Wollastonite: Reinforcement, low thermal expansion



Wollastonite a natural calcium silicate that is formed when silicon dioxide and calcium carbonate are fused at a temperature of approx. 450°C. The structure of the individual wollastonite particles depends on their geological origin on the one hand, and on the other it is determined largely by the processing technologies used to refine it. Using specific processing technologies wollastonite powders with particle structures from nearly block-like with a low aspect ratio (LAR) about 3:1 (TREMIN 283®-product series) to exceptional acicular with a high aspect ratio (HAR) about 8:1 (TREMIN 939®-product series) are achieved.

• TREMIN® 939-products: acicular particles (aspect ratio 8:1) HAR
• TREMIN® 283-products: granular particles (aspect ratio 3:1) LAR
• hardness of 4.5 (Mohs)
• density of 2.85 g/cm3
• low thermal expansion: 7*10-6 K-1 (at T 20-300°C)
• excellent reinforcing properties

Key applications
• engineering technical plastics (i.e. polypropylene, polyamide, polyurethane) for the automotive industry
• Fluoro silicone rubber e.g. for oil seal
• friction linings
• powder coatings
• corrosion protection (i.e.epoxy- or polyurethane-based aqueous systems)


  • Vertrieb / Sales - HPF The Mineral Engineers
  • fon +49 (0) 2234 101-415