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Wollastonite is a naturally occurring mineral with many unique characteristics. Through advanced processing, it has become one of the most versatile functional fillers in the marketplace. Wollastonite increases the performance of many products including plastics, paints and coatings, construction materials, friction, ceramic and metallurgical applications to name a few.

Wollastonite is an industrial mineral comprised chemically of calcium, silicon and oxygen. Its molecular formula is CaSiO3 and its theoretical composition consists of 48.28% CaO and 51.72% SiO2. Natural wollastonite may contain trace or minor amounts of various metal ions such as aluminum, iron, magnesium, potassium and sodium. Wollastonite is rarely found by itself and generally contains other minerals like calcite, garnet and diopside that are removed during processing.

Optimum performance is created by properly matching the correct coupling agent at the right concentration level to the polymer system. Overall, the benefits of a surface modified wollastonite are improved physical properties, improved processing along with improved dispersion of the resin.

Plastics: In plastics, wollastonite improves the durability of the composite due to its acicular or needle-like structure. It also enhances electrical insulating properties, adds fire resistance, and improves dimensional stability. Finer particle size grades provide improved scratch and impact resistance compared to other materials. The application of surface treatments like silanes on the wollastonite substrate changes the mineral from a utilitarian filler to a functional component of a polymer composite. This in turn adds performance values which the base resin alone does not possess. Optimum performance is created by properly matching the correct coupling agent at the right concentration level to the polymer system. Overall, the benefits of a surface modified wollastonite are improved physical properties, improved processing along with improved dispersion of the resin.

Construction: Wollastonite has found application as a substitute for asbestos in fire-resistant building products used in the construction industry. As a functional additive, wollastonite improves flexural and impact strengths. Its low thermal conductivity and high aspect ratio structure also makes wollastonite an attractive addition for applications requiring fire resistance. Wollastonite finds application in interior and exterior construction boards, roof tiles, shaped insulation products, sheets, panels and sidings.

Kaolin, or China clay, is nearly white in color. It is distinguished from other industrial clays based on its fine particle size and pure coloring. Its ability to disperse in water make it an ideal pigment.

The primary constituent in kaolin is the mineral kaolinite, a hydrous aluminum silicate formed by the decomposition of minerals such as feldspar.

The name kaolin derives from the Chinese and means high ridge. High ridge is a reference to the hill in south-eastern China where the clay was originally discovered and used. In the 7th and 8th centuries, the Chinese were the first to use kaolin to make porcelain. It was not until centuries later that other areas of the world could duplicate the process.

The white color of the mineral can either be naturally occurring, or can result after processing which removes minerals and other color-bearing compounds. The small particle size of the mineral contributes to its white color by scattering light.

Calcium carbonate, or CaCO3, comprises more than 4% of the earth’s crust and is found throughout the world. Its most common natural forms are chalk, limestone, and marble, produced by the sedimentation of the shells of small fossilized snails, shellfish, and coral over millions of years. Although all three forms are identical in chemical terms, they differ in many other respects, including purity, whiteness, thickness and homogeneity. Calcium carbonate is one of the most useful and versatile materials known to man.

Many of us encounter calcium carbonate for the first time in the school classroom, where we use blackboard chalk. Chalk has been used as a writing tool for over 10,000 years and is a fine, microcrystalline material. As limestone, calcium carbonate is a biogenic rock, and is more compacted than chalk. As marble, calcium carbonate is a coarse-crystalline, metamorphic rock, which is formed when chalk or limestone is recrystallised under conditions of high temperature and pressure. Large deposits of marble are found in North America and in Europe; e.g., in Carrara, Italy, the home of the pure white “statuario” from which Michelangelo created his sculptures.