Wollastonite is a naturally produced calcium metasilicate mineral that is widely used in industrial sectors such as ceramics, plastics, rubber, paints and coatings. Among them, wollastonite consumption is growing fastest in the plastics market.
Wollastonite is used as a filler in plastics and rubbers to take advantage of its low viscosity, high dispersion and low hygroscopicity. In particular, wollastonite crystals have a large length-to-diameter ratio, and their needle-like powder can be used as short fiber filler to reinforce various plastic composite materials. In recent years, wollastonite has also been used to manufacture lightweight, compressive, heat-insulating, and insulating building materials, such as heat-resistant cardboard, white cement, special concrete, and acid-resistant glass. Wollastonite has high resistance and low dielectric constant and is a new type of electrical insulation material that can be used as a substitute for asbestos.
Natural wollastonite has the chemical structure of β-type calcium silicate, which is a mixture of needle-shaped, rod-shaped, and granular particles of various shapes. It absorbs less oil and water, has good chemical stability and electrical insulation properties, and is low in cost.
Wollastonite is used as a plastic mineral filler to increase strength, reduce water absorption, improve thermal and dimensional stability, and improve dielectric indicators and electrical insulation.
Natural wollastonite is crushed and classified through a Raymond mill. After refining, it can be used as plastic filling masterbatch. However, if the plastic filler requires higher performance, wollastonite prepared by a synthetic method can be prepared by heating silica and calcium oxide.
Wollastonite is not only used for plastic filling masterbatch because it has a certain reinforcing effect on plastics, but can also be used to reinforce nylon, polypropylene, polyester, polyformaldehyde, polycarbonate, polyphenylene sulfide, ABS, etc.