Wetting power

Grafting of methylmethacrylate onto cellulose using ceric ammonium nitrate (Ce ) as the initiator in a benzene-water system is also demonstrated. The grafting yield in a benzene-water system is much lower than in the case of the methanol-water system and decreases by increasing the ratio of benzene to water. This can be due to the lower polarity and wetting power of benzene, which leads to poor swelling of the cellulose. 

Surface active agent. Any of a wide range of detergents, emulsifiers, dispersants, defoamers, etc., that tend to reduce the surface tension of water and improve its wetting power. 

Czichocki et al. [134] determined the wetting power of several pure and commercial alcohol ether sulfates. The values obtained for pure substances are shown in Table 26. As expected, shorter alkyl chain alcohol ether sulfates are better wetting agents than those having longer alkyl chains. 

Table 13 compares the wetting power of different sulfosuccinate diesters based on another method [69]. The classification is very similar to that mentioned in Table 12. 

The reaction of condensed phosphoric acid with castor oil gave a poly-phosphoric acid ester, which after neutralization with ammonia shows a high wetting power [32]. Glycerol trioleate was reacted with octametaphosphoric acid at 40°C in the presence of acetic acid anhydride. The reaction product was neutralized with triethanolamine [32,33]. 

The contact angle 0 of a liquid on a solid is the reflection of its wetting power. If 0 = 0, the liquid spreads freely on the solid surface and wets it. The relationship between the contact angle of a liquid on a solid and the surface tensions in the presence of saturated vapor of the liquid, is given by the Young s equation, Eq. (2). 

A method for comparing the wetting power of surfactants. It measures the time required for complete wetting of a piece of cloth or skein of yam placed at the surface of a surfactant solution, under specified test conditions. Different systems are compared in terms of their wetting times. See also Wetting. 

Pour point, viscosity, cloud point, wetting power and foam properties, being important advantages of SAE, are presented here in comparison with other commercial products derived from primary alcohols (Ziegler and Oxo) or nonylphenol (branched chain). 

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). 

Figure 8 shows temperature dependence of the wetting power of PAE, SAE and NPE each having about the same calculated HLB. 

It indicates a lower wetting power of PAE at lower temperatures and of NPE at higher temperatures compared with that of SAE. 

Properties Low Pour Point-Low Viscosity High Solubility Narrow Gel Range Good Wetting Power Good Foam Breakability... 

Figure 36. Wetting power of disodium sulfosuccinate half ester of Clt.lk secondary alcohol ethoxylates (SFT-MES-series). Test conditions surfactant concentration—0.1 wt % cloth—wool. ((-%-) SFT-MES-series (- -) LAS)...

In spite of their relatively high surface tension and poor wetting power, detergency tests show their better performance than LAS in non-built and comparable performance to LAS in built systems (Figure 39). 

The foam retains some of the properties of the phases that is formed from. For example, its compressibility is determined mainly by the ability of the gas to compress, and its wetting power by the properties of the foaming solution. At the same time, being a disperse system, the foam acquires the properties of a solid body maintains its shape, possesses a shear modulus, etc. 

Sodium alkanesulfonates are produced by photochemical sulfoxidation or sulfochlorination of suitable C12-C18 paraffin cuts. SAS can largely be substituted for LAS in formulations because of the similarity in terms of solubility, solubilizing properties, and wetting power [4]. 

The aim is to achieve good wetting of the hot mold surface by the emulsion. But good wetting is not sufficient. The projected emulsion droplets that touch the surface will first spread (wet), then partially splash and partially retract and finally rebound. So for optimum efficiency the droplet should have an excellent wetting power but at the same time a limited tendency for retraction and rebound. 

The compressibility of a foam is determined by (i) the ability of the gas to compress and (ii) its wetting power, which is determined by the properties of the foaming solution [4]. As with any disperse system, a foam may acquire the properties of a solid body - that is, it can maintain its shape and it possesses a shear modulus (see below). 

Sulphosuccinic acid diesters play a role above all in American polymerization formulations. They are rarely used as principal emulsifiers, but rather to control secondary properties, for example, for the production of highly concentrated low viscosity acrylate dispersions. The branched sodium di-2-ethyl hexyl sulphosuccinate is widely used, combining favourable emulsifier properties with excellent wetting power. Dicyclohexyl sulphosuccinate has a particularly high CMC and a particularly high surface tension [48]. 

---