Flow Chemistry-Enabled Synthesis of Polymer Materials from Biomass-Derived Molecules for Enhanced Functionality

Abstract

The transition from fossil-derived feedstocks to renewable carbon resources demands not only alternative raw materials, but also reaction environments and processing strategies capable of transforming biomass into structurally defined, functional materials. This thesis addresses this challenge through the integrated development of solvent systems, reaction engineering strategies, and continuous-flow methodologies for the conversion of biomass-derived carbohydrates into polymer materials. The work begins with the microwave-assisted conversion of glucose to 5-hydroxymethylfurfural (5-HMF) in tetrabutylammonium-based deep eutectic solvent (DES) systems. Systematic optimization of solvent composition, temperature, catalyst loading, and reaction time enabled rapid and selective dehydration, achieving high yields within short reaction windows. Direct comparison with continuous-flow processing revealed fundamental differences in thermal control, solvent constraints, and residence-time effects, highlighting the interplay between reaction medium design and process configuration. Building on this foundation, the influence of DES composition, hydrogen bond acceptor (HBA) identity, and preparation strategy on glucose conversion was investigated experimentally. In addition, molecular dynamics simulations were employed to examine interaction patterns within the DES environment. The results indicate that catalytic performance is influenced not only by individual components, but by the overall solvent structure and interaction patterns within the medium. These findings establish a molecular-level framework for rational solvent design in biomass valorization. The final stage of the thesis delves in polymer production process in a continuous-flow tubular reactor. Fully aromatic polyamides derived from 2,5-furandicarboxylic acid (FDCA) and m-phenylenediamine were synthesized. The classical Yamazaki-Higashi phosphorylation route was translated to flow conditions. Furthermore, the yield was compared with a modified, greener tetrabutylammonium bromide/γ-valerolactone (TBAB/GVL) system. The study reveals the effect of solution stability, residence time, and temperature govern polymer formation under intensified flow conditions. Near-theoretical isolated yields were achieved within minutes, demonstrating the potential of microstructured flow reactors to synchronize activation and coupling steps in step-growth polymerization. Structural, thermal and molecular-weight analyses confirm the formation of rigid, thermally stable aromatic polyamides directly linked to biomass-derived monomers. Taken together, this thesis establishes a coherent pathway from carbohydrate conversion to continuous-flow polymer synthesis. It demonstrates that solvent structure, system composition, and reactor design are interdependent variables that determine efficiency, selectivity, and scalability. By integrating reaction engineering, molecular-level analysis, and materials synthesis, this work provides guiding principles for the design of flow-enabled, DES-based platforms for sustainable polymer production.