Silicon dioxide(CAS#14808-60-7)
| Risk Codes | R37 – Irritating to the respiratory system |
| Safety Description | S24/25 – Avoid contact with skin and eyes. |
Silicon dioxide(CAS#14808-60-7)
quality
Physical properties of silica: colorless transparent crystals or amorphous powder, odorless. The melting point is 1710°C (square quartz), 1670°C (scale quartz); The boiling point is 2230°C. Aorphous powder can act with alkali, has stable physical and chemical properties, is easy to form, is inert, the melt is layered, and the expansion coefficient is small when heated.
Chemical properties of silica: almost insoluble in hydrofluoric acid, soluble in hydrofluoric acid to form silicon fluoride gas, and slowly react with hot concentrated phosphoric acid.
Preparation method
Using ethyl orthosilicate as raw material, it is first distilled efficiently to collect fractions at 160~168°C. Then, ethyl orthosilicate is mixed with ammonia and heated, and the reactants change from cloudy to viscous until the solution boils. Stop stirring, let the solution settle, and after centrifugation, dry it at low temperature for a certain period of time. Finally, the product is obtained by scorching at 900°C and cooling naturally.
use
Masking film and protective layer: impurity diffusion in transistors and integrated circuits; As a filler, it is used in epoxy casting, optical fiber, coating and other fields; It is used in the manufacture of glass, emission spectroscopy analysis reagents, and control of antimony concentration during antimony expansion in solid circuit production.
