Quantitative monitoring of polymerization reactions in real time has value in several areas: 1) In the R&D laboratory it can help achieve understanding of mechanisms and kinetics involved in the reactions, which can accelerate the pace of discovery and development of new polymeric materials, 2) It can help at the bench scale and pilot plant level to optimize reaction conditions and multi-stage processes, and 3) In a full feedback control system on industrial scale reactors it is projected to lead to accurate, optimized production of polymers in each batch, within specifications.
Our group has developed Automatic Continuous Online Monitoring of polymerization reactions (ACOMP) as a broadly applicable platform for many types of reactions and reactors. The basic principle is to continuously withdraw a very small stream from the reactor (typically 0.1ml/min) and dilute this with a selected solvent(s) to a level where absolute measurements are automatically and continuously made which yield the most important aspects of the reaction; comonomer conversion, weight average molecular weight and intrinsic viscosity, average composition and drift, residual monomer content, and rapid identification of unexpected phenomena such as microgelation, appearance of particulates, premature reaction termination, etc. The approach has been used to monitor a wide variety of reactions, including free radical copolymerization and controlled radical (ATRP, ROMP, NMP, RAFT) homopolymerization and multiblock and gradient copolymerization, heterogeneous phase reactions in emulsions and inverse emulstions, grafting, postpolymerization modifications, high temperature, pressurized, high viscosity reactions, and others.
The first ACOMP publication was in 1998 and over 40 more have since followed. A patent estate owned by Tulane University has grown over the years as the platform has broadened and deepened. A new spinoff company from Tulane, Advanced Polymer Monitoring Technologies, Inc. (New Orleans) has exclusive license to these patents and is currently in the process of commercializing both R&D laboratory ACOMP instrumentation, and ACOMP units for full scale industrial reactors via Joint Development Agreements with companies.
This talk will briefly review the principles and basics of ACOMP theory and practice and then survey some of the accumulated results in various application, including the extension of ACOMP to a ‘second generation’ method capable of monitoring the onset and evolution of polymer stimuli responsive behavior during synthesis (‘smart’ polymers). Progress concerning the ongoing transfer of ACOMP from the R&D lab to the industrial reactor environment will also be reported.
Some other complimentary methods developed in our group will also be briefly presented, including high throughput Simultaneous Multiple Sample Light Scattering (SMSLS), and Automatic Continuous Mixing (ACM), including applications in therapeutic proteins for the pharmaceutical industry.