1. Scientific Foundations of Hollow Glass Microspheres 1.one Composition and Microstructure 1.1.one Chemical Composition: Borosilicate Dominance Hollow glass microspheres (HGMs) are largely made up of borosilicate glass, a fabric renowned for its low thermal growth coefficient and chemical inertness. The chemical make-up generally consists of silica (SiO₂, fifty-ninety%), alumina (Al₂O₃, http://myworldgo.com/profile/okok0972/action_id/3410030/show_comments/1