Surface cleaning properties

Figure 11.18 illustrates the excellent hard surface cleaning properties of biosurfactants as compared to two commonly used surfactants LES and APG650. Especially sophorolipids ( Sopholiance ) are highly effective and certainly in concenttated applications (1/10, or 0.5%, of active substance). In very diluted applications (1/1000, or 0.005%, of active substance) the difference between surfactants levels out, contrary to... 

The detergent range alcohols and their derivatives have a wide variety of uses ia consumer and iadustrial products either because of surface-active properties, or as a means of iatroduciag a long chain moiety iato a chemical compound. The major use is as surfactants (qv) ia detergents and cleaning products. Only a small amount of the alcohol is used as-is rather most is used as derivatives such as the poly(oxyethylene) ethers and the sulfated ethers, the alkyl sulfates, and the esters of other acids, eg, phosphoric acid and monocarboxyhc and dicarboxyhc acids. Major use areas are given ia Table 11. 

Metal surface cleaning, by virtue of (limited) sequestration, dispersing, surface-acting, and detergent properties. 

Additionally, the surfactant properties of filmers reduce the potential for stagnant, heat-transfer-resisting films, which typically develop in a filmwise condensation process, by promoting the formation of condensate drops (dropwise condensation process) that reach critical mass and fall away to leave a bare metal surface (see Figure 11.2). This function, together with the well-known scouring effect on unwanted deposits keeps internal surfaces clean and thus improves heat-transfer efficiencies (often by 5-10%). 

Under ambient atmospheric conditions a native oxide is formed on cleaved Si surfaces. The properties of native and chemical oxides are discussed in Section 5.2. The well-defined surface conditions produced by wet processes like rinsing and cleaning procedures will be discussed below. 

Most earlier papers dealt with the mercury electrode because of its unique and convenient features, such as surface cleanness, smoothness, isotropic surface properties, and wide range of ideal polarizability. These properties are gener y uncharacteristic of solid metal electrodes, so the results of the sohd met electrolyte interface studies are not as explicit as they are for mercury and are often more controversial. This has been shown by Bockris and Jeng, who studied adsorption of 19 different organic compounds on polycrystaUine platinum electrodes in 0.0 IM HCl solution using a radiotracer method, eUipsometry, and Fourier Transform Infrared Spectroscopy. The authors have determined and discussed adsorption isotherms and the kinetics of adsorption of the studied compounds. Their results were later critically reviewed by Wieckowski. ... 

Furstner R, Barthlott W, Neinhuis C, Walzel P (2005) Wetting and self-cleaning properties of artificial superhydrophobic surfaces. Langmuir 21 956-961... 

The tendency of mica to cleave easily along the (100) crystallographic plane results in smooth,clean reproducible surfaces. This property, coupled with good thermal stability, has led to its wide use as a substrate in surface chemical studies (2). Indeed, the ability of Muscovite mica to be cleaved to give atomically smooth surfaces over areas of several square centimeters... 

Applications. At present there are very few known applications, although the surfactants have significant potential due to their unique properties. Sulphonated fatty acids are used in some hard-surface cleaning formulations where their low foam is a benefit and in emulsion polymerisation, where they perform similarly to LAS but with greatly reduced tendency to foam. Future applications for these products may include machine dishwash, extended use in detergent products and industrial applications such as pigment dispersants. For these to be realised, further process development will be required to give a more consistent and better defined product. 

GlucoponR 215 CS UP Capryl glucoside 62-65% Hard surface cleaning Good wetting and dispersing properties... 

All the techniques discussed so far refer to clean surfaces or surfaces with adsorbed molecules. When thicker adsorbed layers are present on the surface, the properties of these layers start to resemble those of the corresponding bulk phases. For Instance, for thin water layers on solid surfaces the dielectric permittivity (bulk water. A more or less gradual transition takes place towards wetting films to which we shall return in Volume III and. as far as multilayer adsorption is concerned, in sec. 1.5 g, h. 

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