Soaps that form association colloids are effective drag-reducing agents in nonaqueous fluids, while simultaneously building the desired viscosity characteristics of the fluid. Such agents, while effective in a drag-reduction sense, are sensitive to trace amounts of water and catalyze the oxidative degradation of oils at elevated temperatures.Association colloids of soap type were the first agents observed to decrease the frictional drag of fluids in turbulent flow. During World War 11, Mysels and coworkers (Agoston et al., 1954) discovered that under turbulent flow conditions decreased pressure drops were found for gasoline slightly thickened with Napalm when compared with ordinary gasoline at the same flow rate. Napalm, the drag-reducing ingredient, is primarily an aluminum disoap corresponding to the approximate formula Al(OH)R?, where R refers to a mixture of commercial coconut, oleic, and naphthenic acids. While the mechanism of drag reduction is not yet fully understood, no chemical drag-reducing agents are yet known which do not possess good dispersibility in the subject solvent, high molecular weight, and extended molecular structure. Soluble, high molecular weight polymers having essentially linear molecular structures are good examples of drag-reducing agents in both aqueous and nonaqueous media. Oil-dispersible polar molecules of the soap type are considered also to conform to these requirements through molecular association of the soap "monomer" units to form extended linear structures of high molecular weight (Figure 1).While high molecular weight polymers of linear structure are much more efficient drag-reducing agents than the soap-type association colloids, association colloids possess the unique virtue of being able to reheal their dragreducing linear structures after passing through regions of intense shear. This ability to regenerate the dragreducing species makes association colloids emminently suitable for use in closed systems involving high shear pumping devices.In 1966 it was reported that the use of drag-reducing additives in hydraulic fluids might improve the efficiency of power transmission in hydraulic systems (Pruitt and Crawford. 1965). Soap-type additives might be used for such purposes. Prior research, however, showed that the physical properties of carboxylate soaps in organic liquids are strongly affected by polar impurities such as water To whom correspondence should be sent. and acids. Specifically, Singleterry (1954. 1956) in their studies of phenyl stearate soaps in benzene, found that the soaps of different metals were different in their responses to the addition of polar materials. The viscosities of lithium soap solutions remained high in the presence of small quantities of water. while the sodium and potassium soap solutions rapidly decreased in viscosity. Thus, the chains or aggregations of soap molecules, presumed to be the active species in reducing fluid friction in turbulent flow, would be more stable in the presence of water if they were lithium rather than sodium...
Maintenance and renewal of complex electrical and electronic equipment can be greatly simplified with the aid of basic surface chemistry.The authors discuss the theoretical aspects of surface chemistry appropriate to such maintenance and describe some proved methods for restoring damaged equipment to use As a result of equipment damage in floods, hurricanes, tornadoes, heavy rains, and rapid thaws, millions of dollars of damage are done annually to homes, factories, and equipment of all kinds. Immersion in water is particularly serious for electrical power plants, motors, controls, radios, radars, and other electronic devices, switchboards, automobiles, machinery, tools, and instruments. Class of Liquid .Sfco, Dynes/cm. at 201 Paraffins (C8 to Cm) 3.5 to -3.0<* Aromatic hydrocarbons (benzene and propylbenzene) 5.5 to 9.9" Cycloparaffins Zero or less" Ketones (C3 to Cm) 26 to 46 Esters (various types) 30 to 43 Alcohols (C3 to C,7) 15 to 50 Ethers (Ce to Cm) 18 to 31 Ether alcohols from glycols Data were obtained at 25°C. 36 to 42and thus accelerate greatly the drying process, (3) aggressive chemical cleaners to remove corrosion products not otherwise removed, and (4) special techniques for facilitating the chemical salvaging process.
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