As surface-active agents

Alkenylsuccinic anhydrides made from several linear alpha olefins are used in paper sizing, detergents, and other uses. Sulfosuccinic acid esters serve as surface active agents. Alkyd resins (qv) are used as surface coatings. Chlorendric anhydride [115-27-5] is used as a flame resistant component (see Flame retardants). Tetrahydrophthalic acid [88-98-2] and hexahydrophthalic anhydride [85-42-7] have specialty resin appHcations. Gas barrier films made by grafting maleic anhydride to polypropylene [25085-53-4] film are used in food packaging (qv). Poly(maleic anhydride) [24937-72-2] is used as a scale preventer and corrosion inhibitor (see Corrosion and corrosion control). Maleic anhydride forms copolymers with ethylene glycol methyl vinyl ethers which are partially esterified for biomedical and pharmaceutical uses (189) (see Pharmaceuticals). 

Other oxazolines synthesized from alkanolamines ate useful as surface-active agents and corrosion inhibitors. Synthetic oxazoline waxes promote lubricity and mat resistance of coatings. 

Soap is one example of a broader class of materials known as surface-active agents, or surfactants (qv). Surfactant molecules contain both a hydrophilic or water-liking portion and a separate hydrophobic or water-repelling portion. The hydrophilic portion of a soap molecule is the carboxylate head group and the hydrophobic portion is the aUphatic chain. This class of materials is simultaneously soluble in both aqueous and organic phases or preferential aggregate at air—water interfaces. It is this special chemical stmcture that leads to the abiUty of surfactants to clean dirt and oil from surfaces and produce lather. 

Long-chain alcohols, such as are obtained by the hydrogenation of coconut oil, polymerization of ethylene, or the 0x0 process (qv), are sulfated on a large scale with sulfur thoxide or chlorosulfuhc acid to acid sulfates the alkaU salts are commercially important as surface-active agents (see Surfactants). Poly(vinyl alcohol) can be sulfated in pyhdine with chlorosulfuhc acid to the hydrogen sulfate (84). 

Di- and Triisobutylcncs. Diisobutylene [18923-87-0] and tnisobutylenes are prepared by heating the sulfuric acid extract of isobutylene from a separation process to about 90°C. A 90% yield containing 80% dimers and 20% trimers results. Use centers on the dimer, CgH, a mixture of 2,4,4-trimethylpentene-1 and -2. Most of the dimer-trimer mixture is added to the gasoline pool as an octane improver. The balance is used for alkylation of phenols to yield octylphenol, which in turn is ethoxylated or condensed with formaldehyde. The water-soluble ethoxylated phenols are used as surface-active agents in textiles, paints, caulks, and sealants (see Alkylphenols). 

The product is a mistuie of various polyoxyethylene chain lengths (29—31). Glycol diesters ate used as vinyl plasticizers the monoesters as surface-active agents and viscosity modifiers for alkyd resins (qv). 

Sorbitol is the most important higher polyol used in direct esterification of fatty acids. Esters of sorbitans and sorbitans modified with ethylene oxide are extensively used as surface-active agents. Interesteritication of fatty acid methyl esters with sucrose yields biodegradable detergents, and with starch yields thermoplastic polymers (36). 

Experimental observations (S3) indicate that a stagnant cap is formed over the rear of the droplet as surface-active agents are added, and that this cap tends to enlarge with increasing concentrations until the entire droplet is enveloped. Thus, circulation may occur only in the front portion of the bubble. In contrast to this mechanism, Thorsen and Terjesen (T3) and Gamer (Gil) concluded that most of the mass transfer takes place at the rear of the bubble. 

In addition to temperature (which decreases y), the properties of interfaces are governed by the chemistry of the molecules present, their concentration and their orientation with respect to the interface. Solutes adsorbed at an interface which reduce interfacial tension are known as surface active agents or surfactants. Surfactants reduce interfacial tension by an amount given, under ideal conditions, by the Gibb s equation ... 

