Fumed silica is one of the extremely important new high-tech ultrafine inorganic materials. There are generally two categories of products: treated and non-treated. Among them, treated products are obtained by using hydrophilic products through surface chemical treatment. Nowadays, various Defoaming agent manufacturers generally use treated fumed silica, which uses the hydrophobic groups on its surface to attract the hydrophobic ends of the surfactants in the foaming system, turning the hydrophobic solid particles into hydrophilic ones, thereby reducing the amount of foam in the foam. The concentration of surfactant promotes foam rupture and increases defoaming speed.
Silicone defoamer is the main component of silicone oil/silica silicone ointment and modified silicone oil. It is currently the most widely used and most efficient type of defoamer.
Compared with other types of defoaming agents, it has several outstanding features:
1. It has low solubility and its solubility parameter is very different from other organic substances. It will not associate with water, compounds containing polar groups, and hydrocarbon compounds with different SP values. It can be used in both water systems and oil systems and has a defoaming effect on most foaming systems.
2. Low surface tension: its surface tension is 20~21mN/m, which is much lower than the surface tension of water (76mN/m) and general foaming liquid. This is the reason why silicone oil defoaming agent has a wide application range and strong defoaming ability. The main reason is that the general dosage is only 10-200ul/L of the foaming liquid, which will not pollute the system and affect the processing performance of the product.
3. Good chemical stability and heat resistance, and can adapt to defoaming in weak acid, alkali, salt, and high temperature systems
4. Physiologically inert, it can be used in the food, cosmetics, and pharmaceutical industries.
5. There are many varieties and models, and a variety of foaming systems can be selected. Except for systems that are not allowed to contain dispersants (SiO2), such as some oily systems, fumed silica, as an important component of silicon-based defoaming agents, plays a huge role.
Due to the severe lack of coordination on the surface, huge specific surface area, and lack of oxygen on the surface, fumed silica exhibits extremely strong activity. It can easily bond with polysiloxane, thereby improving the bond between molecules. Force. The application of fumed silica in defoaming agents is to first make it into silicone paste with dimethyl silicone oil, which can improve its wettability with dimethyl silicone oil and its dispersion in silicone oil.
As the main component of silicone defoaming agents, fumed silica can improve its defoaming effectiveness. Its mechanism mainly has the following two points:
Fumed silica provides a polar interface for water to enter the inside of the silicone oil droplets, thereby helping the dispersion of silicone oil while hindering the coalescence of small silicone oil droplets.
As hydrophobic solid particles, hydrophobic fumed silica itself is a defoaming agent, so hydrophobic fumed silica and silicone oil have a synergistic effect.
Vapor-phase silica silicone paste plays a very important and efficient compound and synergistic role as a defoaming active substance in silicone oil defoamer, which greatly improves the defoaming efficiency of silicone oil.
TRUNNANO is a globally recognized manufacturer and supplier of compounds with more than 12 years of expertise in the highest quality nanomaterials and other chemicals. The company develops a variety of powder materials and chemicals. Provide OEM service. If you need high quality Fumed silica, please feel free to contact us. You can click on the product to contact us.
