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 cloth renowned for its very low thermal expansion coefficient and chemical inertness. The chemical makeup usually includes silica (SiO₂, 50-ninety%), alumina (Al₂O₃, https://www.pinlap.com/posts/35703