Differences in the Use of Silicon and Silica
The Use of Silicon
Silicon exists in nature as a large amount of silicate and quartz minerals. If carbon is the main element that makes up the biological world, then silicon is the main element that makes up the mineral world on Earth. The abundance of silicon in the crust is 27.7%, ranking second among all elements. The most abundant element in the crust is the combination of oxygen and silicon to form silica SiO2, which accounts for 87% of the total mass of the crust. The soil, stones, and sand under our feet, as well as the bricks, tiles, cement, glass, and ceramics we use, are all compounds of silicon that we often encounter in our daily lives. Silicon is a ubiquitous element found all over the world. Due to its easy binding with oxygen, there is no free state of silicon in nature. We introduce the properties, uses, and preparation methods of silicon. Below, we will introduce the properties, uses, and preparation methods of silicon.
The use of silica
Silicon dioxide has a wide range of uses. Rare crystals in nature can be used to manufacture important parts of electronic industry, Optical instrument and handicrafts. Silica is an important raw material for manufacturing Optical fiber. Generally pure quartz can be used to make quartz glass. Quartz glass has a small expansion coefficient, equivalent to 1/18 of ordinary glass, and can withstand temperature fluctuations. It has good acid resistance (except for HF), so quartz glass is often used to manufacture high-temperature resistant chemical instruments. Quartz sand is commonly used as a raw material for glass and building materials.
There are many methods for obtaining matting agents from silica, and they can be mainly divided into two categories based on their manufacturing process. One type is produced by hydrothermal method, and the form of silicon dioxide produced is relatively soft. Products made of silicone have a harder texture. After treatment, both types of products can be made into standard silica matting agents. The treatment process refers to the use of organic (paraffin) or inorganic materials to modify the surface of silica to a certain extent. Compared with silicone matting agents, treated silica has different particle sizes, particle size distributions, and pore volumes. The thermal extinction agents also differ in particle size and distribution. There are also differences between untreated and processed products. At present, there is only one extinction agent suitable for special occasions, which is manufactured by pyrolysis method and has strong extinction efficiency, and is particularly suitable for water-based coating systems. The extinction effect of silica is relatively strong, and higher concentrations may lead to an increase in viscosity. There is a tendency to precipitate during storage, especially untreated silica. To avoid accumulation, we can use paraffin or pyrolysis method of silica. This extinction agent can adjust the extinction at 45 °, 60 °, and 85 ° directions. Coatings with the addition of silica matting agent can be covered. All of these are 'still in' products. The synthesized Aluminium silicate can partly replace titanium dioxide as a high-quality additive, and can be used in lotion primer. The product can show a balanced matting effect in the dry lotion paint film. It can be used as a matting agent in a long oil alkyd resin system, but must be dispersed together with pigments and fillers. Except in powder coating systems, silica matting agents can be applied to all coatings.