One. Scientific Foundations of Hollow Glass Microspheres one.1 Composition and Microstructure 1.one.one Chemical Composition: Borosilicate Dominance Hollow glass microspheres (HGMs) are generally composed of borosilicate glass, a cloth renowned for its reduced thermal enlargement coefficient and chemical inertness. The chemical makeup generally consists of silica (SiO₂, fifty-ninety%)... https://500px.com/photo/1117584681/elementary-by-okok-okok