ALUMINUM BORATE

The melting method mixes alumina and boric acid or boron oxide, melts at 2100°C, and then cools to grow into whiskers. This method can only grow into whiskers over tens of microns. In the gas phase method, water vapor is passed into the gaseous aluminum fluoride and boron oxide at 1000-1400°C to obtain aluminum borate whiskers. This method is not easy to operate. The internal melting method reacts aluminum oxide or a compound that generates aluminum oxide at high temperatures with boron oxide at 1200 to 1400°C, and the boron oxide also acts as a flux to finally obtain aluminum borate whiskers. This method can only obtain large-sized whiskers. At the same time, because boron oxide acts as a flux, the generated whiskers are dissolved and the yield is reduced. The external melting method is above 1000°C, adding fluxes that are not related to the reaction (such as alkali metal chloride, sulfate or carbonate) into the alumina and the raw materials that produce boron oxide, and grow into whiskers at 1000-1200°C. After the reaction, treat with water to remove the flux and separate the whiskers. When the reaction temperature is 800～1000℃, 2A12O3?B2O3 whiskers are obtained. Compared with the melting method and the gas phase method, this method has lower reaction temperature, lower energy consumption and higher yield. This method is generally used in industry. Using tri-alkali aluminum sulfate [M3 AI(S04)3] (M is alkali metal) and boron oxide, oxyacid, or alkali metal borate as raw materials, the molar ratio of aluminum to boron is 6:4～ 9:2 is mixed, and the mixture is reacted at 700-1200°C to obtain aluminum borate whiskers.

Can be used as a reinforcement material for plastics, metals, ceramics, etc. When used as a plastic reinforcing agent, compared with glass fiber, it can play a role in reinforcing plastic moldings with small and complex shapes. Give products such as directionality. It can also be used as a reinforcing material for polycarbonate resin.