Acrylic emulsion, is intended specifically for the production of water-based building paints. This emulsion has a relatively high viscosity, as a result of which thickeners used in the production of other emulsion paints, the formulations of which are given in Ch. This simplifies the production of paints and increases their stability during storage in containers, since the viscosity of thickeners changes during storage. It is completely resistant to the action of hard water and water-soluble salts present in some pigments. This is the second advantage of this acrylic emulsion Malaysia in the production of paints, since it allows you to safely use ordinary water both in their manufacture and for their subsequent dilution during use, if necessary. Since the pH of the paint is adjusted with ammonia to about 9 4 before packaging, only alkali-resistant pigments should be used in its manufacture.
An acrylic emulsion of grade A, which is a dispersion of low molecular weight polymethyl acrylate, is obtained by slowly adding an emulsion of methyl acrylate in a solution of C-10 emulsifier to an aqueous solution of an initiator over 1 5 – 2 hours. Ammonium persulfate is used as an initiator.
Thixotropic paints are created on the basis of acrylic emulsions. In 1965, lateques were obtained, from which it is possible to make water-based acrylic semi-gloss paints for interior work, which have better technological properties than semi-gloss oil paints. They also have good flow and good adhesion to old alkyd coatings. The films obtained are characterized by their hardness, resistance to water and detergents.
The industrial production of acrylic emulsions is poorly developed due to the high cost of monomeric esters of acrylic acid. The direct synthesis of acrylates from acetylene, carried out in the Federal Republic of Germany, helped to reduce the cost of the starting monomers. It is possible that the oxidation of propylene to acrolein and acrylic acid or other petrochemical syntheses will be more economical.
Colorful films based on acrylic emulsions are distinguished by their beautiful appearance, increased resistance to dry and wet friction, high water resistance, good adhesion of films to the skin, high elasticity and aging resistance. The disadvantage of these films is their thermo plasticity, relatively fast softening with increasing temperature. In addition, the films are not resistant to the action of a number of organic solvents and are not frost-resistant enough. The latter disadvantage, however, is eliminated by the introduction of plasticizers.
Recently, copolymer acrylic emulsions, especially those containing various functional groups, are widely used. It has been shown that the introduction of functional groups into linear alkyl acrylate molecules improves the film-forming properties of latexes, and it becomes possible to obtain films of a three-dimensional structure. For more articles like this one, click here.