Chitin-Based Biorefinery-Derived Isosorbide Analogues as Rigid Building Blocks for Thermally Stable Polyacrylamides

High Resolution Image Download MS PowerPoint Slide Chitin is an abundant and renewable biomass resource with considerable potential as a feedstock for sustainable polymer materials. Here, we report a chitin-based biorefinery approach to isosorbide analogous acrylamide monomers and their radical polymerization into thermally stable polyacrylamides. An alcohol-free acrylamide monomer is successfully synthesized and polymerized under both redox-initiated and thermally initiated conditions, demonstrating robust polymerizability across diverse reaction protocols. The resulting polyacrylamide exhibits high thermal stability, with decomposition and glass transition temperatures comparable to those of common petroleum-derived engineering plastics. The polymer also shows a moderate yet meaningful fracture energy characteristic of glassy polymers. Mechanical analysis suggests that this energy dissipation is consistent with reversible interchain hydrogen-bonding interactions functioning as sacrificial bonds within the polymer physical network. In contrast, side-chain functionalization via phenyl carbamate formation markedly alters polymerization behavior and material properties, highlighting the critical roles of side-chain steric demand and intermolecular interactions in governing thermal stability and mechanical properties. Overall, this study demonstrates the potential of chitin-derived isosorbide analogues as sustainable, structurally rigid building blocks for high-performance polymer materials and provides molecular-level insights into the design of bio-based polymers with competitive thermal and mechanical properties.