1. Scientific Foundations of Hollow Glass Microspheres one.1 Composition and Microstructure 1.one.1 Chemical Composition: Borosilicate Dominance Hollow glass microspheres (HGMs) are primarily made up of borosilicate glass, a material renowned for its lower thermal expansion coefficient and chemical inertness. The chemical makeup ordinarily incorporates silica (SiO₂, 50-90%), alumina (... https://www.bib.az/post/229332_elementary-substance-is-a-pure-chemical-substance-that-consists-of-atoms-belongi.html