PMSE 324 |
| Emulsion polymerizations are widely applicable in many industrial activities as they provide convenient synthetic routes to high molecular weight materials, high conversion and fast reaction rates in direct comparison with equivalent bulk reactions. The physical and material properties of the latexes yielded depend significantly on molecular characteristics such as molecular weights and particle size/uniformity. These characteristics are typically mechanistically, thermodynamically or kinetically controlled, and by obtaining concentration, kinetic and molecular weight information of the material formed, it is possible to understand and ultimately control these processes and therefore allow close tailoring of the materials yielded. Traditionally, this insight has required the analysis of multiple reactions with the systematic variation of key reaction variables. However, such investigations are time-consuming, tedious and describe only final products. This paper discusses the study of emulsion polymerizations, in or near real time, using new process monitoring and control (PMC) systems that utilize rapid online GPC or automatic online continuous monitoring (ACOMP) techniques. Continuously sampling directly from the reactor, these techniques generate molecular weight averages, percentage conversions, solution viscosity and chemical composition distributions as a function of reaction time. Additionally, particle size distribution analysis is used to determine both size and volume. These systems shorten the time required to fully elucidate these polymerization processes, as key information is obtained about all stages of the reaction. This greatly increases the efficiency of the investigation, allowing the possibility to alter the reaction conditions in real time to ensure that the reaction remains under control. Examples of various monitoring systems will be presented illustrating the technology. |
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Joint PMSE/POLY Poster Session
6:00 PM-8:00 PM, Tuesday, 12 September 2006 Moscone Center -- Hall D, Poster
Division of Polymeric Materials: Science & Engineering |