In the fiber optic cable manufacturing process, there are usually three ways to prevent water and moisture, that is, inflation, filling with ointment (fiber paste and cable paste) or using dry super absorbent materials. Among them, filling ointment in optical fiber and cable is the most common practice in the production of optical fiber and cable at home and abroad.
The traditional hot filling process adopts hot-melting filling petroleum ointment mixture. This ointment and its filling process have disadvantages such as complicated filling equipment, difficult process stability, high energy consumption and environmental pollution. In order to improve the filling process and overcome the hot-melt oil Due to the shortcomings of the paste, people have developed a thixotropic filling paste that can be filled at room temperature, that is, a cold filling paste.
Cold filling paste is generally composed of base oil, thickening thixotropic agent, delamination inhibitor, antioxidant and other additives. In practice, it has been found that fumed silica is an ideal thickening thixotropic material for optical fiber cable cold filling paste agent.
Fumed silica is an amorphous silica product obtained by high-temperature hydrolysis of halosilanes in a hydrogen-oxygen flame. It has the characteristics of small particle size, large specific surface area, high surface activity and high purity. Its thickening and thixotropic properties The mechanism is mainly realized through the interaction of the hydrogen bonds of the surface silanols.
Fumed silica is used as a thickener and thixotropic agent in fiber optic cable filling materials, and plays an important role in improving the quality of filling paste.