Activity Monitoring for a Polymerization Catalyst System

Abstract

AbstractSummary: Catalyst systems for polymerization often exhibit variable and poorly controllable activity because of strong influences of trace components and catalyst preparation conditions. In cationic polymerizations in particular, determining catalytic activity and hence the amount of catalyst to be used is challenging. The assessment of a given initiator system typically requires testing it in polymerization reactions. Determining catalytic activity before using the initiator in a polymerization reaction is a desirable approach. This contribution describes the development of such an activity monitoring tool. In the first part, results from a fundamental characterization of the system diethylaluminum chloride/ethylaluminum dichloride/water by different NMR measurements and elemental analysis are reported. Structures characteristic of catalytically active systems are presented. The second part describes the application of transmission IR to the characterization of this system and the correlation of IR results to catalytic activity in dimerization and polymerization reactions. Implementation of the IR analysis as an on‐line measurement is demonstrated.