Wollastonite: Reinforcement, low thermal expansion

Wollastonite is a natural occurring calcium silicate that is formed at about 450°C. The structure of the wollastonite particles depends not only on natural conditions but also to a large extent on the preparation techniques employed. Using specific processing technologies HPF wollastonite powders with particle structures from nearly block-like with a low aspect ratio (LAR) to exceptional acicular structures with a high aspect ratio (HAR) can be produced.

TREMIN 939-products: acicular particles (aspect ratio 8:1) HAR
TREMIN 283-products: granular particles (aspect ratio 3:1) LAR



• hardness 4.5 (Mohs)
• density 2.85 g/cm³
• low thermal expansion: 7*10-6/K (at T 20-300°C)
• excellent reinforcing properties


Key applications:

• engineering technical plastics (PA, PA, PU etc.) for the automotive industry
• fluoro elastomer e.g. for oil sealings
• powder coatings
• friction linings
• corrosion protection i.e. EP/PUR aqueous systems)


High Performance Fillers based on wollastonite: