A new generation of defoamers and their characteristics

The above-mentioned defoamers are all traditional defoamers, and their defoaming substances are all water-insoluble substances, and proper amount of emulsifiers, extenders, etc. need to be added to make them quickly and uniformly dispersed in the water-based paint to exert their defoaming effect. If for some reasons, such as the common construction method of adding water to dilute before painting, the emulsifier will be separated from the surface of the defoaming material, so that the water-insoluble defoaming material will easily cause shrinkage on the surface of the coating film. , This is a common disadvantage of traditional defoamers. In addition, it is very difficult for a high-viscosity coating system to achieve an ideal defoaming effect. This is because the high-viscosity system makes it difficult for the liquid to flow between bubbles, and the film wall of the bubbles has a certain thickness, which makes it difficult to make it Rupture, which will cause a lot of pinholes in the paint film. Therefore, it is necessary to develop new defoamers to solve the problems that traditional defoamers cannot solve.

People get inspiration from the structure of a new type of Gemini surfactant, which is a substance formed by linking two or more monomer surfactants together through a chemical bond. For example, two common surfactants with single-chain single-chain single-head groups are connected together by chemical bonds at the ionic head groups, so that the resulting special structure has certain special properties, especially higher surface activity. And other physical and chemical properties.

The characteristics of this structure are:

• At least 2 hydrophobic chains and 2 hydrophilic groups;
• Hydrophobic chains can be hydrocarbon chains of different chain lengths;
• The hydrophilic group can be anionic, cationic or non-ionic, and the two hydrophilic groups in the same molecule can be different;
• According to the difference of the spacer chain, it can be divided into rigid and flexible structures, and because of the heteroatoms, its hydrophobic and hydrophilic abilities are also different, which can be divided into hydrophobic and hydrophilic;
• Most Gemini surfactants have two identical hydrophobic chains and hydrophilic groups.

In view of Gemini surfactant technology, the defoamer is designed into a network-like supramolecular structure, so that it has many anchor points, and also has a certain self-emulsification effect, so there is no need to use emulsifiers. The problem of shrinkage caused by such a structure can make it have a certain wetting effect on the substrate, so the amount of wetting agent can be appropriately reduced. This is a major change in water-based defoamers, which are called molecular defoamers. For example, INVELY’s 8200 defoamer is an enhanced mineral oil-based defoamer, suitable for all kinds of high-gloss pure acrylic, styrene acrylic and vinegar paint, its performance is equivalent to foamaster-st 10.

The advantages are:

• The addition amount is 1/3 or even 1/2 lower than traditional defoamers, and the cost can be reduced by at least 20%;
• During storage, there will be no delamination of ordinary mineral oil defoamers;
• Especially effective when used in vinegar-acrylic and pure acrylic paint;
• The foam breaking speed is faster than ordinary defoamers, especially the effect of breaking fine foam.

Amber Zhang Ms.

Foreign trade 

Zhejiang Ruico Advanced Materials Co., Ltd. (Stock No.873233)

Add: No.188, Liangshan Road, Linghu Town, Nanxun District, Huzhou City, Zhejiang Province, China 313018

Phone: +86 (572) 2903236

Fax: +86 (572) 2905222

Wechat: 15534631339

Website: www.ruicoglobal.com 

Email: [email protected]