1、Hydrophilic fumed silica   
Hydrophilic fumed silica is produced by hydrolyzing volatile chlorosilanes in a hydroxide flame. Chemically, these loose white powders consist of high purity amorphous silica. Hydrophilic silica can be wetted with water and can be dispersed in water. In addition to applications in traditional industries such as polyester, silicones, paints and coatings, hydrophilic fumed silica products are increasingly being used successfully in high-tech applications. The nanoparticle properties and high purity of fumed silica have led to its use in the electronics and fiber optic industries. Hydrophilic fumed silica products have an amorphous structure as analyzed by x-ray. Depending on the market and the application area, we can offer primary particles with different particle sizes and different specific surface areas. Some fumed silica products can be supplied compressed and some are pharmaceutical grade.
2、Functions of hydrophilic fumed silica
Suitable for processing and adjustment to optimum rheology; reinforcement of silicone elastomers; thickening of non-polar liquids; flow aid for food and industrial powders; high chemical purity; excellent insulating properties even at high temperatures; conversion of liquids into powders, e.g. pharmaceuticals, cosmetics.
3、Hydrophobic fumed silica
Hydrophobic fumed silica is produced by the chemical reaction of hydrophilic fumed silica with reactive silanes (e.g. chlorosilanes or hexamethyldisilazanes). It is hydrophobic (hydrophobic) and cannot be dispersed in water. Various types of hydrophobic fumed silica have been developed to solve specific technical problems in industry. For example, hydrophobic fumed silica is produced by modifying hydrophilic grades of fumed silica with silane or siloxane treatments, where the chemical treatment agent is chemically bonded to the original hydrophilic oxide in the final product.
In addition to the above advantages of hydrophilic products, hydrophobic fumed silica products are characterized by low hygroscopicity, very good dispersibility, and rheology modification even for polar systems. Some products, which are structurally modified on the basis of hydrophobic treatment, can provide further assistance to customers in developing new products and improving product performance. For example, in liquid systems, hydrophobic fumed silica can be added at high levels with little effect on the viscosity of the system.
4、Functions of hydrophobic fumed silica
Optimum rheology for process use; thickening of polar liquids, e.g. epoxy resins; reinforcing of silicone elastomers; high additives, e.g. in molded products; good hydrophobicity to improve corrosion resistance; improved dielectric properties, e.g. in cable compounds; powder flow aids, e.g. in powder coatings and extinguishing agents, etc.; improved scratch resistance in coatings and plastics.

Room termperature curing polysilazane, pls check IOTA 9150, IOTA 9150A. 
High termperature curing polysilazane, pls check IOTA 9108, IOTA 9118.