Water borne polymer paint coatings

A nonchromated, water-borne primer applied to [2B] alloy samples, with the appropriate surface preparation and plasma deposition of an ultrathin plasma polymer, was also compared to controls prepared by depositing a chromated primer on chromate conversion-coated A1 substrate. The same comparison was also performed for IVD Al-coated 2024-T6 substrates (pure aluminum is deposited by ion vapor deposition process on aluminum alloy 2024-T6). In the latter case, the primer could not be removed from the IVD Al-coated panels that were treated with the plasma polymer prior to spray primer application. It is interpreted that the water-borne spray paint penetrates into the column structure of the top surface of the IVD Al-coated substrates when the surface energy was modified by the application of a plasma polymer. This effect could be viewed as interactive coating with a porous surface. 

Coatings formulations based on water borne polymers usually depend on specific ingredients for rheological profile adjustment and overall properties optimization. There is a large variety of additives which can be used to modify the rheology of a system. Natural organic derivatives (e.g. cellulose ethers) have been traditionally used in the paint industry and are well established. Synthetic thickeners, on the other hand, have appeared later but quickly became very popular, mostly because of their ease of use (liquid versus solid)... 

The water-soluble EHEC is used in water-borne paints, pastes, polymer dispersions, ceramics and cosmetics, and pharmaceuticals,whereas organic soluble EHEC is used in inks, lacquers, and as coatings. 

Plasma treatment of Parylene C films has proved to be very effective in improving the painting properties of Parylene C polymers with respect to a solvent-borne primer as described above. The similar effect of LPCAT plasma treatment on the adhesion of Parylene C polymer to water-borne primer (44-GN-36, Deft Corp.) was also observed. Table 30.3 summarizes the tape test results for the Deft primer coatings on Parylene C surfaces treated by LPCAT under different plasma conditions. 

Since the 1970s polymer dispersions manufactured by emulsion polymerization have increasingly substituted solvent-borne paints, coatings, adhesives and inks. Water-based emulsion systems have made a significant contribution to VOC-reduction in corresponding industries. The emulsifier in... 

The blending of resins is a simple and useful technique for improving paint properties. While water-borne acrylic resins and polyurethanes have been widely used as polymers for automotive coatings, both water-borne resins are inferior to corresponding solvent based counterparts because of hydrophilic functional groups or surfactants which are introduced to impart dispersion stability to these resins. Table 7-6 shows some of the advantages and disadvantages of polyurethane and acryhc resins. 

A special kind of microgel is the core-shell particle (Fig. 10.3). Here a lightly crosslinked polymer core is contained inside an uncrosslinked outer shell, grown or grafted onto it. The outer shell polymer would be soluble in the liquid medium were it not attached to the inner core. Some coreshell microgels are made to function as thickeners in solvent-borne paints, while others are designed for water-based coatings and function in aqueous media in both cases the structure of the particles is essentially the same. That is, the shell is solvated by the continuous phase, whether it is hydrocarbon or water. 

Most of the important types of modem solvent-borne coatings — epoxies, alkyds, acrylics — are also available in waterborne formulations. In recent years, even urethane polymer technology has been adapted for use in waterborne coatings [1]. However, waterborne paints are not simply solvent-borne paints in which the organic solvent has been replaced with water the paint chemist must design an entirely new system from the ground up. In this chapter, we discuss how waterborne paints differ from their solvent-bome counterparts. 

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