Acrylic powder coating properties

Siloxane containing polyester, poly(alkylene oxide) and polystyrene type copolymers have been used to improve the heat resistance, lubricity and flow properties of epoxy resin powder coatings 43). Thermally stable polyester-polysiloxane segmented copolymers have been shown to improve the flow, antifriction properties and scratch resistance of acrylic based auto repair lacquers 408). Organohydroxy-terminated siloxanes are also effective internal mold release agents in polyurethane reaction injection molding processes 409). 

Certain components of domestic appliances are also coated with electrodeposition paints. Two-pack polyurethanes are applied if the dimensions of the parts are too large for the electrodeposition bath. These paints dry at ambient temperature to give films with similar properties to stoving acrylic enamels. Solvent-free powder coatings are also used to coat domestic appliances. Nowadays powder coatings and precoated metal (coil coating) are gaining more importance. 

Chem. Descrip. Ethylene/magnesium acrylate copolymer Uses Flatting agent that reduces gloss in polyester powder coatings Features Low m.w. ionomer Properties Gran. vise. 7,000 cps (190 C) m.p. 95 C AClyn 285 [Honeywell Spec. Chems.]... 

DR pigments are used in paint applications where their properties are required, such as high-temperature paints and coil-coating paint systems based on fluoropoly-mers, silicone-polyester, and plastisol. The NiSbTi and CrSbTi DR pigments are used in trade sale paints including acrylic house paints, general industrial paints in polyester systems, and fleet colors in thermoset acrylic, thermoplastic acrylic, and polyurethane systems. They are also used in polyester-based powder coating applications. 

Table 5.1 outlines useful properties, products and application areas of acrylic systems. Key market segments are coatings based on methacrylates as well as emulsions and water-based sealants. Acrylic emulsions and redispersible powders as cement modifiers offer many useful products for several end-uses. However, the high cost of acrylic has limited their use as cement modifiers. The use of water-based acrylic systems is increasing because of their non-toxic and environmentally friendly nature. 

Chem. Descrip. Micronized polyethylene wax/acrylic resin aq. disp. Uses Rub resist, aid, abrasion resist, aid, antiblocking agent, slip agent in aq. printing inks, stains, coatings, and paints Properties Fineness (Hegman) 5.5-6.0 dens. 1.02 0.04 g/cc vise. 5000 500 cps pH 8.5 0.5 35.0 0.4% total solids 25% wax solids, 10% acrylic resin solids Use Level 1.0-3.0% wt. of total formula Microspersion 250-50 [Micro Powders]... 

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