One. Scientific Foundations of Hollow Glass Microspheres one.1 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 small thermal expansion coefficient and chemical inertness. The chemical make-up usually includes silica (SiO₂, 50-ninety%), alumina (Al₂... https://www.pinlap.com/posts/35708