APE-free solution for high-gloss water-based alkyd enamels
n paints, mainly water-based ones, systems are very complex with several components, which, under normal conditions, would not form a homogeneous solution. That is why surfactants are essential for the formulation of paints. They stabilize the system and aid in several properties and application features of the paint. They are essential for the emulsion polymerization process and, in the final paint, during the pigments and fillers dispersion process. In both processes, they act as system stabilizers.
Alkyd resins are widely used to formulate solvent-based enamels for wood and metal paint. The success of alkyd resin systems results from their relatively low cost, versatility, and user-friendliness. However, due to health and environmental issues, there is a growing interest in developing water-based alkyd enamels.
The OXIMULSION® 9000 emulsifiers line enables the production of water-based alkyd enamels with the same properties in the final application as the traditional solvent-based formulations since the alkyd resin backbone is preserved.
The solution is designed to enable easy emulsification of long-in-oil alkyd resins, using conventional mixing equipment with low shear and low emulsifier content through the phase inversion technique.
The emulsification of alkyd resins through the phase inversion method is performed right after the alkyd polymerization. The resin is cooled at a working temperature – below 100°C – neutralized and then the OXIMULSION® 9000 emulsifiers (anionic surfactant: OXIMULSION® 9800 and non-ionic surfactant: OXIMULSION® 9900) are added and homogenized in the medium. The slow addition of water at the same temperature as the resin is performed until the water’s volumetric fraction reaches a critical point where the phase inversion occurs (from water-in-oil emulsion to oil-in-water).
Using conventional low shear equipment during the emulsification process, the OXIMULSION® 9000 emulsifiers create emulsions with a small particle size (around 200 nm) and stable for up to 2 years.
Using about 4% OXIMULSION® 9000, it is easy to create an oil-in-water emulsion of a long-in-oil alkyd resin with solids content between 50 – 60% by weight. By optimizing the temperature, dosage and composition ration of anionic and non-ionic surfactant, it is possible to achieve a solids content of up to 72% by weight.
Why choose the OXIMULSION® 9000 emulsifiers?
- Alkyd enamels with low VOC content, low odor, and a low risk to health and the environment;
- Elimination of solvents (cost reduction, no emissions in the workplace);
- No necessary investment in process and low energy demand;
- A flexible process that generates emulsions with a high solids content.
