At Concentrol we work day after day to devise and develop the best solutions for our clients. The research processes carried out in our laboratories are essential to verify the efficacy and safety of our product lines. In this article we are going to analyze how Concentrol’s mineral oil-based antifoaming agents are and work; and what performance is offered by EMULTROL DFM OLM-17, one of the star products of the antifoaming agent range.

 

Foam is a dispersion of gas in a liquid, which is formed by the presence of surfactants in the medium. In our day to day we are used to using products that make foam such as shampoos or detergents, among others. Industrially, however, the generation of foam is not always desirable, since it can cause a decrease in production performance and a decrease in the quality of finished products.

In the decorative paint industry, excess foam can lead to increased production time, cause problems during packaging, and cause surface defects in the final appearance of the coating.

Therefore, it is essential to use an antifoaming agent that affords optimal control of foam formation during production stages and that maintains its properties during storage. In this way, paints with a smooth finish free of craters or fish eyes can be obtained.

The selection of an appropriate antifoaming agent for each formulation is essential to guarantee the quality of the paint manufactured. For this reason, the behaviour of this type of additives must be studied in detail by means of tests that make it possible to predict antifoaming effectiveness, persistence and possible incompatibilities.

Concentrol has a team of experts with extensive experience in the design and selection of suitable antifoaming agents for each application. To offer its customers the best solution at all times, Concentrol has developed the EMULTROL DFM OLM antifoaming agent range. These products have been specifically formulated to achieve a persistent antifoaming effect with the best cost-effectiveness.

One of the most outstanding products in the range of antifoaming agents designed by Concentrol is EMULTROL DFM OLM-17, which is specially designed for foam control in decorative paints.

STUDY METHODOLOGY

For the evaluation of the properties of this antifoaming agent in Concentrol’s laboratories, efficacy, stability and compatibility tests have been carried out, using four polymeric dispersions of acrylic, styrene-acrylic, vinyl-acrylic and vinyl-VeoVa as a medium.

To determine the antifoaming efficacy, a 200 ml sample of polymeric dispersion is taken, 0.2% of EMULTROL DFM OLM-17 is added and it is subjected to a stirring process at 1300 rpm for 5 minutes. The percentage of air entrained in the mixture is calculated, from the initial and final density differences.

Another parameter to take into consideration is the stability that the antifoaming agent presents in the formulation over time. For its study, a sample of polymer dispersion with 0.2% antifoaming agent is taken and stored at 45ºC for one week. Subsequently, the antifoaming effectiveness test is repeated.

     1 / AGITATION PROCESS 2 / CALCULATION OF DENSITY

Finally, it must be ensured that the antifoaming agent under study does not present problems of compatibility with the formulations, which would cause adverse effects on the coating of the paint such as fish eyes, craters or orange peel. For this purpose, a 120 µm thick layer applied on a glass plate is visually evaluated.

RESULTS IN THE AGING TEST OF THE EMULTROL OLM-17 ANTIFOAMING AGENT FOR DECORATIVE PAINTS

 

The technical team of Concentrol laboratories has carried out compatibility and efficacy tests over time of the EMULTROL DFM OLM-17 antifoaming agent in polymer dispersions common in the decorative paint sector, such as acrylic, styrene-acrylic, vinyl-acrylic dispersions and vinyl-VeoVa. Presenting good effectiveness over time in the four polymers studied, as well as good compatibility since it does not show any type of irregularity or defect on the final coating.

In the last laboratory study, new tests were carried out to complete the research and obtain detailed information on the stability of the antifoaming agent in decorative paints.

First, the stability over time of the antifoaming efficacy of EMULTROL OLM-17 was analyzed. For its study, a paint sample with 0.2% antifoaming agent was taken and stored at 45 °C for a week. Subsequently, the antifoaming effectiveness test was repeated by stirring the mixture at 1,300 rpm for 5 minutes and the percentage of entrapped air was calculated.

The test was carried out on acrylic and vinyl-VeoVa decorative paints, which are the most used.

Graph 1- Results of the antifoam test of EMULTROL DFM OLM-17 in different decorative paints.

The results obtained showed that EMULTROL DFM OLM-17 has good antifoaming effectiveness in the paints under study, which remains stable over time.

Furthermore, as has already been extensively described in previous studies, this product does not present problems of compatibility with paints.

Therefore EMULTROL DFM OLM-17 is a cost-effective antifoaming agent that is suitable for the production of a wide variety of decorative paints, especially those based on acrylic and vinyl-VeoVa.