Online Polymerization Monitoring & Control

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Automatic Continuous Online Monitoring of Polymerization (ACOMP) Reactions

Introduction

The PL-PMC (Polymerization Monitoring and Control) is a sophisticated suite of instrumentation, coupled with control and analysis software for the online monitoring of polymerization reactions. The system allows the rapid, automated and accurate monitoring of key reaction parameters in near real time and can be configured for use within both the academic and commercial arenas, allowing the versatility to make a significant impact across polymer research and development, production monitoring and process control.

The PL-PMC system enables direct investigation of important aspects of polymerization processes, including the real-time calculation of molecular weight averages and distributions, the effect of changes in reactor conditions and design, the effect of initiator selection and the monomer consumption and polymer formation kinetics.

Key Benefits

• Automated analysis of polymerization reactions continuously from initiation to completion in one shot, generating much more information than can be obtained from single offline or bulk property measurements.
• Enables a rapid assessment of polymerization progress by generating real time data.
• Improves process economics, product yield and quality by eliminating batch failure.
• Maximizes staff efficiency by allowing totally automated and unsupervised operation.
• Minimizes reactor downtime.
• Promotes proactive control – move the lab to the sample.
• Enables the possibility to quench a reaction if a sudden unexpected exotherm occurs.
• Enables the prediction of undesirable effects such as the rapid onset of gelation

Multiple Detection Philosophies for Information Rich Analyses

The system couples continuous sampling direct from the reactor with chromatographic monitoring (gel permeation chromatography (GPC), flow injection analysis (FIA) and hydrodynamic chromatography (HDC)) and Automatic Continuous Monitoring of Polymerization (ACOMP*) monitoring.

These two analysis philosophies can be integrated individually, or coupled to provide information rich detection (IRD) solutions for the most complex of laboratory needs. Information rich detectors have the ability to provide multi-dimensional layers of data that go beyond the mere detection of a compound by producing highly detailed molecular weight, structural and compositional molecular information in real time.

The IRD approach can yield the following key reaction information:

• Molecular Weight Averages and Distributions
• Monomer Conversion
• Intrinsic/Solution/Reduced Viscosity
• % Composition of Copolymer
• Radius of Gyration
• Bulk Molecular Weights
• Degrees of Branching
• Particle Size Averages and Distributions

* Manufactured by Polymer Laboratories under license from Tulane University, New Orleans.

PL-PMC Instrumentation Design

The PL-PMC operates through the careful integration of multiple components to provide seamless operation and consistent results.

Deriving polymerization data involves a four-stage process:

Schematic of a PL-PMC System set up for both continuous and chromatographic polymerization monitoring

Real-time Management of Polymerization Reactions

Polymerization reactions are controlled by several closely related factors such as the reaction mechanism, the thermodynamics and the kinetics of the process. These parameters vary during the reaction as monomer is depleted and polymer formed. Obtaining concentration, kinetic and molecular weight information during polymerization is critical to understanding and ultimately controlling these processes. Traditionally, this requires the analysis of products of multiple reactions in which key parameters are systematically varied. Such investigations are time consuming and tedious and only describe the final product, by which time it is too late to change the reaction conditions to improve the outcome. The fast, efficient and routine monitoring of polymerization processes has long been a goal for polymer chemists. Now, using the PL-PMC system, you can access information on these changes of state during the polymerization reaction. This allows rapid monitoring of processes and fast and efficient control of reaction conditions, moving towards proactive control by taking the lab to the sample, rather than assessing the finished product.

Polymerization, monitoring and control is key to real time management of polymer development.