1. Scientific Foundations Of Hollow Glass Microspheres 1.one Composition and Microstructure one.1.1 Chemical Composition: Borosilicate Dominance Hollow glass microspheres (HGMs) are mostly made up of borosilicate glass, a material renowned for its very low thermal expansion coefficient and chemical inertness. The chemical makeup typically features silica (SiO₂, 50-90%), alumina (Al₂O₃, https://expressafrica.net/post/401198_sulfide-powder-refers-to-the-chemical-compounds-powder-with-large-families-of-in.html