There are two kinds of silica gel: one is precipitation silica gel; One is the gas phase silica gel.
The tear strength and elongation of silica reinforced by gas phase method are better than that of silica reinforced by precipitation method. Transparency in the gas phase. The opacity or translucency of a precipitation process.
The difference lies in the white carbon black added:
Vapor phase silicone rubber is used in the gas phase method of white carbon black, the white carbon black using chemical vapor deposition (CAV) method, also known as pyrolysis, dry or combustion method.
Precipitation silicone rubber is the production method of precipitated silica and precipitated silica (silica), and its process route is in general: First, using fuel or gas at high temperature will be quartz sand and soda soda reaction to produce industrial sodium silicate, industrial sodium silicate water prepared into a certain concentration of dilute solution, and then under certain conditions to add some acid, so that silica precipitation, and then after cleaning, filtration, drying, crushing, the product white carbon black. Precipitation method is divided into acid method, sol method, carbonization method and many different specific methods, our country mainly uses acid method. The acid method is to react the soluble silicate with sulfuric acid (or other acids). When the reaction liquid reaches a certain pH value, the acid reaction is stopped, and the aging is carried out. Then the product is filtered and cleaned repeatedly with water, after removing Na2SO4, the product is sent to dry and crushed.
 
Gas phase silica gel tear resistance is better, suitable for:, pressure cooker ring, silica gel line and so on;
Precipitation method silica gel strike life is better, suitable for: remote control keys, mobile phone keys, pads, etc.