Wetting ability

Chlebicki and Slipko [127] also determined the wetting ability of series of sulfated propoxylated alcohols. The introduction of propylene oxide groups... 

The applications of a-sulfo fatty acid esters are widely spread as for other surfactants. They can be used in detergents, cleansers, and cosmetic products as well as in the building industry and for the production of synthetic materials and agrochemicals. The main properties for these applications are surface activity, wetting ability, hard water stability, lime soap dispersion power, and good human and environmental safety profiles. 

The wetting ability of the anode electrode was evaluated as the contact angle measured by the capillary rise method. The value of fractal dimension of anode electrode of MCFC was calculated by use of the nitrogen adsorption (fractal FHH equation) and the mercury porosimetry. 

The wetting ability of an MCFC electrode is closely related to the performance of cell operation especially including electrochemical reaction, and can be expressed as contact angle between electrolyte and electrode. The surface energy of 3 phases, geometric structure of anode electrode and... 

Physically, the wetting abdity increases (the contact angle decreases) as the values of the fractal dimension of the electrode increases if the electrode material is same. However, in this study, we could not obtain a good correlation between the fractal dimensions and the wetting abilities as shown in Table 1. It means that not only the physical properties such as the surface irregularity and roughness but also the chemical interaction between electrolyte and electrode were important in wetting ability. 

With the experimental results about the wetting ability and the fractal dimension of four kinds of anode electrodes, we could conclude the following. The addition of NisAl could make the electrolyte wet the electrode very well. The pore structures of all the electrodes prepared in this study were highly irregular and rough. Finally, the chemical properties of the surfaces were as important as the physical properties in determining the wetting ability of the electrodes in this study. 

The heads of the stopcock molecules must be large enough so that they cannot enter the channels. They should fulfill the stability criteria imposed by a specific application and it should be possible to functionalize them in order to tune the properties of the surface (e.g., the wetting ability, refractive index matching, and... 

Heats of immersion provide a new tool for rating the wetting ability of surfactants from aqueous solution. If a high-area graphite, Graphon, or carbon black is used, the increased heat effect obtained with the surfactant solution over that obtained with water allows the wetting tendency of the surfactant to be rated (71). Typical heats of immersion in surfactant solutions are listed in Table IX. 

Sodium fatty acid ester sulfonates are known to be highly attractive as surfactants. These have good wetting ability and excellent calcium ion stability as well as high detergency without phosphates, and are used in powders or liquids. They can also be used in the textile industry, emulsion polymerization, cosmetics, and metal surface fields. Moreover, they are attractive because they are produced from renewable natural resources and their bio degradability is almost as good as alkyl sulfates (134—137). 

Two other properties of the liquid phase to be considered are viscosity and wetting ability. Ideally liquid phases should have low viscosity and high wetting ability (ability to form a uniform film on the solid support). 

Wetting Power. Figure 7 shows plots of wetting time against Griffin s HLB for various nonionics. Better wetting abilities of SAE compared with PAE are seen as in previous papers by MacFarland(5) and by ZikaO, 18). 

Dale and Ludwig (9) also investigated the use of glass-fiber mats and had difficulty in wetting the fibers with molten sulfur, but including a modifier (e.g., a terpene) improved the wetting ability and also increased the strength of the composite. 

Best surfactant behaviour was achieved in the case of the polyether trimethylsilane by introducing a hexyl spacer group in the molecule structure. For testing the wetting ability a droplet (50 pi) of an aqueous surfactant solution is applied by syringe to a clean sheet of polypropylene. Afterwards the increase of the diameter of the droplet is measured. The surface tension of the aqueous solution is usually determined by the well known ring method of du Nouy [5]. 

Figure 8 The contact angle between a solid and a liquid arises from differences in surface tensions and is used for a quantitative measurement of wetting ability...

Other Vinyl Derivatives. PVP is a nonionic surfactant used in 3% to 5% concentrations to increase viscosity of solutions. Although it exhibits surface-active properties similar to the cellulose ethers, PVP appears to have less abiUty to lower the interfacial tension at a water-oil interface. Nevertheless, in contrast to the cellulose ethers, PVP appears capable of forming hydrophilic coatings in the form of adsorbed layers. Because conjunctival mucin is believed to interact with the ocular surfece to form an adsorbing surface for aqueous tears, the formation by artificial means of a hydrophilic layer that would mimic conjimctival mucin (mucomimetic) appears to be clinically desirable. Both mucin- and aqueous-deficient dry eyes would benefit, because the wetting ability of the corneal surfece would be enhanced. 

MERCERANT BEA is a non-phenolic, non-staining mercerizing assistant having excellent wetting ability in 18-25% caustic soda at room temperature. 

Both Hercolyn and Abalyn combine the solvent power of abietic acid with that of a methyl ester. Thus, they may act ar. resins and as plasticizers. Both possess excellent wetting ability, even for nonporous materials such as ass and metals. Hercolyn was proposed (Refs 2 3) as a coating for NC proplnt grains Refs 1) Beil — does not list abietic acid (abi-etinsaure) or methyl-abietate 2) E.S. Goodyear, USP 2147698 (1939) CA 33, 4040 (1939) 3) H.M. Spurlin G.H. Pfeiffer, USP... 

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