Grease acidity

An appreciation of the value of hydrous oxide colloids for wetting hydrophobic surfaces with water is shown by Kenney (593), who claims that certain aqueous particulate colloids can wet any known hydrophobic surfaces without chemical change. However, I have found that wetting by a silica sol occurs on certain hydro-phobic surfaces only at low pH and with an optimum particle size of silica. After the surface has been wetted by sol, rinsed, and dried, the area is rewettable only because there remains an adsorbed monolayer of silica particles bonded to the surface. The type of bonding depends on the type of hydrophobic surface. For example, a metal surface, hydrophobic because of an adsorbed film of fatty acids (grease) is made hydrophilic by the silica replacing some of the fatty acid and bonding to the oxide surface film until the area is well populated by silica. This occurs mainly at neutral... 

Chem. Descrip. Diethanolamine fatty acid condensate Uses Surfactant for all-purpose cleaners, liq. dishwashing, rug shampoos, laundry detergents, rinse acids grease emulsifier soil dispersant Features Can be compounded with liq. soaps and other syn. detergents Properties Liq. 

Lithium hydroxide with 12-hydroxy-stearic acid (or hydrogenated castor oil) they form the family of lithium greases very commonly used for general lubrication and bearing lubrication. 

Lime with tallow-derived fatty acids they are the so-called calcium greases that are often used as subframe greases and water-resistant greases. 

Sodium hydroxide with stearic acid they constitute the sodium greases, used in the lubrication of bearings under dry conditions and gear trains. 

The complex greases are obtained by the reaction of bases with mixtures of organic and/or inorganic acids. The three groups of complex greases are ... 

Calcium complex soap greases, obtained by the reaction of lime and a mixture of fatty acids and acetic acid. These greases offer good high temperature and anti-wear/extreme pressure properties related to the presence, in the soap, of calcium acetate that acts as solid lubricant they have good mechanical stability. 

Aluminum complex greases, obtained by the reaction of aluminum isopropylate with a mixture of benzoic acid and fatty acids. These greases have a remarkable resistance to water, very good adhesion to metallic surfaces, good mechanical stability properties and resistance to temperature. They are less common than the first two types. 

Sulfated ash in lubricating oils in greases NF T 60-143 ISO 3987 ASTM D 874 NF T 60-144 ASTM D 128 Weight of residue after treatment of the ash by sulfuric acid and calcination As above... 

Method B. Reduction with iron and hydrochloric acid. Place 40 ml. of water and 30 g. of grease-free iron filings (1) in a 750 or 1,000-ml. round-bottomed flask, and 25 g. (21 ml.) of nitrobenzene in a small beaker or conical flask. W arm the former on a water bnth at about 60°. Add... 

The formation of micelles and their properties are responsible for the cleansing action of soaps Water that contains sodium stearate removes grease by enclosing it m the hydrocarbon like interior of the micelles The grease is washed away with the water not because it dissolves m the water but because it dissolves m the micelles that are dis persed m the water Sodium stearate is an example of a soap sodium and potassium salts of other C12-C1S unbranched carboxylic acids possess similar properties... 

Potassium and sodium salts of long chain carboxylic acids form micelles that dissolve grease (Section 19 5) and have cleansing properties The carboxylic acids obtained by saponification of fats are called fatty acids... 

Eats and oils from a number of animal and vegetable sources are the feedstocks for the manufacture of natural higher alcohols. These materials consist of triglycerides glycerol esterified with three moles of a fatty acid. The alcohol is manufactured by reduction of the fatty acid functional group. A small amount of natural alcohol is also obtained commercially by saponification of natural wax esters of the higher alcohols, such as wool grease. 

Detergents may be produced by the chemical reaction of fats and fatty acids with polar materials such as sulfuric or phosphoric acid or ethylene oxide. Detergents emulsify oil and grease because of their abiUty to reduce the surface tension and contact angle of water as well as the interfacial tension between water and oil. Recent trends in detergents have been to lower phosphate content to prevent eutrification of lakes when detergents are disposed of in municipal waste. 

Water WVTR, O2 CO2 N, Acid Alkali Grease Organic Water Sunlight ... 

Dibasic acid esters and polyol esters are used as the bases in all aircraft jet-engine lubricants. They also are employed in aircraft greases that are subjected to wide temperature ranges. 

Petroleum. Apart from its use ia petrochemicals manufacture, there are a number of small, scattered uses of lime ia petroleum (qv) production. These are ia making red lime (drilling) muds, calcium-based lubricating grease, neutralization of organic sulfur compounds and waste acid effluents, water treatment ia water flooding (secondary oil recovery), and use of lime and pozzolans for cementing very deep oil wells. 

Various other soft materials without the layer—lattice stmcture are used as soHd lubricants (58), eg, basic white lead or lead carbonate [598-63-0] used in thread compounds, lime [1305-78-8] as a carrier in wire drawing, talc [14807-96-6] and bentonite [1302-78-9] as fillers for grease for cable pulling, and zinc oxide [1314-13-2] in high load capacity greases. Graphite fluoride is effective as a thin-film lubricant up to 400°C and is especially useful with a suitable binder such as polyimide varnish (59). Boric acid has been shown to have promise as a self-replenishing soHd composite (60). 

In the other market areas, lead naphthenates are used on a limited basis in extreme pressure additives for lubricating oils and greases. Sodium and potassium naphthenates are used in emulsiftable oils, where they have the advantage over fatty acid soaps of having improved disinfectant properties. Catalyst uses include cobalt naphthenate as a cross-linking catalyst in adhesives (52) and manganese naphthenate as an oxidation catalyst (35). Metal naphthenates are also being used in the hydroconversion of heavy petroleum fractions (53,54) and bitumens (55). 

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