Alternative insulating asbestos foam

2001/07/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria

• Kimika

Asbestos, structured in fibers, is used to manufacture materials or fabrics that due to their firelessness require this characteristic, such as insulators subjected to high temperatures. However, asbestos has harmful health effects as it causes cancer. Therefore, researchers have insisted on the synthesis of asbestos substitute materials.

On this occasion, researchers from the Technion Technological Institute of Israel have unveiled the aluminium oxide ceramic foam. For the preparation of the foam, first the crystals containing the metal components and other components are heated and a dissolution is formed. Subsequently, this solution produces a reaction and polymer chains are formed. When the chains are quite long, suddenly the solvent is separated from the polymers.

At that time the solvent reaches the boiling point, thousands of small bubbles are formed and the polymer becomes foam. Finally, the obtained foam is heated to high temperature. Ceramic foam contains between 94 and 96% air per unit volume and can withstand temperatures above 1,700 °C.