Upcycling Silica Soot Waste into Transparent Silica Components Using Interparticle Photo-Cross-Linkable Slurries

Abstract

Silica soot waste was successfully upcycled into complex structured transparent silica components by designing interparticle photo-cross-linkable slurry which is composed of small amounts of multifunctional acrylate, photo radical initiator, and silica soot modified by functionalized polyethyleneimine (PEI). After optimizing the additive contents of functionalized PEI and the ball milling time of the slurries to prepare low viscous slurries with improved silica soot dispersion, sintering conditions to achieve full densification of the photo-cured bodies was investigated. Sintering of ‍photo-cured bodies, which was prepared from 32 vol% silica soot slurries stabilized by 1.1 mg/m² of functionalized PEI, at 1350°C for 60 min resulted in successful densification to a transparent silica glass component.