Foam is a dispersion of gas bubbles in a liquid, which is formed by the presence of surfactants in the medium. In our everyday life we are accustomed to using products that foam up, such as shampoos or detergents, among others. Industrially, however, foaming is not always desirable, as it can cause a decrease in production yield and obtaining poor-quality finished products.
In the decorative paint industry, excess foam may cause an increase in production time, cause problems during the packing and cause deficiencies in the final appearance of the coating. Thus, it is essential to use an antifoaming agent that allows optimal control of foam formation during production stages and keeps its properties during storage. Thus, paint with a smooth finish and free of craters and fisheyes can be obtained.
Choosing the appropriate defoamer for each formulation is imperative to ensure the quality of the paint. For this reason, it is necessary to study in detail the behavior of such additives by means of tests that allow us to predict their defoaming effectiveness, persistence and potential incompatibilities.
Concentrol has a team of experts with extensive experience in the design and selection of defoamers that are suitable for every application. In order to offer its customers the best solution in every case, Concentrol developed a range of antifoaming agents called EMULTROL DFM OLM. These products have been specifically formulated to achieve a persistent defoaming effect with the best cost-effectiveness.
One of the flagship products in the range of defoamers designed by Concentrol is EMULTROL DFM OLM-17, which is particularly suitable for controlling foam in decorative paints.
STUDY METHODOLOGY
For the evaluation of the properties of this defoamer at Concentrol laboratories we conducted tests of efficiency, stability and compatibility, using four kinds of polymer dispersions as a medium: acrylic, styrene-acrylic, vinyl-acrylic and vinyl-veova, which are the main bases for most decorative paints currently used.
To determine the defoaming effectiveness, a sample of 200 ml of polymer dispersion is taken, 0.2% of EMULTROL DFM OLM-17 is added and then it undergoes a process of agitation at 1300 rpm for 5 minutes. Afterwards the percentage of air in the mixture is calculated by measuring changes in its density.
Another parameter to take into consideration is the formulation stability that a defoamer presents over time. For its study, a sample of polymer dispersion with 0.2% of defoamer is taken and stored at 45 °C for one week. Subsequently, the defoaming effectiveness test is repeated.
Finally, we make sure that the tested defoamer does not present problems of compatibility with formulations, which would cause adverse effects on the paint coating such as fisheyes, craters or orange peel. To this end, a layer 120 microns thick applied on a glass plate is visually assessed.
RESULTS OF EFFECTIVENESS AND AGING OF THE DEFOAMER DFM EMULTROL OLM-17
The results show that EMULTROL DFM OLM-17 has a good defoaming effectiveness in the four polymers studied, which remains virtually unchanged over time. In addition, we note that this product does not cause any irregularity or defect in the final coating of the aforementioned polymers.
Therefore, we can conclude that EMULTROL DFM OLM-17 is a cost-effective defoamer that is suitable for the production of a wide variety of decorative paints, especially those based on polymeric dispersions such as acrylic, styrene-acrylic , vinyl-acrylic and vinyl-veova.
Figure 1. Test results of the defoamer EMULTROL DFM OLM-17 in various polymer dispersions
Figure 2. Test results of the defoamer EMULTROL DFM OLM-17 in various polymer dispersions after the aging stage
Figure 3. Compatibility test results of the defoamer EMULTROL DFM OLM-17 in polymer dispersion applied on a glass plate.
EMULTROL DFM OLM-17
● Formulated from high quality mineral oils
● It does not contain Ethoxylated alkylphenols.
● Easy to handle
● Stability during storage: no phase separation is observed.
● Excellent cost-effectiveness
● Excellent defoaming efficiency
● Good long-term performance
● Appropriate compatibility: does not cause adverse effects on the paint such as orange peel, fisheyes, craters or wetting defects.
● Excellent foam reduction in paints based on polymer dispersions of acrylic, styrene-acrylic, vinyl-acrylic and vinyl-veova types.
Keep in mind that every formulation is unique and may require the use of specific defoamers to ensure optimal results. For this reason, Concentrol offers its customers the possibility of customized studies in order to respond to their specific needs.
