Cate foams method for improving the cellular structure of rigid low density sili

Abstract

Abstract THE ADDITION OF A FINELY DIVIDED COMPATIBLE POWDER TO A HYDRATED ALKALI SILICATE COMPOSITION PROMOTES THE UNIFORM INITIATION OF BUBBLE FORMATION THROUGHOUT THE MIXTURE. DURING THE FORMING OF THE MIXTURE, THE PARTICLES OF POWDER ACT AS NUCLEATION CENTERS FOR THE GENERATION OF FOAM BUBBLES BY THE WATER OF HYDRATION WHICH CONSTITUTES THE BLOWNING AGENT. THE POWDER MAY BE CHOSEN FROM NONREACTIVE OR ONLY SLIGHLY REACTIVE MATERIALS SUCH AS CARBON BLACK, SILICA, GLASS POWDER, GLASS FIBERS, FERRIC OXIDE (FE2O2) METAL POWDER AND POWDERS OF ORGANIC POLYMERS SUCH AS POLYETHYLENE AND POLYVINYL CHLORIDE. ALKALI METAL SILICATE FOAM AND IN PARTICULAR SODIUM SILLICATE FOAM, MAY BE PRODUCED BY THE KNOWN LIQUID, GEL OR SOLID PROCESSES, INVOLVING THE RAPID INPUT OF HEAT ENERGY, PREFERABLY MICROWAVE ENERGY. THE ADDITION OF FINELY DIVIDED METAL POWDER TO AN ALKALI METAL SILICATE COMPOSITION MAY CONTRIBUTE HEAT ENERGY BY EXOTHERMIC REACTION DURING THE FOAMING OF THE SILICATE BY INPUT OF THERMAL ENERGY AND FURTHER MAY AS RESULT OF FORMATION OF INSOLUBLE PRODUCTS CONTRIBUTE TO THE INSOLUBILIZATION OF THE FOAM ARTICLE PRODUCED THEREBY. IN PARTICUALR THE USE OF SUCH METAL POWDER INCREASE THE EFFICIENCY OF ABSORPTION OF MICROWAVE HEAT ENERGY IN THE FOAMING STEP.

Inventors

• 👤 R Rao

Bibliographic Details