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Emergent Sequence Biasing in Step-Growth Copolymerization: Influence of Non-Bonded Interactions and Comonomer
Nhu Q Nguyen1, Ryan L Hamblin1, Kateri H DuBay1
1Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States.
The Journal of Physical Chemistry. B
|August 15, 2022
Summary
Controlling copolymer sequences is complex. This study shows how monomer attractions and activation energies together influence reaction kinetics and sequence formation, enabling advanced material design.
Area of Science:
- Polymer Chemistry
- Materials Science
- Chemical Engineering
Background:
- Copolymer properties depend on monomer sequence.
- Precise sequence control in copolymerization is challenging due to reaction kinetics and statistics.
- Mayo-Lewis reactivity ratios predict composition but not always sequence accurately.
Purpose of the Study:
- To investigate the combined effects of activation energies and non-bonded monomer attractions on copolymerization kinetics and sequence formation.
- To explore how these factors influence deviations from standard kinetics and sequence biasing.
- To understand the interplay between phase behavior and sequence development in step-growth copolymerization.
Main Methods:
- Utilized a generic, solution-based step-growth A,B-copolymerization model.
- Explored systems with varying activation energies and non-bonded attractions between monomers.
- Analyzed deviations from standard kinetics and emergent sequence heterogeneities.
Main Results:
- Differences in activation energies and non-bonded attractions significantly influence reaction kinetics and copolymer sequences.
- These effects can act synergistically or antagonistically, biasing sequence formation.
- Non-standard kinetics and long-range sequence biasing were observed, evolving over the reaction course.
Conclusions:
- Monomer interactions (activation energies and non-bonded attractions) are critical for controlling copolymer sequence and kinetics.
- Emergent phase behavior during polymerization can lead to significant sequence deviations.
- These findings offer insights for designing sequence-controlled polymers with tailored material properties.
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