Wetting properties, colloids

Kim, E.H.J. Chen, X.D. Pearce, D. Surface characterization of four industrial spraydried dairy powders in relation to chemical composition, structure and wetting property. Colloids and Surfaces, B Biointerfaces, 2002,26(3), 197-212. 

Elzbieciak, M., M. Kolasinska, and P. Warszynski. 2008. Characteristics of polyelectrolyte multilayers The effect of polyion charge on thickness and wetting properties. Colloids Surf. A Physicochem. Eng. Asp. 321 258-261. 

Microstructures of CLs vary depending on applicable solvenf, particle sizes of primary carbon powders, ionomer cluster size, temperafure, wetting properties of carbon materials, and composition of the CL ink. These factors determine the complex interactions between Pt/carbon particles, ionomer molecules, and solvent molecules, which control the catalyst layer formation process. The choice of a dispersion medium determines whefher fhe ionomer is to be found in solubilized, colloidal, or precipitated forms. This influences fhe microsfrucfure and fhe pore size disfribution of the CL. i It is vital to understand the conditions under which the ionomer is able to penetrate into primary pores inside agglomerates. Another challenge is to characterize the structure of the ionomer phase in the secondary void spaces between agglomerates and obtain the effective proton conductivity of the layer. 

Ananthapadmanabhan KP, Goddard ED, Chandar P (1990) A study of the solution, interfacial and wetting properties of silicone surfactants. Colloid Surf 44 281-297... 

In many cases it is necessary to synthesize porous materials in a well-defined preordered shape or within confined geometries, which introduces a pathway to fabricate hierarchically ordered porous materials. The techniques mentioned above have been shown to be capable of producing structured and well-ordered templates [61] within capillaries [50], thin plates [62], micromolds [63], or photoresist patterns [64,65]. Spatial adjustment of the surface functionality on the substrate and its wetting properties can yield patterned colloidal films [66,67]. Finally, confining the particle dispersion itself by printing techniques produces micropatterned arrays [68]. This was also shown to work without the necessity of preceding surface patterning steps [69]. 

PVAc in the presence of Mercaptan of the alkanes modifier for surface tension and wetting property protective colloid... 

The wetting properties of the substrate can infiuence the superlattice morphology [19[. For example, if the colloidal solution of nanoparticles wets the substrate, then a 2-D superlattice will grow preferentially, forming a monolayer. As the surface coverage increases, however, the nanocrystals vfill adsorb to the ledges and kinks of the growing structure, so as to form terraces that extend laterally across the substrate. 

K. P. Anathapadmanabhan, E. D. Goddard, P. Chandar A Study of the Solution, Interfacial and Wetting Properties of Silicone Surfactants , Colloids and Surfaces 1990, 44, 281-297. 

Bismarck A, Kumru ME, Springer J, Influence of oxygen plasma treatment of PAN based carbon fibres on their electrokmetic and wetting properties, J Colloid Interface Sci, 210(1), 60-72, 1999. 

In solvent-borne rubber adhesives, a variety of solvents can be chosen to control drying rate, adjust viscosity and dissolve important ingredients. Resins can be added to improve tack, wetting properties, heat resistance, bond strength and oxidation resistance. The most common resins nsed in rubber-based adhesives are rosins, rosin esters, and terpene, coumarone-indene, hydrocarbon and phenobc resins. Plasticizers and softeners reduce hardness, enhance tack and decrease cost of rubber adhesive formulations. Paraffinic oils, phthalate esters and polybutenes are typical plasticizers. Fillers are not often added to rubber adhesive formulations because they reduce adhesion. However they are sometimes used because they decrease cost and increase solution viscosity. Carbon black and titanium dioxide are also used to provide colour to the adhesives. Clays, calcium carbonate and silicates are also common fillers in rubber adhesive formulations. For water-borne adhesives, typically protective colloid, preservative, defoamers, wetting agents and emulsifiers are included in the formulations. 

As we already said, the immobilization of particles on the surface is driven by the combined effects of capillary forces, both that drive meniscus deformation (and consequently particle confinement in the trapping structure) and that are exerted on the particles during meniscus break-up. Consequently, the assembly process must be sensitive to both the wetting properties of the colloidal suspension and the shape and dimension of the trapping structures. 

We will first consider the influence of the wetting properties of the colloidal suspension relative to a given substrate. The role of surface tension on the yield of the assembly process can be easily investigated by adding a well-defined concentration of surfactants in the initial suspension. As an example, it was shown that the assembly of 500 nm PS particles on a PDMS substrate was optimum for a contact angle ranging from 30° and 60°. ... 

Karbowiak, T., Debeaufort, F., Champion, D. Voilley, A. (2006). Wetting properties at the surface of iota-carrageenan-based edible films. Journal of Colloid and Interface Science, Vol. 294, No. 2, pp. 400-410, ISSN 0021-9797. 

Song W, et al. Silver microflowers and large spherical particles controlled preparation and their wetting properties. J Colloid Interface Sci 2007 311(2) 456-60. 

The surface-active agents (surfactants) responsible for wetting, flotation and detergency exhibit rather special and interesting properties characteristic of what are called association colloids or, in the older literature, colloidal electrolytes. These properties play an important role in determining, at least indirectly, the detergency of a given surfactant and are therefore considered here... 

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