Polymer aqueous dispersions and relevant additives

Additives

• “ChimAcryl XD-135” dispersant for water-borne paintwork materials
• “ChimAcryl XP-342” defoamer
• “ChimAcryl XZ-223” thickener for aqueous dispersion paints
  

Dispersions for production of water-soluble paintwork materials

• “Chimplast-Acryl-001” styrene – acrylic dispersion
  
• “Chimplast-Acryl-001B” styrene – acrylic dispersion
  
• “Chimplast-Acryl-100” styrene – acrylic dispersion

Specialty dispersions

• “Chimplast-Acryl-003” acrylic dispersion
• “Chimplast-Acryl-011” styrene – acrylic dispersion
•  “Chimplast-Acryl-012” acrylic dispersion
  
• “Chimplast-Acryl-012B” styrene – acrylic dispersion
• MKF-50, MKF-70 melamine-urea-formaldehyde resins

 Polymer aqueous dispersions and relevant additives. Description.

   Various type polymer dispersions are used as film formers in water-based paintwork materials. Polymer dispersions are bluish cloudy or milky liquids of low viscosity. These systems are mainly composed of nearly spherical polymer particles uniformly distributed in water phase. The most important of them are vinyl acetate copolymers with dibutyl maleate, vinyl acrylates; vinyl propionates (normally as copolymers with acrylates), pure polyacrylates and polymethyl methacrylates, acrylic copolymers with styrene, and styrene butadienes. 

   Distinctive properties of these main copolymer dispersions are: content of non-volatiles, viscosity, pH, mean particle size, residual monomer and minimum glass transition temperature.

   Depending on glass transition temperature and UV- or alkali  resistance, polymer dispersions are used in paintwork materials for all type substrates both mineral and metal, paper, wood, and even plastics for coatings indoors and outdoors. In terms of production output paint work materials for external and internal walls, synthetic polymer-base plasters, and latex paints seem to be the most important of them. Application of these materials does not require any special safety measures. Most polymer dispersions naturally dry at temperatures above 5єC.

   As polymer dispersions do not stabilize pigments and fillers, it is necessary to use wetting and dispersing agents in water-based paintwork materials. However, these agents should not be used in excessive amounts as they impair water resistance of the coating.

   Presence of surfactants which stabilize polymer dispersions makes them liable to foam formation, so it is normally required to introduce defoamers which should be added directly into the pigment paste in presence of wetting agents. To make film forming more efficient it is often recommended to introduce coalescing additives as well.

    Most dispersions have too low viscosity for application, hence their rheological characteristics should be corrected by introduction of thickeners. For this purpose, besides conventional cellulose derivatives, various synthetic products and inorganic substances are used. Dispersions which contain the finest polymer particles dispersed in water are nutrient medium for microorganisms.  For this reason they should be protected from microbe attack in the packaging with packaging preservatives – biocides. The coatings are also attacked in wet environment and they should be treated with suitable antimicrobial agents.