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BYK Additives Product Groups & Wetting and dispersing additives for stabilizing pigments and extenders in liquid media. The wetting of the solid particles is promoted and uncontrolled fl occulation is suppressed. The good defl occulation of the solid particles improves gloss and leveling and prevents fl ooding in pigment mixtures. The viscosity is reduced and larger quantities of pigments and extenders can be worked in. Controlled fl occulating additives are also available for application in primers and extenders, to prevent sagging and settling. Surface additives to prevent surface defects and improve surface properties such as slip, leveling, or substrate wetting. Products based on modifi ed polysiloxanes primarily reduce the surface tension and are therefore used as substrate wetters and anti-crater additives. Modifi ed polyacrylates are used to improve leveling. Some of these additives also exhibit defoaming properties as well. For special applications, reactive additives are also available. Scratch resistance can be improved with Al2O3 and SiO2-based nanoparticles, which are present as dispersions in a liquid carrier medium. Defoamers and air release agents suppress foam formation which is almost always attributable to the incorporation of air with stirring and mixing processes or with the application of the material. Any foam bubbles that develop are transported to the surface and destabilized, and as a result they quickly burst and do not cause any defects. Rheological additives increase the viscosity of liquid media and control the fl ow (pseudoplastic, thixotropic). Sedimentation of solid particles is greatly reduced, and sagging on inclined surfaces is minimized. Furthermore, it is possible to optimize the orientation of effect pigments and, with it, the effect formation. Adhesion promoters are used to increase the adhesion between individual coating layers or the adhesion of a single coating on a (metallic) substrate. Wax additives are available as micronized waxes in powder form or as emulsions and dispersions of wax particles in liquid carrier media. Depending on the types of wax used (what is important are melting point and polarity), the additives will increase or decrease surface slip, improve scratch and abrasion resistance, and increase hydrophobicity. Depending on the size of the wax particles, the additives will reduce gloss and can be used for matting to create structure/texture, and to adjust the haptic properties of surfaces. Special types can also be used to adjust the rheology. UV absorbersbased on nanoscale inorganic particles (ZnO and CeO2) preserve coatings from degradation due to high-energy UV radiation and also protect sensitive substrates, such as wood. Viscosity depressants are used to lower viscosity in fi lled PVC plastisols. They permit the use of higher fi ller volumes with the same viscosity and reduction in the plasticizer content. Processing additives serve to optimize the processing properties of synthetic materials, especially with compounding and extruding. With powder coatings, the pigment and fi ller uptake is improved and, consequently, extrusion is also made easier. SCONA® plastic modifi ers SCONA® is the brand name of a family of chemically modifi ed polymers produced using a patented process which grafts reactive monomers to free-fl owing substrate polymers. The radical grafting in the solid phase following the substrate-phase polymerization process makes it possible to carry out targeted modifi cations on saturated polymers. Graft density, graft chain length, graft chain structure and the degree of cross-linkage can be adjusted with excellent reproducibility by selecting monomer and activation ratios over a wide range. Specifi cally matched modifi ers are available for the different applications and materials. 4


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