Foamed silicate structures

摘要

Moulded shapes having excellent thermal, mechanical and accoustical properties are prepared by (1) forming a mixture containing in parts by weight about one part alkali metal silicate, 0,02-0,7 parts of inorganic fibrous silicate and 2-10 parts of water (2) heating the mixture to 140-360 DEG C. (3) crushing the heated mixture to a particle size 0,1-10mm (4) heating the particles in a mould at 700-900 DEG C. to obtain a foamed structure and (5) cooling the foamed structure to below the softening temperature to obtain a rigid structure. Exemplified inorganic fibrous silicates include glass wool, basalt wool, rock wool, asbestos wool and mixtures thereof. Additionally alkaline earth carbonates, e.g. calcium carbonate; pulverised stone-like water-insoluable silicates, e.g. pumice stone; and colouring salts, e.g. cobalt sulphate, potassium chromate, cadmium sulphide and copper and iron salts (iron chloride in Example 4) may be added to the initial silicate mixture. Reinforcing rod members may be included in the structures or the foam structures may be used to make laminates with other material such as glass, metal concrete and plastics; it is also possible to coat the foamed structure with films of either plastic or inorganic material.