We have compiled various applications of gas-phase silica, and this article will take a look at the reasons behind the numerous magical abilities that can transform materials into magical gas-phase silica and achieve these magical effects.


There are two main categories of gas-phase silica: untreated and treated, with the former hydrophilic and the latter hydrophobic. The gas-phase silicon dioxide generated by the gas-phase method is directly accumulated, purified, collected, compressed, packaged, and not treated with other chemical reagents. Its surface retains hydroxyl groups, thus possessing hydrophilicity. When gas-phase silica is treated with chemical reagents, the surface hydroxyl groups are replaced by corresponding groups (usually hydrophobic groups), thus possessing hydrophobicity. This type of product is further divided into two subcategories: fully processed and partially processed. Hydrophobic silica cannot be wetted by water and cannot disperse in water. Its density is greater than that of water, but it can float above the water surface.


Regardless of whether it is hydrophilic or hydrophobic, the principle of action of gas-silicon is generally based on the formation of hydrogen bonds between the hydroxyl groups on the surface of gas-silicon, resin, monomers, and gas-silicon, forming a three-dimensional network structure to achieve related functions.

In addition to the hydroxyl groups on the surface of hydrophobic silica, it can also rely on the modified alkyl groups on the surface of silica to form a three-dimensional network structure. Therefore, hydrophilic silicone gas can only be used in systems with lower polarity (hydrogen bonds cannot be formed at high polarity), while hydrophobic silicone gas is mainly used in systems with higher polarity (it can rely on modified alkyl entanglement). In the adhesive and composite industry, product application requirements include particle size selection (generally speaking, the smaller the silica particle size, the better the effect, but the difficulty of dispersion also increases), and surface modification types (such as dimethyldichlorosilane, hexamethyldisilazane, etc.).

In the field of material application, gas silicon is mainly divided into liquid system, drying system, and solid system. The application mechanisms of different systems are slightly different. The following text will respectively understand:

·Liquid system: Gas phase silica has a large number of hydroxyl groups on its surface, which can form hydrogen bonds between aggregates. When it is fully dispersed in the liquid system, a network structure of silica is formed, which can increase the viscosity of the liquid and produce thixotropy. The main functions of this network are thickening, thixotropy, anti settling, and anti sagging. This characteristic can be widely applied to mechanical spraying of liquid phase materials, resulting in better and thicker spraying effects.

In order to achieve good rheological properties in the system, the moderate dispersion of silica particles in the liquid phase system is a decisive factor. Excessive dispersion can cause complete destruction of the network structure between silica particles, and even if shear force is stopped for a long time, its network structure is difficult to recover.
Drying system: This type of system refers to substances such as powders and particles. Adding a small amount of gas-phase silica to these material systems can promote free flow, prevent agglomeration, and prevent blockage. The microstructure of silicon dioxide aggregates makes it easy to move between large particles in the drying system, and in most cases, it can form a film on the surface of powder like particles, making the particles like sliding ball bearings, making it easy for large particles to slide. This characteristic helps the material pass through equipment with small holes such as valves and nozzles; At the same time, the application of silica can fundamentally solve the problem of rapid formation of products due to moisture absorption and pressure, and has strong adsorption effect, making it an excellent flow promoter.


Solid state system: Gas phase silica is an effective reinforcing agent for cross-linked polymer systems. This is because gas-phase silica can enhance the cohesion of solid systems, as well as the small particle size and open branching properties of aggregates, which enable polymers (additives) to have a larger contact area. The gas-phase method of silica particles relies on the hydrogen bonding formed by the silanol groups on their surface to promote cross-linking between silica particles or between silica particles and methylpolysiloxane, thereby greatly improving the mechanical strength of silicone rubber and other materials.