Titanium dioxide latex-pigment dispersions

Apart from latexes, S-FFF has been used to fractionate and determine the size distribution of numerous industrial colloids including water-based titanium dioxide dispersions [6,171], carbon black dispersions [6],phthalocyanineblue [6], various silica sols [141,171,176], gold and silver sols [385], pigments, metal and ceramic particles, clay and a host of latexes [294]. Gold, palladium, silver and copper particles in the size range 0.3-15 pm were separated by steric-S-FFF and their size distributions determined in less than 12 min [69]. 

Figure 17. Low-shear-rate (2 s ) viscosity Pa s) dependence on latex surface acid meqlm, latices were equilibrated at pH 9 before the titration), for the latices noted in Figure 14 in 0.32 volume fraction dispersions containing titanium dioxide at a pigment to pigment plus latex volume ratio of 0.21). All dispersions were thickened at 1.1 wt % thickeners in the aqueous phase.

The use of water in place of organic solvents as a paint thinner has obvious attractions. The first important commercial product of this type was the oil-bound water paint, the vehicle being an emulsion of oil or varnish in an aqueous solution of gelatine. The preferred white pigment was lithopone (zinc sulphide/ barium sulphate), and a high ratio of pigment to binder was used. This product was eventually replaced by the emulsion paint (known as latex paint in USA and dispersion paint on the continent of Europe). It used a synthetic vinyl polymer as a binder, mainly a co-polymer of vinyl acetate with either vinyl versatate or butyl acrylate, with titanium dioxide as the white pigment. Attempts to use an alkyd emulsion based on oil as the vehicle were commercially unsuccessful. The droplet size of the dispersion at emulsion is normally about 0.2-1 //m. 

Uses Dispersant emulsifier, stabilizer for latex emulsions, paints, titanium dioxide and extender pigments color enhancer, compatibilizer in paints/coatings Features High tolerance for multivalent cations... 

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