The difference between hydrophilicity and hydrophobicity of fumed silica

Hydrophilic fumed silica is obtained by hydrolysis of volatile chlorosilane in a hydrogen oxygen flame. From a chemical perspective, these loose white powders are composed of high-purity amorphous white carbon black. Hydrophilic silica can be wetted with water and can disperse in water. In addition to its application in traditional industrial fields such as polyester, organosilicon, paint, and coatings, hydrophilic gas-phase silica products are increasingly being successfully applied in high-tech fields. The nanoparticle characteristics and high purity of gas-phase white carbon black play a dominant role in its application in the electronics and fiber optic industry. The hydrophilic gas-phase white carbon black product has an amorphous structure after X-ray analysis. According to different markets and application fields, we can provide products with native particles of different sizes and specific surface areas. Some gas-phase white carbon black products can be supplied after compression, and some products are pharmaceutical grade.
The function of hydrophilic gas-phase silica: suitable for processing and adjusting to the optimal rheological properties; Reinforcement of silicone elastomers; Thickening of non-polar liquids; Flow aids for food and industrial powders; High chemical purity; Excellent insulation performance even at high temperatures; Liquid transforms into powder, such as in medicine and cosmetics.
Hydrophobic gas-phase silica is produced by a chemical reaction between hydrophilic gas-phase silica and active silane (such as chlorosilane or hexamethyldisilane). It has hydrophobicity and cannot disperse in water. In order to solve some special technical problems in industry, various types of hydrophobic gas-phase white carbon black have been developed. If hydrophobic gas-phase silica is produced by treating modified hydrophilic silica with silane or siloxane, the chemical treatment agent is bonded to the original hydrophilic oxide in the final product. In addition to the above advantages of hydrophilic products, the characteristics of hydrophobic gas-phase white carbon black products are: low moisture absorption, good dispersibility, and rheological adjustment ability even for polar systems. Some products, after hydrophobic treatment and structural modification, can provide further assistance for customers to develop new products and improve product performance. For example, in liquid systems, hydrophobic gas-phase silica can achieve high addition levels, while having little effect on the viscosity of the system.