Characterising different molecular landscapes in dynamic covalent networks

Area of Science:

• Polymer Chemistry
• Materials Science
• Chemical Engineering

Background:

• Dynamic covalent networks (DCNs) offer molecular control over macroscopic properties by linking thermal behavior to chemical thermodynamics and kinetics.
• Current methods lack the ability to analyze local variations in reactivity due to reactants, catalysts, or additives.
• Understanding these local effects is crucial for precise material engineering.

Purpose of the Study:

• To develop a rheological paradigm for correlating polymer segment composition with network rearrangement rates.
• To enable quantitative analysis of local chemical reactivity influences on DCN behavior.
• To facilitate the design of functional, rapidly reprocessable materials.

Main Methods:

• Utilized a generalized Maxwell model to individually quantify the dynamic behavior of different reactive segments.
• Employed Eyring and Van 't Hoff analysis combined with statistical modeling and rheology measurements.
• Correlated bond catalysis and dissociation with structural changes.

Main Results:

• Successfully separated and quantified the dynamic contributions of individual reactive segments within DCNs.
• Precisely measured viscosity changes, allowing for accurate comparisons between different DCN materials (e.g., vitrimers, dissociative networks).
• Demonstrated the method's capability to analyze various rate-enhancing effects.

Conclusions:

• The developed rheological paradigm accurately quantifies the relationship between DCN composition and network dynamics.
• This method allows for the prediction and engineering of material properties for enhanced processability and functionality.
• It provides a powerful tool for analyzing and designing advanced dynamic covalent network materials.