Defoamers are widely used in water treatment, coatings, textile printing and dyeing, papermaking and other industries. Defoamers are essential additives in the production process, which can eliminate harmful foams, accelerate production efficiency, and prevent foam from affecting product quality. Make an impact. This article analyzes the cause of foaming and the role of the main component of the defoaming solution-defoaming agent.
(Picture: Application of defoamer in emulsion)
Cause analysis of blistering
In the industrial production process, a large number of additives are used and some production processes are also prone to cause foam. Foam is a dispersion system in which gas is dispersed in liquid. The volume occupied by the liquid is very small, and the volume occupied by the foam is very large. The gas is separated by a continuous liquid film to form bubbles of varying sizes with a large gas-liquid surface.
Foam is an unstable system, but usually the foaming system contains surface active substances or foaming substances, which will cause the surface tension of the foam system to change, resulting in easy and stable foam. For example, in the paint production process, in addition to film-forming substances, pigments, solvents and other ingredients, it is usually necessary to add dispersants, emulsifiers, thickeners and fungicides for preparation. Many of these additives are surface active substances. It is easy to produce foam in the high-speed stirring process, and the foam is not eliminated in time, which easily affects the film forming property of the coating film and causes film forming defects. The common solution is to add defoamer to defoam and suppress foam. Antifoaming agents generally have low surface tension, so they can spread on the surface of the foam system, so that the surface viscosity of the foam decreases, and the drainage increases rapidly, defoaming foam.
(Picture: Analysis of the cause of blistering)
Five major components of defoamer help defoam
The defoamer is not composed of one substance, but contains multiple components, ranging from 2 to 3 kinds, and as many as 5 or more. They are divided into 5 categories according to their basic functions: main carrier, anti-foaming agent, auxiliary anti-foaming agent, Stabilizer or compounding agent, emulsifier or spreading agent, etc. The main components are as follows:
1. Carrier
The carrier plays a role in supporting the main anti-foaming agent and auxiliary anti-foaming agent, and facilitates their incorporation into the foaming system. Carriers occupies most of the formula of Xiaohuai agents. They are usually hydrocarbon oils or water, and sometimes other substances such as fatty alcohols, fatty acid esters or solvents are also used. In addition, the carrier also promotes the performance of the defoamer.
2. Anti-foaming agent
The main anti-foaming agent is the main active ingredient in the anti-foaming agent, usually insoluble particulate matter, such as hydrophobic silica (treated with silicone oil), fatty amine, paraffin, fatty acid and fatty acid ester.
The main anti-foaming agent is neither soluble in the carrier nor in the foaming medium. Sometimes, some anti-foaming agents dissolve in the foaming medium at low temperatures, and when the temperature rises, they will precipitate out of the solution, such as polyoxy-Zene-polyoxypropylene block copolymers. The main anti-foaming agent is the most important formula in the defoaming agent, and sometimes its content in the mixed ingredients of the anti-foaming agent is not the most.
3. Auxiliary anti-foaming agent
Auxiliary anti-foaming agent is an active component that plays a regulatory role and can have a synergistic effect on anti-foaming agent. The addition of auxiliary anti-foaming agent can adjust the solubility, crystallinity and spreading effect of the main anti-foaming agent in the carrier or in the foaming medium, and improve the surface effect of the main anti-foaming agent. Auxiliary anti-foaming agents are fatty alcohols, fatty acid esters, polysiloxanes and certain non-oil-soluble polymers.
(Picture: Composition of defoamer)
4. Stabilizer or compounding agent
Stabilizers and compounding agents are additives that improve the stability of defoamers. They are usually commercial antifoaming agents, auxiliary antifoaming agents and cosolvents for carriers. In water-based defoamers, the stabilizer can be a preservative to prevent the product from being destroyed by bacteria during storage.
5. Emulsifier or expander
The main active component of the defoamer is immiscible with the foaming medium, but during the defoaming process, it must be quickly emulsified and dispersed into the foaming system or spread on the foam surface.
Therefore, an emulsifier or spreader must be added to the defoamer. They are blended with the main antifoaming agent, auxiliary antifoaming agent, carrier and other main ingredients, and added to the foaming system together, so that the main ingredients of the defoaming agent are immediately dispersed in the foaming medium, helping the defoaming agent to be faster and more efficient. Contact the surface more to improve the spreading efficiency of the defoamer.
Commonly used emulsifiers or spreaders are esters, ethoxylated products, sorbitan carboxylates, non-ionic silicone surfactants and alcohol sulfate esters.
(Picture: Formula of defoamer)
The industrial grade defoamer sold by Nanhui defoamer manufacturer has high foam breaking rate and ideal effect. It can be customized according to the customer's application environment and the performance requirements of the defoamer, and the formula can be adjusted to make the defoamer suitable for defoaming in various environments.
Nanhui is a manufacturer with years of application experience. It has far more defoaming technology than other antifoaming agents in the market. From the above cases, we prove the strength of our Nanhui defoamer. We have a group of excellent defoaming engineers, and an independent laboratory that facilitates defoaming experiments with foams that are difficult for customers to solve. If you want to know more about defoamer products, you can call our hotline: +86 13428601010.
This article is from the manufacturer of Nanhui defoamer (http://www.nhdefoamer.com/), please indicate the source if you need to reprint.
