Dispersion Properties

The introduction of monomers containing polar groups such as tertiary amines, imidazoles, pyrrolidones, pyridines, etc., gives the polymer dispersant properties that will be discussed in the article on dispersant additives for lubricants. 

The initial classification model of dispersion properties of engineering materials was obtained The algorithm of its creation includes ... 

The high index of refraction and dispersion properties of its oxide s have made germanium useful as a component of wide-angle camera lenses and microscope objectives. 

Reactions of the hydrocarbon chain in alkanoic acids include a-sulfonation and halogenation (51—54). The a-sulfonated fatty ester salts have excellent lime-dispersing properties and are valuable surface-active agents. 

Th. E. Tadros, The Effect of Polymers on Dispersion Properties, Academic Press, Inc., London, 1982. 

Uric acid is odourless in spite of three carbonyl groups, four trivalent nitrogen atoms and a double bond, and that it is similarly colourless in spite of four chromophores. Measurements of its refractive and dispersive properties indicate that it is a saturated body which suggests that molecular attraction exists between the various groups. 

The chemical treatment methods reduce dispersability property, of drilling fluids through the increase of size of cuttings which improves separation and prevents the buildup of colloidal solids in the mud. These methods include ionic inhibition, cuttings encapsulation, oil phase inhibition (with oil-base muds), and flocculation. The mechanical solids removal methods are based on the principles presented in Table 4-55. 

Einstein coefficient b, in (5) for viscosity 2.5 by a value dependent on the ratio between the lengths of the axes of ellipsoids. However, for the flows of different geometry (for example, uniaxial extension) the situation is rather complicated. Due to different orientation of ellipsoids upon shear and other geometrical schemes of flow, the correspondence between the viscosity changed at shear and behavior of dispersions at stressed states of other types is completely lost. Indeed, due to anisotropy of dispersion properties of anisodiametrical particles, the viscosity ceases to be a scalar property of the material and must be treated as a tensor quantity. 

Polyphosphinocarboxylic acid. Products based on this chemical tend to be suitable for brackish waters up to say 10,000 to 15,000 ppm TDS and where high sulfates are present (200 to 300 ppm as S04). A feature of this type of chemical is not only its ability to deal effectively with carbonate and sulfate scaling in higher TDS waters but also the fact that it has dispersant properties of benefit in physically moving potential foulants away from the membrane surface. 

Polymaleic acid (PMA). The use of chemicals based on PMA and some derivatives has become standard practice for very brackish waters and seawater distillation processes around the world, where the TDS may reach 50,000 ppm TDS, or where total hardness levels exceed 500 to 1,000 ppm CaC03. Its use in RO systems is growing. However, PMA has limited dispersing properties and may need to be formulated with a dispersant chemical to provide satisfactory performance with some RO designs. It is claimed that PMA is also a successful silica deposit control agent and therefore may be incorporated into formulations where this is a problem. 

PMA does not exhibit particularly good dispersion properties and under difficult conditions should be blended with a contaminant-... 

PCA 16 is available as Beldene 161/164 (50/35% w/w solids), Acumer 4161 (50%), and Polysperse (50%). These are low-phosphorus content materials that have found application in boiler FW formulations because of excellent sludge conditioning and particulate dispersion properties. The number 16 represents a 16 1 w/w ratio of acrylic acid and sodium hypophosphite, giving PCA 16 a MW range of 3,300 to 3,900. PCA 16 is particularly effective for the control of calcium carbonate and sulfate deposition. It is usually incorporated with other polymers in formulations and is approved for use under U.S. CFR 21, 173.310. 

Schulze [51] described an extensive study on C12-C14 ether carboxylic acid sodium salt (4.5 mol EO) in terms of surface tension, critical micelle concentration (CMC), wetting, detergency, foam, hardness stability, and lime soap dispersing properties. He found good detergent effect compared to the etho-xylated C16-C18 fatty alcohol (25 mol EO) independent of CaCl2 concentration, there was excellent soil suspending power, low surface tension, and fewer Ca deposits than with alkylbenzenesulfonate. 

The lime soap dispersing properties are, like all ethoxylated products, dependent on the fatty chain and the EO degree [61,64] a longer fatty chain and a higher EO degree improves the lime soap dispersing effect (Fig. 3). 

