Indium-catalyzed Synthesis of Bio-based Functional Materials

Abstract: Bio-based polymers offer a promising route toward reducing reliance on petrochemical feedstocks, but their broader implementation requires efficient synthesis and control over material properties. In this work, indium catalysis is used to enable selective and efficient polymer synthesis across multiple bio-based starting materials. A cationic indium catalyst enables one-pot block copolymerization of methyl methacrylate and lactide, providing access to PMMA-b-PLA with tunable material properties. Indium catalysis is further applied to CO2/epoxide cycloaddition reactions using renewable substrates, including soybean oil and lignin. This catalytic approach enables more efficient access to cyclic carbonate precursors for subsequent non-isocyanate poly(hydroxyurethane) (NIPHU) synthesis. By tuning amine structure, functionality, composition, and hard-soft segment balance, the thermomechanical properties of the resulting NIPHU networks can be systematically controlled. Together, these studies integrate indium catalysis with molecular and network design to broaden the thermomechanical property window accessible to bio-based functional materials. Bio-based polymers offer a promising route toward reducing reliance on petrochemical feedstocks, but their broader implementation requires efficient synthesis and control over material properties. In this work, indium catalysis is used to enable selective and efficient polymer synthesis across multiple bio-based starting materials. A cationic indium catalyst enables one-pot block copolymerization of methyl methacrylate and lactide, providing access to PMMA-b-PLA with tunable material properties. Indium catalysis is further applied to CO2/epoxide cycloaddition reactions using renewable substrates, including soybean oil and lignin. This catalytic approach enables more efficient access to cyclic carbonate precursors for subsequent non-isocyanate poly(hydroxyurethane) (NIPHU) synthesis. By tuning amine structure, functionality, composition, and hard-soft segment balance, the thermomechanical properties of the resulting NIPHU networks can be systematically controlled. Together, these studies integrate indium catalysis with molecular and network design to broaden the thermomechanical property window accessible to bio-based functional materials.