A defoamer, also known as an antifoam agent or a foam inhibitor, is a chemical that reduces the surface tension of a liquid and destroys bubbles and foams in the liquid. Defoamer is commonly used in various industrial and production processes, such as chemical, pharmaceutical, paint, food and other fields. Its main function is to prevent bubbles and foams from gathering on the liquid surface and reduce the influence of liquid surface tension on the production process.

The following are some of the properties that defoamer may need to test, detailed in the following table:

We reminds you: The specific performance that needs to be tested should be determined according to the field of use and application requirements of defoamer.

What properties should be tested for defoamer? How to detect?

Detection method
Defoaming property

Defoaming performance is usually assessed by observing the stability and defoaming speed of the foam. In the specific operation, a certain amount of defoamer is added to a certain amount of liquid, and then the stability and defoamer speed of the foam are observed within a certain period of time. The faster the defoaming speed and the more unstable the foam, the better the defoaming performance of the defoaming agent.

Dispersion property

The dispersion property of defoamer can be measured by centrifugal method, filtration method, etc. Centrifugal method is to add the defoamer to the water, and then use the centrifuge to centrifuge the mixed liquid, according to the relative density of the liquid is different, the liquid is divided into different levels, according to the distribution of the defoamer in different levels to evaluate its dispersion performance. The filtration rule is to add the defoamer to the water, and then filter it with a filter, and evaluate the dispersion performance of the defoamer according to the filtration speed and filtration residue.

solubility

The solubility of defoamer can be evaluated by adding a certain amount of defoamer to a certain amount of solvent at different temperatures, and then oscillating or stirring for a certain time to determine the weight or concentration of the remaining undissolved defoamer.

Surface activity energy

The effect of defoamer on the surface tension of water is usually assessed by measuring the extent to which the surface tension is reduced. The surface tension can be measured by dynamic and static methods, the dynamic method is usually measured using an interfacial tension meter or the ring method, and the static method is measured using the equilibrium method or the bubble pressure method.

What properties should be tested for defoamer? How to detect?

stability

Stability testing is done by testing the stability of the defoamer under different environmental conditions. For example, the stability of the defoamer can be tested under different conditions such as temperature, PH and water hardness. Stability tests can be evaluated by looking at the appearance, measuring PH, viscosity, surface tension and other indicators.

durability

Durability tests can be evaluated by measuring changes in the properties of the defoamer after prolonged use or storage. For example, the defoamer’s defoaming performance, surface tension, PH value and other indicators can be measured at different time periods or different temperatures to assess its durability.

Toxicity

The toxicity of defoamer usually includes acute toxicity and chronic toxicity. Acute toxicity tests can be performed by animal experiments or cell culture methods to assess the acute toxicity of antifoaming agents to organisms. Chronic toxicity testing usually requires long-term exposure or long-term consumption to assess the chronic toxicity of the antifoaming agent to organisms.

Other properties

In addition to the above properties, the defoamer may also need to be tested for other properties, such as antistatic, high temperature resistance, etc. The detection method can be selected according to the specific requirements, such as the use of electrometers or high temperature thermostatic tanks and other equipment for determination.

In short, testing the performance of defoamer needs to select the corresponding test method according to the specific performance. The selection of detection methods and the control of experimental conditions are of great importance to the accuracy and repeatability of test results.