Styrene-acrylate emulsion (styrene-acrylate emulsion) i […]
Styrene-acrylate emulsion (styrene-acrylate emulsion) is obtained by emulsion copolymerization of styrene and acrylate monomers. Its water resistance, alkali resistance, good scrub resistance, and resistance to outdoor aging are widely used in adhesives, coatings and other fields.
Milky white liquid with blue light. The solid content is 40 to 50%, the viscosity is 80 to 2000 mPa·s, the residual monomer content is 0.5%, and the PH value is 8 to 9. The styrene-acrylic emulsion has good adhesion, transparent film, good resistance to water, oil, heat and aging.
The styrene-acrylic emulsion is used as a paper product adhesive and can also be used in combination with starch, polyvinyl alcohol, sodium carboxymethyl cellulose and other adhesives. Store in a warehouse at 5 to 30 °C for a period of 1 year.
The monomer is dispersed in an emulsion state in water by an emulsifier and is referred to as an emulsion polymerization. The conventional emulsion polymerization system consists of four parts: monomer, water, water-soluble initiator, and water-soluble emulsifier. The formula used in industry is much more complex. Emulsion polymerization is often a copolymerization. In addition to the main monomer, there may be second and third monomers.
The advantages of emulsion polymerization:
(1) Water as medium, cheap and safe. Latex viscosity is low, conducive to stirring heat transfer, transportation and continuous production;
(2) The polymerization rate is fast, while the product has a high molecular weight, and the polymerization can be performed at a lower temperature;
(3) It is beneficial to the direct use of latex and the production of environmentally friendly products such as water paints, adhesives, paper, leather, and fabric treatment agents.
Disadvantages of emulsion polymerization:
(1) When a solid product is needed, the emulsion needs to be condensed, washed, dehydrated, dried, etc., and the cost is high;
(2) Impurities such as emulsifiers are left in the product, and it is difficult to completely remove the net and damage the electrical properties.