Abstract: A low density material and a method for preparing a low-density material and precursor for forming a low-density material are provided. An aqueous mixture of inorganic primary component and a blowing agent is formed, the mixture is dried and optionally ground to form an expandable precursor. Such a precursor is then fired with activation of the blowing agent being controlled such that it is activated within a predetermined optimal temperature range. The firing conditions are also controlled to provide a low density sphere containing a heterogeneous sphere wall structure comprising a combination of amorphous glass and a crystalline phase or gas phase or both.

Abstract: Shaped geopolymeric particles, fibers, and articles incorporating at least one geopolymer are provided; the geopolymeric particles, fibers, and articles having a structure that is solid, foamed, hollow or with one or more voids. Geopolymers are formed by alkali activation of an aluminosilicate and/or aluminophosphate material. The end-products are shaped as spheres, flakes, fibers, aggregates thereof or articles. Such products are formed at low temperatures; wherein forming includes processing using techniques such as spray drying, melt spinning, or blowing. The shaped geopolymeric particles and fibers have high chemical durability, high mechanical strength, application-targeted flowability and packing properties, and are specially suited for incorporating into composite materials, articles, and for use in cementitious, polymeric, paint, printing, adhesion and coating applications.

Abstract: An alkali resistant glass composition having improved durability to withstand highly alkali environments at elevated temperatures, such as curing of cementitious products in an autoclave, is conveniently formed from economical and abundant materials. The glass composition includes increased levels of calcium and iron, and relatively low levels of alkali metals, as compared to many other alkali resistant glass products, and comprises essentially of, by weight, >35% Si2O3, 1-25% CaO, 1-15% Fe2O3, 1-10% R2O, and an amount of Al2O3 such that the ratio of Si2O3:Al2O3 is greater than or equal to 1. Alkali resistance can be improved by forming a passivity layer on the surface of glass articles by treating the articles hydrothermally in a basic environment. Optionally zirconia and/or titania may be added to the composition to further improve alkali resistance.