Polyacrylate Vitrimer Network via In Situ Isocyanide Copolymerization: Synthesis and Molecular Dynamics.

Area of Science:

• Polymer Chemistry
• Materials Science
• Sustainable Materials

Background:

• Plastic pollution necessitates sustainable materials with effective end-of-life management.
• Vitrimers offer a promising solution by combining thermoset durability with recyclability through dynamic covalent bonds.

Purpose of the Study:

• To develop a novel, one-step photocopolymerization method for creating vitrimers.
• To introduce vinylogous urethane-like linkages into polyacrylate networks using isocyanide cross-linkers.
• To investigate the reprocessability, mechanical properties, and charge transport mechanisms of the resulting vitrimers.

Main Methods:

• One-step photocopolymerization utilizing multifunctional isocyanides.
• Mechanical testing to assess performance after multiple processing cycles.
• Broadband dielectric spectroscopy (BDS) to analyze bond-exchange dynamics and topological rearrangements.

Main Results:

• The synthesized vitrimers exhibited good reprocessability, retaining mechanical performance over three cycles.
• BDS revealed a transition from kink-like to Arrhenius behavior in relaxation times upon annealing, indicating defect healing.
• A correlation between bond-exchange relaxation and electrical conductivity confirmed the former as the primary charge transport mechanism.

Conclusions:

• A facile photocopolymerization route to sustainable vitrimers was established.
• The study provides a mechanistic understanding of charge transport and defect healing in vitrimers.
• Findings offer new avenues for designing advanced sustainable dielectric materials.