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Paints interfacial tension

Several components of the organic phase contribute greatly to the character of the final product. The pore size of the gel is chiefly determined by the amount and type of the nonsolvent used. Dodecane, dodecanol, isoamyl alcohol, and odorless paint thinner have all been used successfully as nonsolvents for the polymerization of a GPC/SEC gel. Surfactants are also very important because they balance the surface tension and interfacial tension of the monomer droplets. They allow the initiator molecules to diffuse in and out of the droplets. For this reason a small amount of surfactant is crucial. Normally the amount of surfactant in the formula should be from 0.1 to 1.0 weight percent of the monomers, as large amounts tend to emulsify and produce particles less than 1 yam in size. [Pg.164]

Leafing and Nonleafing. Leafing pigments float on the surface of paint or printing ink films as a result of high interfacial tension. They form a coherent surface film whose reflective properties depend on the particle fineness. Stearic acid is the lubricant usually used in the manufacture of these products. [Pg.229]

Aqueous viscosity was measured at room temperature with a Brookfield and Ubbelohde viscometer. Intrinsic viscosities were measured by a five-point dilution method no shear-rate corrections were made for the data. Interfacial tension was measured with a DuNouy ring tensiometer against toluene at various polymer concentrations. The formulations used to evaluate the HMHECs for latex paints have been described elsewhere (5). [Pg.344]

If both E and are positive, the defoamer penetrates into the foam lamella and spreads across the surface. This creates interfacial tension differences that destabilize the lamellae and cause the foam to collapse. In simple terms it can be said that defoamers act because of their controlled incompatibility with the paint system. If a defoamer is too compatible its defoaming effect is not sufficient, if it is too incompatible film defects occur (e.g., gloss reduction, formation of craters). [Pg.160]

Many surface defects can be explained by differences in interfacial tension. Poor substrate wetting, for example, must be expected if the paint has a higher surface tension than the substrate to be coated. When spray dust or solid dust particles fall onto a freshly coated surface, craters are formed if the deposited droplets or particles... [Pg.163]

Uses Surface tension reducer, interfacial tension reducer, wetting agent, dispersant, emulsifier, penetrant, solubilizer for cosmetics, detergents, agricultural, mining products, textiles emulsifier, dispersant for water treatment, paints, inks, polymerization Properties Sp.gr. 1.06 anionic 70% total solids Colawet DOSS 70S [Colonial Chem.]... [Pg.202]

To prevent cissing, an additive that reduces interfacial tension is required in the paint. When interfacial tension falls, the particle is wetted by the finish and absorbed into the film. Surface-active agents Surfactants, see below) reduce interfacial tension. Alternatively, an agent can be added that will reduce the liquid surface tension so much, that the interfacial tension also becomes low. Silicone oils do this effectively. Very little silicone oil is required, because it finds its way almost entirely to the surface. Silicones are semi-organic compounds... [Pg.131]

Thus one end of the surfactant molecule is attracted to polar molecules (e.g. water) and polar surfaces, while the other prefers a nonpolar environment. If we have the problem of two materials which will not wet or make chemical contact with one another, surfactants can bridge the gap. In the example already discussed under cissing , we will assume that tiny oily particles are dropping on to the surface of a particularly polar resin solution. There is incompatibility and no wetting. If a suitable surfactant can be found with an aliphatic tail attracted to the particle surface and a polar portion attracted to the resin molecules, chemical contact from particle to paint will be established, interfacial tension will drop and cissing will not occur. The surfactant provides a bridge across the gap between the two unlike molecules. [Pg.132]

Cissing is the appearance of small, saucer-like depressions in the film s surface. These are caused by particles or droplets of incompatible material, which either land on the film during drying, or are present in the paint itself. The weight of the particle causes it to sink but, since there is no attraction between paint molecules and molecules in the particle s surface, the surface tension of the paint resists the particle s entry into the liquid film. Immediately under the particle, the paint molecules have no alternative but to be in close proximity to the particle. In the zone surrounding the particle, the liquid skin is depressed by the particle s weight, but attractions from within the paint film pull the surface molecules away from the particle. There is said to be a high interfacial tension between paint and particle. The net result, as Fig. 10.4 shows, is a ciss mark... [Pg.144]

Drying of the paints by modifying the interfacial tension, and ensuring that the painted surface remains unaffected by the adverse effects of water... [Pg.445]

Interfacial tension measurement, both static and dynamic, provide clues about the usefulness of the surfactant as an emulsifier for a given system of oil and water. Not only is the sharp decrease in interfacial tension desirable, but it is also important to produce the minimum tension possible from a given surfactant. In fact the results of interfacial tension measurements can provide information about the effectiveness and efficiency of surfactants for a given system. A sharp decrease in interfacial tension with the increase in concentration of surfactant indicates that the surfactant is effective, whereas one that causes minimum interfacial tension although not with a sharp rate would be considered efficient. Depending on the requirements, one can use the effective or the efficient surfactant for a given formulation of paints, inks, and polishes. Interfacial data of surfactants can be used as the main criteria for quality by the users of surfactants. [Pg.453]

The film formation process is extremely complex, and there are a number of theories — or more accurately, schools of theories — to describe it. A major point of difference among them is the driving force for particle deformation surface tension of the polymer particles. Van der Waals attraction, polymer-water interfacial tension, capillary pressure at the air-water interface, or combinations of the above. These models of the mechanism of latex film formation are necessary in order to improve existing waterborne paints and to design the next generation. To improve the rate of film fonnation, for example, it is important to know if the main driving force for coalescence is located at the interface between polymer and water, between water and air, or between polymer particles. This location determines which surface tension or surface energies should be optimized. [Pg.58]

Interfacial tension of solid-liquid and solid-solid interfaces Yes (many methods, e.g. Fowkes, Hansen, van Oss-Good) Wetting, adhesion, characterization and modification of surfaces... (paints, glues...)... [Pg.8]

Equation 4.2 gives the theoretical work of adhesion for ideal interfaces and due only to surface phenomena. Adhesion is a much more complex phenomenon with many applications (e.g. paints, polymer technology and cleaning via surfactant-based formulations). We discuss wetting and adhesion in Chapter 6. Example 4.1 shows how the ideal work of adhesion can be estimated from theories for interfacial tension. [Pg.76]

Cola WetDOSS70PG interfacial tension reducer, mining Cola WetDOSS70PG interfacial tension reducer, paints/ coatings BYK -347... [Pg.2738]


See other pages where Paints interfacial tension is mentioned: [Pg.276]    [Pg.564]    [Pg.113]    [Pg.46]    [Pg.827]    [Pg.311]    [Pg.827]    [Pg.161]    [Pg.217]    [Pg.131]    [Pg.3145]    [Pg.564]    [Pg.310]    [Pg.83]    [Pg.16]    [Pg.1140]    [Pg.384]    [Pg.1955]    [Pg.1]    [Pg.251]    [Pg.157]    [Pg.403]    [Pg.296]    [Pg.382]    [Pg.121]    [Pg.121]    [Pg.130]    [Pg.375]    [Pg.51]    [Pg.53]   
See also in sourсe #XX -- [ Pg.335 ]




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Interfacial tension

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