Molecular Weight Distribution Engineering

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We wrote a software program in collaboration with Artem Avetisyan to design molecular weight distributions in arbitrary polymerization processes. Our goal was to have a procedure that is chemistry agnostic, simple to use, and predictive of the molecular weight distribution of the final material. To implement our method, these are the required pieces:

  • A solution polymerization chemistry that provides increasing molecular weights over time, preferably with low dispersities (living polymerizations work best)
  • A quenching methodology that can quickly and irreversibly quench the polymerization and prevents any side reactions such as transesterification
  • A syringe pump or other pump that can transfer fluid from one vessel to another and can be computer controlled

Once these requirements are fulfilled, the software can be used by first collecting polymerization data in a measurement run. During this measurement run, identical conditions to the design run (when the custom molecular weight distribution is synthesized) should be used. Good reproducibility is very important here. The data collected should be molecular weight distributions with time as measured by GPC. These molecular weight distributions should span molecular weights across the space within which the design molecular weight distribution spans. These aliquots along with the design molecular weight distribution and the desired final volume of polymerization solution can be run through our software to calculate the flow rate that best matches target distribution. More information on this methodology and our results can be found in our publication.

MWD Design Software