The importance of the maximum in the heat of reaction or rate of polymerization curve (R p max ) is defined by describing the main processes that occur around this maximum. The relevance of knowing when it occurs is illustrated by experiments performed in an automated reaction calorimeter. The effec
Details of the emulsion polymerization of styrene using a reaction calorimeter
โ Scribed by L. Varela de la Rosa; E. D. Sudol; M. S. El-Aasser; A. Klein
- Publisher
- John Wiley and Sons
- Year
- 1996
- Tongue
- English
- Weight
- 1022 KB
- Volume
- 34
- Category
- Article
- ISSN
- 0887-624X
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โฆ Synopsis
An automated reaction calorimeter was used to directly monitor the rate of emulsion polymerization of styrene using different emulsifier (sodium lauryl sulfate) and initiator (potassium persulfate) concentrations. By using this technique in conjunction with off-line measurements of the evolution of the particle size distributions, important details of the process were observed. The classical constant rate period (Interval 11) often reported for the batch emulsion polymerization of styrene was not seen in this work. Instead, the experimental results suggest that the end of nucleation and the disappearance of monomer droplets take place at approximately the same conversion (36-40%). From the polymerization rate data, important parameters such as the monomer concentration in the polymer particles and the average number of radicals per particle were calculated.
๐ SIMILAR VOLUMES
The batch emulsion polymerization of styrene was studied as a function of the initial monomer charge. The emulsifier (sodium lauryl sulfate) concentration was fixed at a level in excess of its critical micelle concentration (cmc). The mechanism of the polymerization was examined through data obtaine
Emulsion polymerizations of styrene were performed with different emulsifier and initiator concentrations, using an automated reaction calorimeter. The reactions were compared to the classical description of the emulsion polymerization process in terms of the shape of the rate of polymerization curv