Synthetic microspheres and methods of making same

US7878026B2 · kind B2 · utility

Assignee

• James Hardie Technology Limited · IE

Inventors

• Amlan Datta · Ashland, US
• Hamid Hojaji · Kensington, US
• David L. Melmeth · Fontana, US
• James A. McFarlane · Sydney, AU
• Thinh Pham · Sydney, AU
• Noel E. Thompson · Parramatta, AU
• Huagang Zhang · Yucaipa, US

Key dates

• Filing date: Aug 25, 2003
• Grant date: Feb 1, 2011
• Expiry date: May 19, 2025

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/2996
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A synthetic microsphere having a low alkali metal oxide content and methods of forming the microsphere and its components are provided. The synthetic microsphere is substantially chemically inert and thus a suitable replacement for natural cenospheres, particularly in caustic environments such as cementitious mixtures. The synthetic microsphere can be made from an agglomerate precursor that includes an aluminosilicate material, such as fly ash, a blowing agent such as sugar, carbon black, and silicon carbide, and a binding agent. The synthetic microsphere is produced when the precursor is fired at a pre-determined temperature profile so as to form either solid or hollow synthetic microspheres depending on the processing conditions and/or components used.