Application of Hexamethyldisilazane
Hexamethyldisilazane (HMDS) is a colorless, non-toxic, transparent liquid with a slight amine smell, which is widely used in many fields.
Industrial Applications
Semiconductor Field: In semiconductor manufacturing, HMDS is often used as a bonding aid for photoresists, used for silicon wafer surface modification, enhancing the adhesion between photoresists and silicon wafers, inhibiting the invasion of etching solutions, and improving corrosion resistance. Pharmaceutical Industry: HMDS is an important raw material for the synthesis of pharmaceutical intermediates and can be used to synthesize a variety of drugs, such as amikacin, cytokine, azithromycin, penicillin, cephalosporin, fluorouracil, etc. In addition, it is also involved in the synthesis of some antibiotics, hepatitis, tumors, AIDS, cardiovascular and cerebrovascular diseases and other therapeutic drugs. Organic Synthesis Field: In organosilazane chemistry, HMDS can exchange chlorine with chlorosilane monomers to obtain polysilazane, which is more advantageous than the direct ammonia method in synthesis. It can also be used as a group protecting agent and activating agent for the preparation of organosilicon compounds.
Surface treatment of materials: HMDS can be used for the surface treatment of diatomaceous earth, white carbon black, titanium and other powders, and improves the performance and application effect of the materials through the condensation of silicon nitrogen bonds and silicon hydroxyl groups.
Rubber production: As an auxiliary agent for the production of rubber, HMDS can improve the performance of new organosilicon materials such as silicone rubber, silicone oil, silicone resin, such as anti-aging, tear resistance, high and low temperature resistance, corrosion resistance, thermal insulation, hydrophobicity, etc., thereby improving the quality and service life of rubber products.
Other applications: HMDS is also used to reduce the tailing agent adsorbed on the surface of gas chromatography carriers; in electron microscopes, it is used as a desiccant for critical point drying during sample preparation; in pyrolysis-gas chromatography-mass spectrometry analysis, adding it to the analyte can improve the detection sensitivity of the compound.
Chemical properties HMDS is easily hydrolyzed, releasing ammonia (NH3) to generate hexamethyldisiloxane. In the presence of a catalyst, it reacts with alcohol or phenol to generate trimethylalkoxysilane or trimethylaryloxysilane. It reacts with anhydrous hydrogen chloride to release ammonia or ammonium chloride (NH4Cl) to generate trimethylchlorosilane. It can be prepared by reacting trimethylchlorosilane with ammonia (NH3).