Surfactant penetration

Edelhauser (3) has explained his results on the interaction of anionic surfactants (sodium lauryl sulfate and sodium dodecyl-benzene sulfonate) with a PVAC latex as a two-step mechanism involving surface adsorption followed by surfactant penetration into... 

Latex thickening, a result of surfactant penetration and solubilization of the polymer, increases with the vinyl acetate content of vinyl acetate-butyl acrylate co-polymer latexes. 

Solid soils are commonly encountered in hard surface cleaning and continue to become more important in home laundry conditions as wash temperatures decrease. The detergency process is complicated in the case of solid oily soils by the nature of the interfacial interactions of the surfactant solution and the solid soil. An initial soil softening or "liquefaction", due to penetration of surfactant and water molecules was proposed, based on gravimetric data (4). In our initial reports of the application of FT-IR to the study of solid soil detergency, we also found evidence of rapid surfactant penetration, which was correlated with successful detergency (5). In this chapter, we examine the detergency performance of several nonionic surfactants as a function of temperature and type of hydrocarbon "model soil". Performance characteristics are related to the interfacial phase behavior of the ternary surfactant -hydrocarbon - water system. 

Changes in the fingerprint region of the spectra can also be related to surfactant penetration. The frequency and shape of the 8, CH2 band are very sensitive to intrachain interactions The CH2 wagging defect modes and the C-0 bands of the surfactant appear in this region as well. 

The results obtained with C19 and as model soils suggested that the crystal form of the hydrocarbon can affect surfactant penetration and hence removal. Hexacosane (C26), with a melting point of 57 °C, allows investigation of the effect of temperature over a wider range than the systems described above. Additional details about the relationship of surfactant phase behavior to solid soil removal can be obtained, and the efficiency of the displacement mechanism can be explored further, using C2g as a model soil. 

Adsee . [Witco/Organics] Edioxylated ethers agricultural surfactant penetrant... 

Chemtex. [Chem-Tex Labs] Surfactants, penetrants, scouring agents, binders, antifoams, ieverlers, retarders, softeners, lubricants, oxidizing agents, emul-sifien for tactile tq>plics. 

HEC has found limited use as a thickener for cosmetic formulations. Modification of this polymer with small amounts of tetramethylamine functionality expanded its end use by providing substantivity to hair and inhibiting surfactant penetration of human skin (37). Hydrophobic modification of quaternary HEC increases the polymer s surface activity (38) as reflected in its foam stability (Figure 7). 

We concluded that formation of the cationic-anionic complex inside the cuticle is necessary to produce this effect. If the cell membrane complex is damaged (e.g., by permanent waving), then penetration is enhanced. Adsorption of the cationic species occurs inside the cell membrane complex and the endocuticle. On washing with the anionic surfactant, penetration occurs, and an insoluble cationic-anionic complex deposits inside the cell membrane... 

Chem. Descrip. Special phenol ethoxylate Uses Surfactant penetrant detergent solubilizer polymerization emulsifier wetting agent, dispersant for pigments Features Stable to alkali, metallic iron, peroxide good flowability and lubrication... 

The first step, just after wetting, is to attack the oily—greasy component. Surfactants made available by adsorption will directly cope with the oily part of the soil, whereas solid parts will be liquefied by surfactant penetration [59]. Although cleaning per se is not the purpose of this chapter, it is worthwhile to highlight similarities between the wetting of a solid surface coated with oily soil and the flotation process. 

The cell types. Many tests are developed with fibroblasts (cells from the dermis) or with transformed cell lines for convenience of culture. Others employ kera-tinocytes (cells from the epidermis) because they are the first living target encountered by surfactants penetrating the skin. Finally, in order to involve intercellular communications in cell response to irritants, fibroblasts and keratin-ocytes have been cocultivated. 

There is no simple explanation of the absorption-promoting effect of the surfactant. Penetration of the surfactant into the liquid membrane seems to be... 

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