What are the raw materials of fiberglass?
Fiberglass is an inorganic non-metallic material with excellent performance. Its main components are SiO2, Al2O3, CaO and MgO, accounting for about 90% of the fiberglass components. It is mainly introduced from natural mineral raw materials such as pyrophyllite, kaolin, quartz sand, limestone, dolomite, colemanite and magnesia stone. These mineral raw materials are ground into ore powder according to a certain formula, mixed with chemical raw materials such as boric acid and soda ash, and manufactured through high-temperature melting in a pool kiln and wire drawing.
From the perspective of the cost structure of fiberglass production, mineral raw materials such as pyrophyllite, quartz sand, and limestone account for about 21.7% of the cost, of which pyrophyllite accounts for about one-third, and the sum of quartz sand and limestone also accounts for a certain share.
Pyrophyllite
Pyrophyllite is a layered aluminum silicate clay mineral with a 2:1 crystal structure and a chemical formula of Al2[Si4O10](OH)2. The main purpose of using pyrophyllite in fiberglass is to introduce Al2O3 to replace aluminum powder to reduce costs and improve the mechanical strength of fiberglass. Among them, the Al2O3 mass fraction is preferably 16%-22% of the aluminum pyrophyllite. Too high or too low Al2O3 mass fraction has a great impact on the production process.
Kaolin
Kaolin mainly provides SiO2 and Al2O3 in fiberglass production. Fiberglass companies in Europe and the United States mostly use selected or high-quality kaolin instead of pyrophyllite as fiberglass raw materials. my country's kaolin is mainly divided into: coal-based kaolin and non-coal-based kaolin. Among them, the SiO2 and Al2O3 content in hard kaolin meets the requirements of fiberglass raw materials. Through magnetic separation, flotation and other mineral processing technologies to reduce the content of Fe2O3 and TiO2 in the raw materials, and calcination process to reduce the COD value, hard kaolin can be used as a high-quality fiberglass production raw material with stable quality.
Quartz sand
Quartz sand, also known as silica sand, is mainly composed of silicon dioxide and is an important raw material for nearly 100 industrial products such as glass, electronics and electrical appliances. my country is rich in quartz mineral resources, including natural crystal, quartz sandstone, quartzite, powder quartz, vein quartz, natural quartz sand and granite pegmatite quartz.
Quartz sand is distributed in most provinces and regions, but the quartz resources in my country are scattered and mainly small and medium-sized. The main domestic quartz sand producing areas are: Donghai and Xinyi in Jiangsu, Qichun in Hubei, Fengyang and Bengbu in Anhui, Heyuan in Guangdong, Zhundong in Xinjiang, Yinan in Shandong, Lingshou in Hebei, etc.
Chemical raw materials
The chemical raw materials used in the production of fiberglass are mainly used for the preparation of boric acid, soda ash and other sizing agents. In the production of fiberglass, the sizing agent can effectively bond the fiber monofilaments into raw fibers and avoid the adhesion between the yarns during the unwinding process. At the same time, it protects the yarns from wear and tear during various manufacturing stages of the fiber. According to the different process requirements of the molded products, the sizing agent gives the fiber certain special properties, such as bundling, short cutting, dispersion, etc., which can improve the compatibility and adhesion between the fiber and the resin substrate.
