A Brief Background Introduction to Defoamers

Apr 14, 2021

The role of active ingredients: foam breaking, defoaming, reducing surface tension: Representatives: silicone oil, polyethers, higher alcohols, mineral oils, vegetable oils, etc. [1] (2) Emulsifier function: Disperse the active ingredients into small particles, which are easy to disperse in water, and have better defoaming and anti-foaming effects. Representative: non(octyl)phenol polyoxyethylene ether, soap salt, op series, Tween series, Span series, etc. (3) Carrier function: Conducive to the combination of the carrier and the foaming system, easy to disperse into the foaming system, and combining the two, its own surface tension is low, it is helpful for foam suppression, and can reduce costs. Representative: solvents other than water, such as aliphatic hydrocarbons, aromatic hydrocarbons, oxygenated solvents, etc. (4) Emulsification aids: make the emulsification effect better. Representative: * Dispersant: hydrophobic silica, etc.; * Tackifier: CMC, polyvinyl ether, etc.
Defoaming agent (English name Defoamers, Defoaming Agent) is an auxiliary agent whose function is to eliminate the foam formed by materials in the production process. There are many types of defoamers and their ingredients are quite different. There are many types of Jingqi defoamers, such as shear resistant defoamers, high temperature resistant defoamers, acid and alkali resistant defoamers, solid defoamers, silicon-free defoamers, silicone defoamers, mineral oil defoamers Agent, silicone polyether defoamer, polyether defoamer and so on.

Defoamer definition
A brief background introduction to the defoamer
Antifoaming agent, also known as defoaming agent, is an additive used in food and other processing industries to reduce surface tension, inhibit the generation of foam or eliminate foam. The defoamers that are permitted to be used in my country are emulsified silicone oil, higher alcohol fatty acid ester compound, polyoxyethylene polyoxypropylene quaternary pentatetraol ether, polyoxyethylene polyoxypropanol amine ether, polyoxypropylene glycerol ether and polyoxyethylene 7 kinds of propylene polyoxyethylene glycerol ether, polydimethylsiloxane, etc.

Generally speaking, foam is a coarse dispersion of gas in liquid and belongs to a gas-liquid heterogeneous system. Foam is a thermodynamically unstable system and cannot be stable. The thermodynamic instability of foam is due to the large decrease in the total liquid surface area of ​​the system after the bubble breaks, and the energy (free energy) of the system decreases greatly. Long-term defoaming is also called foam suppression. The length of foam suppression time is the most important indicator of the quality of defoamers. In most cases, we use defoamer to take advantage of its anti-foaming properties, not the initial defoaming properties. Defoaming and foam suppression are relative, and the relative foam suppression performance of products with good defoaming performance will be poor. Defoamers, foam inhibitors and defoamers are collectively referred to as defoamers. Foam breaking: In contrast to foam (foam polymer), it penetrates into the foam from the air side and breaks the foam together. Anti-foaming: Invade the bubbles from the liquid side to combine and destroy the bubbles, making it difficult to produce bubbles. Defoaming: Invade the bubble from the interface of the bubble, and make the bubble close--to float out of the liquid surface.

Silicone defoamers have a wide range of uses and applications. They are used in erythromycin, lincomycin, abamectin, gentamicin, penicillin, oxytetracycline, tetracycline, tylosin, glutamic acid, lysine Acid, citric acid, xanthan gum and other fermentation industries are used as defoamers. It is also used in textiles, printing and dyeing, coatings, dyes, papermaking, printing inks, oil fields, sewage treatment and other fields. When used in printing and dyeing, it has good compatibility with the additives in the dye bath, and does not affect the shade and color fastness.