If as surface active agent with the reduction of 2- and 4-acetylpyridine the optically active proton-donating alcaloids strychninium or brucinium are adsorbed at the cathode, relatively high yields of optically active alcohol (benzhydrol) are obtained (234, 235). 

Organic esters are used as solvents, plasticizers, in resins, plastics, and coatings, as lubricants, in perfumes, flavors, cosmetics, and soap, as surface-active agents, as mcdicinals. and as herbicides and pesticides. 

SOAPS. Chemically, a soap is defined as any salt of a fatly acid containing 8 or more carbon atoms. Structurally a soap consists of a hydrophilic (water compatible) carboxylic add which is attached to a hydrophobic (water repellent) hydrocarbon. Soap molecules thus combine two types of behavior in one structure part of the molecule is attracted to water and the other part is attracted to oil. This feature underlies the function of these materials as surface active agents, or surfactants. Soaps are one class of surfactants. The other classes generally are called detergents. See also Colloid Systems and Detergents. 

Lubricants. A model for the lubrication mechanism has been developed lliat explains synergy between certain lubricants. Tins model neats lubricants as surface-active agents. Some lubricants have polar ends that arc attracted to other polar ends and to polar PVC flow units and to polar metal surfaces. These also have nonpolar ends that are repelled by the polar groups. Synergy happens when nonpolar Lubricants are added, which are attracted to the nonpolar ends and act as a slip layer. 

Oligoorganosiloxanes with alkoxyoxyalkylene fragments in their branches have recently been widely used as surface active agents, which regulate foam forming and foam stabilising in the production of various foamed polyurethanes. 

DEA is used as an intermediate for cosmetics as surface-active agents in household detergents and textile specialties in insecticides and herbicides in petroleum demulsifiers as a gas scrubber in refinery and natural gas operations in waxes, polishes and coatings emulsifiers in soluble oils and as corrosion inhibitors123. 

A similar strategy was reported by Asahi Glass which prepared fluoroacrylic (FA) diblock copolymem used as surface active agents [117]. Acrylates containing perfluorinated groups were telomerized with mercapto acetic acid followed by the condensation of the telomer produced with polypropylene oxide (PPO) to yield PPO-t-PFA diblock copolymers. 

As we know, the surface tension of water is high. When droplets of water fall on waxy surfaces, they tend to form small spheres. If a surfactant is added to water, surfactant molecules will displace some water molecules from the surface, which lowers the surface tension (Figure 2.7). As a result, the droplets can spread over the waxy surface and lose their spherical shape. Therefore, in addition to acting as surface-active agents in spray solutions, surfactants also lower the surface tension of water, thus increasing the area of contact. 

Fig. 185. Mannich bases as surface active agents (X, Z = substrate moiety).

Thiazetidine 1,1-dioxides or 3-sultams can be polymerized to high-molecular-weight polysulfonamides.l,2-Thiazetidin-3-one 1,1-dioxides react with aliphatic diamines to give polyamide-poly sulfonamide polymers. Fluorinated 3-keto and 3-imino derivatives were investigated as surface-active agents, and Ai-malonyl derivatives of l,2-thiazetidin-3-one 1,1-dioxide are said to be yellow couplers for color photography. ... 

This ester-type anesthetic is a combination of tetracaine HCl (2%), butyl aminobenzoate (2%), and benzocaine (14%). Benzalkonium chloride and cetyl dimethylammonium bromide are included as surface-active agents to facilitate the passage of benzocaine into the mucosal tissues. 

The nse of chlorobntanol is hmited to pHs below 6. It is snbject to thermal degradation and can be adsorbed on to the walls of containers. However, it has no major adverse effects. Chlorobntanol has no effect on wetting of the cornea or contact lenses, as surface-active agents do. When tested with soft lenses, chlorobntanol, concentrated in the lenses, canses mild conjunctivitis. 

Yi F P, Li J Z, Chen B. Study of ionic liquid as surface active agent. Acta Chim. Sina. 2008. 66, 239-244. 

The ability has been demonstrated to make a host of useful amido acid products, with applications as surface-active agents, specialty surfactants, food additives, chelating agents, and intermediates for sweeteners, etc. 

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