The COONa group in the ether carboxylate has a positive effect on the lime soap dispersing properties [61,64] (Table 4). Stroink [61] and Meijer [64] also describe the good acid, alkali, and electrolyte stability of some ether carboxy-... 

Due to the good lime soap dispersing properties it is possible to improve the foaming properties of hard water-susceptible surfactants. Improvement of the formulation of a fatty acid soap by laureth-17 carboxylic acid, sodium salt [57,62], and an amidether carboxylate [62] has been described. 

Because of improved mildness and lime soap dispersing properties ether carboxylates are also used in fatty acid soap-containing products like soap bars and liquid soaps [57,62] a foam improvement in hard water takes place. 

The lime soap dispersing properties are very important for the dispersal of Ca soap, which is used to achieve among others, lower foam [60,64,66,181]. In addition, nontoxicity as well as good dermatological properties and biodegradability have been factors in the increased use of ether carboxylates [60,66]. 

The ability to disperse the calcium soap formed from a given amount of sodium oleate has been studied for a number of a-sulfo fatty acid esters with 14-22 carbon atoms [28,30]. In principle, the lime soap dispersion property increases with the number of C atoms and the dissymmetry of the molecule. Esters with 14 C atoms have no dispersion power and in the case of esters with 15-17 carbon atoms the least symmetrical are the better lime soap-dispersing agents. However this property does not only depend on the symmetry but on the chain length of the fatty acid group. For example, methyl and ethyl a-sulfomyristate have better dispersing power than dodecyl propionate and butyrate. The esters with 18 and more carbon atoms are about equal in lime soap dispersion power. Isobutyl a-sulfopalmitate is the most effective agent under the test conditions. 

Stein and Baumann [14] studied the hydrolytic stability of MES and found the hydrolysis rate to be very slow in the pH range of 3-9.5 even at a temperature of 80°C. MES possesses good washing, foaming, and lime soap dispersing properties as well as ready biodegradability and a low acute oral toxicity. 

The effects of dispersion and birefringence on stellar interferometry will be discussed in Sections 17.2.3 and 17.2.4. New kind of fibres has been design to manage the dispersion properties using a silica / air structure. These fibres, so called Photonic Crystal Fibres, are very promising for many applications (Peyrilloux et al., 2002). 

Figure 3. Photonic Crystal Fibre (PCF). An air hole / silica arrangement allows to manage the dispersion properties.

By examining the dispersion properties of surface acoustic waves, the layer thickness and mechanical properties of layered solids can be obtained using the SAM. It can be used to analyze the wear damage progress [104], and detect the defects of thermally sprayed coatings [105]. 

By examining the dispersion properties of surface acoustic waves, the layer thickness and mechanical properties of layered solids can be obtained using the SAM. 

A considerable amount of work has already been successfully carried out in HASETRI with naturally occurring oils as eco-friendly process oils in conventional tire recipes [31,32]. These naturally occurring oils were found to be suitable on the basis of low PCA content. Some of the naturally occurring oils showed better processing properties, polymer-filler interaction, and dispersion properties in NR-based truck tire tread cap compound and hence better mechanical and dynamic mechanical properties. As the presently available low PCA oil in the market in the form of MES TDAE and naphthenic oil are comparatively costly, these natural oils can act as the best alternative processing aids for the elastomer industry, especially in developing and underdeveloped countries. 

The modification of bentonite with alkylsilanes improves the dispersing properties [991]. Incorporation of phosphonate-type compounds in bentonites for drilling mud permits the blockage of free calcium ions in the form of soluble and stable complexes and the preservation or restoration of the initial fluidity of the mud [1222]. The phosphonates also have dispersing and fluidizing effects on the mud. 

Physical mixtures consist of reversibly crosslinked and uncrosslinked hydrocolloid compositions and hydrocolloids. These show improved dispersion properties [1708]. 

Figure 5.39. Illustrating the focussing and dispersive properties of a magnetic prism in an electron energy-loss spectrometer. In a serial spectrometer a slit at D is used to ensure that only electrons of a single energy loss enter the detector. In a parallel spectrometer, a position-sensitive detector is placed at D to collect electrons of all energies in parallel.

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