C. Schellenberg, K. Tauer, M. Antonietti
Why Reaction Calorimetry?
Since more than 30 years reaction calorimetry is a powerful tool to investigate the rate of chemical reactions. However, it is today not yet a very customary method to investigate the kinetics of heterophase polymerizations. We have running in our lab an isothermal 100 ml RM-2S (ChemiSens AB, Lund Sweden) combined heat flow and heat balance calorimeter and a 800 ml isoberibolic calorimeter (Prof. H.-U. Moritz). The figure shows two reaction rate profiles of emulsion polymerizations that deviate from the classical picture (yellow curve) which assumes a constant rate of polymerization during the second stage (particle growth period).
We use the reaction calorimeter also as a tool to carry out controlled multi-stage emulsion polymerizations (see next topic).
- H.-U. Moritz, in Polymer Reaction Engeneering, Ed. K.H. Reichert, W. Geiseler, VCH, Weinheim, 1989, 248
- A Calorimetric Study of Heterogeneous Styrene Polymerization: H. Björnberg, H. Nilsson, C. Silvergren, Thermochimica Acta 1984, 72, 239-244
- Details of the Emulsion Polymerization of Styrene Using a Reaction Calorimeter: L. Varela de la Rosa, E.D. Sudol, M.S. El-Aasser, A. Klein, Journal of Polymer Science: Part A: Polymer Chemistry 1996, 34, 461-473
- Evaluation of Heterophase Polymerization by Means of Reaction Calorimetry: K. Tauer, H. Müller, C. Schellenberg, L. Rosengarten, submitted to Colloid and Surfaces A: Physicochemical and Engeneering Aspects 1997