I. surface active agent foam formation cause

When the surfactant is mixed with water, the hydrophilic end will dissolve in water, and the hydrophobic side will get out of the water and gather around the water.The surfactant on the surface of the water, the hydrophobic base will leave the water and enter the air, the hydrophilic solution in the water and side by side.When the water is stirred, the air will enter the water, and the hydrophobic base will wrap up the air and become a bubble.Generally speaking, anionic and cationic surfactant foam is the highest, and non-ionic surfactant foam is relatively low.

In most processes, the foam brings a negative impact, meaning the low - and bubble-free surfactants we seek.But in some areas, it is the opposite, such as daily chemicals, body wash and cleansing milk.As for the flotation deinking of the paper deinking area, the surface active agent also needs good foaming performance.

2. The low-foaming surfactant with cleaning function

While discussing low foam surface active agent, must use the condition, process, such as surface active agent of foam in addition to related to its structure, and water hardness, temperature, acid and alkaline pH, pressure etc. There are plenty of contact.

1, soap

Soap can be called a low - foam surfactant in the use of hard water.Sometimes you can use soap to test and distinguish between soft water and hard water. Foam is mostly soft water, and less foam is hard water.The main reason is that in hard water, soap will combine calcium and magnesium ions to form a calcium soap or magnesium soap that is insoluble in water, which can easily form a gap on the surface of the foam, causing the bubble to burst.

2. Polyoxyethylene ether of the EO/PO block of fatty alcohol

As we all know, the condensation of fatty alcohol and EO (ethylene oxide), which is the AEO series, introduces the hydrophilic eeo group, which will achieve excellent wetting, emulsification, cleaning and high foam performance.The PO epoxy propane is the hydro-repellent group, and the introduction of epoxy propane can effectively reduce the surface tension of the foam surface, causing the bubble to burst and disappear.However, the introduction of PO inevitably reduces the content of EO, thus reducing the emulsification and dispersion of surfactants.Therefore, for EOPO block polyether, its emulsification, dispersion and other cleaning functions and low bubbles must be contradictory.The lower the bubble, the worse the other performance.

3. Fatty acid methyl ethyl oxide and its derivatives

Stearic acid methyl ester of fatty acid methyl ester, especially 18 carbon, itself is a kind of antifoaming agent, so 18 carbon stearic acid methyl ester as raw materials of surfactant and the corresponding performance with low foam, and the performance of low foam, unlike EOPO block polyether segment at the expense of the loss on its net washing performance, so it is quite a practical application value of low foam cleaner.

4. Low carbon chain fatty alcohol ether and its derivatives

Low carbon chain fatty alcohol has certain function of defoaming, therefore, with a low carbon chain fatty alcohol as raw material of surface active agent, also the corresponding with the characteristics of low foam, the most common for isooctyl alcohol polyoxyethylene ether, isooctyl alcohol phosphate and isooctyl alcohol ether phosphate has features of low foam.However, the fatty alcohol derivative of low carbon chain is usually only permeable, and other performance is poor, thus limiting its application scope.