Wetting effectiveness

Masparov [53] and coworkers measured with lauryl alcohol ethoxylated with 6 mol EO a better detergency and wetting effect than with the corresponding polyoxyethylene ether carboxylic acid. 

Assist the widely dissimilar ingredients used in a rubber compound to coalesce and mix into a homogeneous uniform processable mass. Homogenisers are low-MW polymeric resin blends. The homogenising resin blend contains portions that are compatible with aliphatic, naphthenic and aromatic parts of the elastomers in a blend and higher-MW homologues of the plasticisers. They have a wetting effect. Fatty acid derivatives and phenolic resins are used. 

Formulation Properties which Enhance Wetting Effect of Operating and Formulation Variables... 

Naylor et al. (1993) studied the ability of lecithin to modify the rate and mechanism of dissolution of hydrocortisone in the presence of sodium taurocholate (NaTC) solutions. They found that in the presence of lecithin, the CMC of NaTC dropped owing to the more effective solubilization capacity of the mixed micelle. Furthermore, the CMC value dropped more on saturation with hydrocortisone, implying some interaction between hydrocortisone and the NaTC/lecithin micelles. These results indicated that in the NaTC-only system, wetting effects predominated dissolution, whereas in the NaTC/lecithin system, the dissolution rate of hydrocortisone was enhanced mainly through solubilization. 

When adhesives are used they must be in fluid condition during application, so that they can be transferred easily to the substrate from the containers in which they are stored, and caused to flow and to wet effectively the surfaces to be bonded. 

Wetting and detergency properties give rapid wetting, effective wax removal and good fabric rewettability whilst controlling the peroxide bleaching. Contains no silicate. 

Surface-active agents have been widely shown to enhance drug dissolution rates. This may be due to wetting effects, resulting in increased surface area, effects on solubility and effective diffusion coefficient or a combination of effects. Consequently surfactants have been included in tablet and capsule formulations to improve wetting and deaggregation of drug particles and thus increase the surface area of particles available for dissolution. 

With water as the wetting medium, the water/air surface tension is relatively high and it is necessary to apply a high pressure if small pores are present (145 bars for a pore radius of 0.01 pm) water can then be replaced by another liquid (e.g. alcohols or hydrocarbons). Nevertheless, as the method is dependent on the type of liquid used (different wetting effects), z-propanol is often used as a... 

Bakatselou, V., Oppenheim, R.C. and Dressman, J.B. (1991) Solubilization and wetting effects of bile salts on the dissolution of steroids. Pharmaceutical Research, 8 (12), 1461. 

In practical terms the coexistence conditions are determined as follows. A layer of some hundreds of nm thick of one of pure components (B say) is spin cast on a silicon wafer with a native oxide or covered with an evaporated metal. A similar layer of the other component (A) is laid on the top of the precast film B using standard [74] - or modified [91] (for hydrophobic polymers) - floating techniques. It is possible to ensure that the surface segregation and wetting effects do not perturb final phase configuration by arranging the surface preferred component to be located near this surface. Also the substrate may be modified (by metal evaporation) to cancel the possible polymer-substrate interactions... 

FIGURE 5.17 Flotation (a, c, e) and immersion (b, d, f) lateral capillary forces between two particles attached to fluid interface (a) and (b) are two similar particles (c) is a light and a heavy particle (d) is a hydrophibc and a hydrophobic particle (e) is small floating particles that do not deform the interface (f) is small particles captured in a thin liquid film deforming the interfaces due to the wetting effects. 

V. Oxidation catalysts have to be considered with a dynamical view under reaction conditions. This is related to the Mars and van Krevelen mechanism which involves a redox mechanism and also to the mobility of the oxide lattice. This dynamical phenomenon results in the wetting effect observed under catalytic reaction conditions for multicomponent and supported oxide catalysts [46, 47]. It follows that for many catalysts a certain time on stream is necessary before the catalyst reaches its steady state. It is frequent that in an industrial plant a... 

Adsorption of the surfactant onto the solid also makes this an unreliable method for determining the wetting effectiveness of dilute surfactant solution for powdered solids. Because of the small ratio of solution volume to solid-liquid interface, solutions that contain highly surface-active material that adsorbs well at the solid-liquid interface are rapidly depleted of surfactant and may penetrate more slowly than solutions of weakly surface-active material. 

Work on the wetting of hydrophobic sand by POE nonionics showed that both wetting rate and wetting effectiveness (measured by weight gain of the sand column) were greater for branched hydrophobic chain compounds than for linear ones (Varadaraj, 1994). 

A surprising facet of dry time and flow has appeared in several systems (7). Data indicate that flow and dry time are not necessarily in direct proportion. The wetting effects of the solvents also can influence flow. Returning to the polyamide inks, a flow test (described in Appendix A) was conducted on many of the inks. Evaluation of the flow in a pair of systems exhibiting 97-sec dry (ethanol) and 61-sec dry (60/40 ethanol/... 

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