In the fields of materials science and chemical engineering, the significance of hexamethyldisilazane is becoming increasingly prominent, and its preparation processes have also become a focal point of industry attention. Currently, two commonly used preparation processes are mainly adopted in the industry, laying the foundation for the large-scale production and application of this compound.

The first commonly used process utilizes hexamethyldisilazane as the raw material. Initially, hexamethyldisilazane is dissolved in an organic solvent such as toluene. Hydrogen chloride gas is then introduced, and a reaction occurs at low temperatures to generate a chlorosilane intermediate and release ammonia gas. Subsequently, liquid ammonia or an amine compound is added, and through ammonolysis or aminolysis reactions, hexamethyldisilazane is obtained. This method features readily available raw materials and mild reaction conditions, making it suitable for industrial-scale production. However, it generates ammonium chloride as a by-product, which imposes certain requirements on the corrosion resistance of the equipment.

The other process starts with silicon powder. First, the silicon powder undergoes activation treatments such as acid washing and drying. Then, it reacts with methylchlorosilanes in the presence of catalysts like copper-zinc under high-temperature and high-pressure conditions to produce a mixture containing the target product. Finally, the product is separated and purified through减压蒸馏 (reduced pressure distillation) or 精馏 (rectification). This process boasts low raw material costs and is suitable for continuous production. Nevertheless, it involves harsh reaction conditions, numerous side reactions, and complex separation and purification steps.

With technological advancements, researchers are actively exploring more environmentally friendly synthetic routes, such as catalytic cracking methods, aiming to reduce by-products and improve atomic utilization. These commonly used preparation processes, along with innovative explorations, will continue to propel the hexamethyldisilazane industry towards higher efficiency and environmental sustainability.

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