Contribution of Raman Spectroscopy to In Situ Monitoring of a High-Impact Polystyrene Process
Résumé
A high-impact polystyrene (HIPS) process has been studied using Raman spectroscopy as a monitoring technique for the first time. Thermal polymerization of styrene was carried out in the presence of polybutadiene. A Raman probe with a short focal distance, immersed into the reaction medium, allowed in situ monitoring of styrene consumption over the whole reaction progress. A Raman probe with a long focal distance set outside the glass reactor was applied to detect phase separation and phase inversion. Finally, coupling Raman spectroscopy and flow rheometry into a single experimental setup allowed in situ monitoring of both phase behavior and viscosity variation during the HIPS process. Results obtained from Raman spectroscopy were correlated to those from laser granulometry and gravimetric analysis.