Polymeric surfactants, definition

In summary, it appears that the adsorption of proteins at fluid/fluid interfaces is very complex and involves several steps that are not encountered in classical surfactants or even polymeric surfactants. All the parameters that are controlling the surface activity may be changed by chemical or physicochemical modifications, such as covalent attachment of various groups, breaking of disulfide bonds, de-naturation by heat, etc. It is important to note that while changing one parameter, one may change the others as well, and therefore it would be difficult to isolate definite parameters. 

The position of point A in the curve shown in Fig. 1.7 is characteristic for a sufficient purity of the surfactant and solvent. The point is located at a definite surface tension and concentration (CMC). As a rule, a minimum in the y(c) or y(log c) plot is evidence of traces of highly surface-active impurities which affect the results [147]. In chapters 2 to 4 the effect of lateral molecular interaction with increasing alkyl chain length, the effects of changes in orientation and conformation, essentially shown by polymeric surfactants such as proteins, may also lead to significant changes in the adsorption behaviour. 

Definition PEG ether of cetearyl alcohol Formula R(OCH2CH2)nOH, R = blend of cetyl and stearyl radicals, avg. n = 50 Properties Nonionic Toxicology TSCA listed Uses Wetting agent, detergent for industrial/domestic applies. emulsifier, foam control agent in syn. heavy-duty detergents emulsion polymerization surfactant, emulsifier in cosmetics emulsion stabilizer in food-contact textiles... 

Synonyms PEG-50 sorbitol hexaoleate (INCI) POE (50) sorbitol hexaoleate Definition Oleic acid hexaester of ethoxylated sorbitol with an avg. 50 moles EO Properties HLB 11.4 nonionic Uses Emulsifier, coupling agent for cosmetics, textiles, metalworking fluids, polymerization surfactant for foods, feed, pharmaceuticals in resinous/polymeric food-contact coatings Reguiatory FDA 21CFR 175.300 Trade Name Synonyms Atlas G-1096 [Uniqema Uniqema Am. http //www.uniqema.com], Ethox HO-50 [Ethox http //www.ethox.com], Hedipin-SHO/500 [Dr. 

PEG 300 tridecyl ether phosphate POE (6) tridecyl ether phosphate Definition Complex mixture of esters of phosphoric acid and trideceth-6 Properties Anionic Toxicology TSCA listed Uses Pesticide emulsifier dry-cleaning detergent textile wetting agent, antistat penetrant, lubricant for fiber and metal treatment emulsion polymerization surfactant in cosmetics emulsifier in mfg. of food-contact articles in lubricants for incidental food contact... 

Polymeric surfactants are, by definition, surface active. On the other hand, not all surface active polymers are amphiphilic. In effect, every polymer is surface active in the sense that it shows a strong tendency to adsorb. This, as we discussed, is a consequence of the polymerization the translational entropy per monomer decreases as l/N while the interaction energy between a monomer and the surface is roughly independent of N. Polymeric surfactants are distinguished by their ability to self-assemble because of microphase separation. 

Control of the particle size while retaining precise control over the release rate is enabled by compartmentalization of the sol-gel solution into droplets of definite size. This can be achieved by emulsification of the sol-gel solution by mixing it with a solution composed of a surfactant and a non-polar solvent (Figure 2.13). When an active molecule is located in the aqueous droplet of a W/O emulsion, encapsulation occurs as the silicon precursors polymerize to build an oxide cage around the active species. By changing the solvent-surfactant combination, the particle size can be varied from 10 nm to 100 pm as the size of the particles is controlled by the size of the emulsion droplet, which acts as a nano-reactor for the sol-gel reaction (Figure 2.13). 

When chloro-octadecane was found to give the same result as a so-called cosurfactant, an argument arose in terms of the real role of this highly hydrophobic compound because it is not surface active and has no cooperation with surfactant. Taking account of these systems, the definition of miniemulsion polymerization will be revised to the polymerization in which a water-insoluble compound in the dispersed phase retards or inhibits diffusion degradation of the emulsion. ... 

The most general definition of a template is as a structure-directing agent. In surfactant solutions the final templated polymers can be either discrete nanoparticles or mesostructured bulk materials as a consequence of polymerization, respectively, in the non-continuous or continuous domains of the template. Thermodynamically stable media, such as microemulsions, equilibrium vesicles, or lyotropic mesophases are especially useful as templates because of their structural definition and reproducible morphologies. The mesostructure of a thermodynamically stable template is defined by composition and temperature, but this same feature makes the structure unstable to changes in temperature, pH, or concentration. The aim of template synthesis is to transfer the self-organized template structure into a mechanically and chemically stable, durable, and processable material. 

The most significant distinction between the two classes of semi-batch process is, therefore, that an emulsion addition process necessarily involves the addition of smfactant throughout the particle growth period during which monomer is added. In the strict definition of a monomer addition process, the surfactant is introduced completely at the outset of the polymerization however, it is more usual for surfactant to be added during the reaction (to ensure colloidal stability as the particles grow), but normally as a separate input stream. 

Synonyms Methacrylate copolymer Methacrylate polymer Definition Fully polymerized copolymer of methacrylic acid and an acrylic or methacrylic ester Type C may contain surfactants Properties Wh. powd., faint char, odor sol. in dll. alkali, buffer sol ns. of pFI 7, methanol, alcohol, IPA, acetone insol. in water, dll. acids vise. 50-200 cps... 

Definition Mixture of oleate esters of sorbitol and sorbitol anhydrides, with 20 moles ethylene oxide Properties HLB 11.0 nonionic Toxicology Human skin irritant TSCA listed Uses Surfactant, emulsifier, solubilizer for polymerization, cosmetics, phamfiaceuticals, agric., textiles, paints, pulp/paper, metalworking plastics solubilizer for perfume, flavors, essential oils food emulsifier, stabilizer lubricant antistat vise, modifier suspending agent emulsifier in food pkg. 

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... 

Classification Linear alcohol ethoxylate Definition PEG ether of a mixt. of syn. C9-11 fatty alcohols with avg. 3 moles EO Properties Nonionic Toxicology TSCA listed Uses Surfactant emulsifier in cosmetics intermediate dispersant wetting agent for household/industrial detergents, cosmetics, textiles, leather, agric., paints/coatings, emulsion polymerization, lubricants, silicon and wax emulsions, metal treatment, paper processing... 

Definition Disodium salt of an oleyl alcohol half ester of sulfosuccinic acid Empiricai C22H40O7S 2Na Uses Surfactant, cleansing agent in cosmetics foaming agent for rubber latex compds. emulsifier for emulsion polymerization Trade Name Synonyms Em pi min MTT/A... 

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