatings/paper surf, lubricant in mfg. of food-contact metallic... 

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