Primary surface active agents

ISO 894 1977, Surface active agents Technical sodium primary alkylsulfates—... 

Adsorption is one of the primary components of surfactant effectiveness. Surfactants are adsorbed on interfaces of the aqueous solution. That may be another solution which is immiscible with water, a gas phase, or a solid surface. Solid surfaces in particular are significantly altered by the adsorption of surface-active agents. Hence this effect is used in many fields. 

Spherical particles of various metal phosphate particles can be prepared by precipitation using urea as a homogeneous precipitation agent. Surface-active agents, such as SDS and CTAC, are effective in preparation of uniform-size spherical particles. The formed spherical particles are amorphous and contain OH- and H20, except cobalt phosphate particles with layered structure. These panicles are agglomerates of primary particles, and have pores of different sizes ranging from ultramicropore to mesopore. 

Lower aliphatic amines are widely used as intermediates for the synthesis of herbicides, insecticides and drugs or can be applied as rubber accelerators, corrosion inhibitors, surface active agents etc. [l]. The most widespread method for the preparation of lower aliphatic amines involves the reaction of ammonia with an alcohol or a carbonyl compound in the presence of hydrogen. The most common catalysts used for reductive amination of alcohols, aldehydes and ketones contain nickel, platinum, palladium or copper as active component [ I — 3 ]. One of the most important issues in the reductive amination is the selectivity control as the product distribution, i.e. the ratio of primary to secondary or tertiary amines, is strongly affected by thermodynamics. 

Application of surface active agents has demonstrated that kerogen forms a protective coating around the mineral matrix. This coating impedes the contacting of mineral with leachable liquid (1) and may be the primary cause of the impermeability and stress properties of the oil shale (2). 

As shown in Fig. 6 (A,B), the synthesis of the surface-active agent took place in the late-exponential phase, achieving its maximum value at the beginning of the stationary growth phase. Therefore, it can be concluded that the biosurfactant produced by B. subtilis ATCC 6633 is a primary... 

Some ingredients of eye medications may increase the permeability of the cornea. Surface-active agents are knovm to interact with membranes to increase the permeability benzalkonium chloride has surfactant properties and may well have some effect on comeal permeability, although its primary purpose is as a bacteriostat and bactericide. Chlorhexidine acetate and cetrimide, both of which are surface-active, are also used. 

Micelles are molecular aggregates formed in solutions of surface-active agents (surfactants compounds that orient at an interface such as between oil and water) (McAulifFe, 1980). Micelles may contain up to 100 or more surfactant molecules with a nonpolar (hydrophobic) end on the inside and a polar (hydrophilic) end on the outside. In 1959, Baker first advanced the concept of solubilization of hydrocarbons in (soap) micelles as a possible primary migration mechanism. The possible role of soaps, i.e. salts of organic acids, in primary migration was supported by Cordell (1973). The concept was considered attractive because it also explains how the practically water-insoluble hydrocarbons can solubilize in groundwater at relatively low temperatures. However, the likelihood of micellar solution as an effective primary migration mechanism has been seriously questioned by many authors (for instance Price, 1976 Hunt, 1979 Tissot and Welte, 1984). The main problems associated with micellar solution are ... 

Alkanolamides are condensation products of fatty acids with primary or secondary alkanolamines (Feairheller et al., 1994 Kopylov et al., 1980 Maltby Read, 2000). These products are nonionic surface-active agents and find application in a multitude of uses including dry-cleaning soaps, fuel-oil additives, rust inhibitors, textile scouring, and dye-leveling agents. 

This water-white, primary aliphatic amine is available commercially in an anhydrous form. It is soluble In water, methyl and ethyl alcohols, ethyl ether, ethyl acetate, aromatic and aliphatic hydrocarbons, acetone, mineral oil, fixed oils, oleic and stearic acids. It is soluble In hat paraffin and carnouba waxes, which solidify on cooling. It is potentially useful os on intermediate In such manufactured products as dyestuffs, surface-active agents, textile specialties, pharmaceuticals, bactericides, insecticides, and cleaning compounds. It is also used os o dehoiring ogent in the leather industry. 

This formulation is based on three surface-active agents, phospholipids (Lipoid E-80), poloxamer 188 and stearylamine, a cationic lipid with a pKa of 10.6 which contributes an overall positive charge to the oil droplet interfaces despite the anionic nature of the phospholipid combination over a wide pH range owing to its primary amine group. Other cationic surfactants and compounds, such as oleylamine, ° cetyltrimethylammo-nium bromide and chitosan were also proposed for confer-... 

Micas are hydrophilic and are thus compatible with polar polymers without surface treatment. But for best performance in polyolefins they are surface treated with silanes or surface active agents. Mica is considered the most effective mineral for reducing warpage and improving stiffiiess and heat deflection temperature. Its primary use is in polyolefins. 

International Organization for Standardization, Surface active agents—technical sodium primary alkylsulfates—methods of analysis, ISO 894 1977. Geneva, Switzerland. 

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