What are the properties of defoamers? What can be used?
Release time :
2014-07-24
Use of defoamer There are many kinds of defoamers, such as organosiloxane, polyether, silicon and ether graft, amine, imine and amide, which have the characteristics of faster defoaming speed, longer foam inhibition time, wider range of applicable media, and even harsh media environment such as high temperature, strong acid and strong base. It is widely used to remove harmful foam produced in latex, textile sizing, food fermentation, biomedicine, coating, petrochemical, paper making, industrial cleaning and other industries.
Bubbles and foams often accompany people’s life and production. Sometimes it is necessary to use them, such as flotation, fire fighting, dust removal, washing, foam ceramics and plastics manufacturing, etc; Sometimes it needs to be eliminated, such as fermentation, coating, paper making, printing and dyeing, elimination of internal organ gas, boiler water, wastewater treatment and prism (or glass) manufacturing. The so-called “bubble” or “bubble” refers to the existence of insoluble gases in liquids or solids, or in independent bubbles wrapped in their films. Many bubbles gather together and are separated from each other by a thin film, which is called foam. Bubble is a dispersion system with gas/liquid, gas/solid and gas/liquid/solid interfaces. The latter is commonly used in mineral processing and oilfield systems. Generally speaking, pure water and pure surfactant do not bubble, because their surface and interior are average, it is difficult to form elastic films, even if they are formed, they will disappear instantly. However, there is a surfactant in the solution. After the bubble is formed, due to the intermolecular force, the hydrophilic and hydrophobic groups in its molecules are adsorbed by the bubble wall, forming a regular arrangement. The hydrophilic group faces the water phase, and the hydrophobic group faces the bubble, thus forming an elastic film on the bubble interface, which is not chaotic and is not easy to break under normal conditions. The stability of foam is related to surface viscosity and elasticity, electric repulsion, movement of surface film, temperature, evaporation and other factors. Furthermore, bubbles are inversely related to the surface tension of the liquid. The smaller the tension, the easier the bubbles will be. In life and production, sometimes bubbles rise, which brings people a lot of inconvenience, so it is necessary to defoaming. All factors that can destroy the stability of foam can be used for defoaming. Defoaming includes two factors: “foam suppression” and “foam breaking”. Foam suppression is to suppress the generation of foam in the liquid, while foam breaking refers to the destruction of formed bubbles. Relatively speaking, suppressing the generation of foam is more meaningful and more lasting than destroying the generation of foam. The silicone defoamer has this function. It can reduce the surface tension of water, solution, suspension, etc., prevent the formation of foam, or reduce the original foam, usually with a selective effect. General physical defoaming method is difficult to instantly defoaming, while chemical and interface defoaming are very fast, convenient and efficient.
In a word, defoamers refer to agents with chemical and interfacial chemical defoaming effects. As defoamer, it has low carbon alcohol, mineral oil, organic polar compound and silicone resin. Its forms include oil type, solution type, emulsion type and foam type. As defoamer, it has the characteristics of strong defoaming force, stable chemical property, physiological inertia, heat resistance, oxygen resistance, corrosion resistance, gas dissolution, breathability, easy diffusion, easy penetration and seepage, difficult to dissolve in the defoamer system without physical and chemical effects, low consumption of defoamer, high efficiency, etc. Defoamers have a wide variety of uses. The process of “foam inhibition” and “foam breaking” of antifoam agent is: when the system is added with antifoam agent, its molecules are distributed on the liquid surface in disorder, and the elastic film is formed by pressing, which stops the foam production. When a large amount of foam is produced in the system, the antifoam agent is added, and its molecules immediately spread on the foam surface, spreading rapidly, forming a very thin double film layer, which further diffuses, penetrates and infiltrates, and invades in layers, thus replacing the thin wall of the original foam film. Because of its low surface tension, it flows to the liquid with high surface tension that generates foam. In this way, the antifoam molecules with low surface tension continuously diffuse and permeate between the gas-liquid interface, making its membrane wall thinner rapidly. At the same time, the foam is strongly pulled by the nearby film with high surface tension, which leads to the stress imbalance near the foam, leading to its “bubble breaking”. Defoamer molecules that are insoluble in the system re enter the surface of another foam film. If repeated, all foam will be destroyed.
Shanghai Yike Chemical Technology Co., Ltd., a branch invested by YCK Canada in China, is fully responsible for the sales and technical support of YCK chemical additives in China. At present, YCK chemical additives have been widely used in paint, ink, leather and plastic industries. From the very beginning of its establishment, Shanghai Yike Chemical Co., Ltd. has established a perfect after-sales service system, adhering to YCK’s professional spirit of “taking the success of customers as its own responsibility”. In order to provide customers with quick, timely and satisfactory technical support, the company has set up representative offices in Shanghai, Guangzhou and Chengdu respectively, equipped with laboratories and a group of engineers with years of experience as technical service and support centers in various regions. All staff of Shanghai Yike Chemical Technology Co., Ltd. warmly welcome colleagues at home and abroad to join hands to promote the YCK brand and create a brilliant tomorrow.