Synthesis and characterization of sustainable polymeric materials from biomass-derived levoglucosan

Abstract

The world is at a tipping point in the current Plastic Age; we cannot possibly eliminate plastics from modern society, but at the same time, we can no longer turn a blind eye to their negative environmental impact. To address this planetary boundary threat, we must develop sustainable polymeric materials. Levoglucosan – an anhydro sugar obtained directly from the fast pyrolysis of cellulosic biomass – is a promising renewable platform chemical for sustainable polymers. The work in this thesis utilizes levoglucosan for the synthesis and characterization of different types of unexplored sustainable polymeric materials with versatile properties and applications. The first area of research describes the synthesis of 1,6-α linked functional stereoregular polysaccharides from levoglucosan via cationic ring-opening polymerization and post polymerization modification. Combined experimental and computational studies were used to provide key kinetic, thermodynamic, and mechanistic insights into the polymerization of levoglucosan derivatives with low toxicity metal triflates. The second area of research expands the usage of levoglucosan to crosslinked networks by synthesizing a family of biobased thermosets from triallyl levoglucosan and multifunctional thiols via thiol–ene click reaction. The structure–property–degradability relationship of these tunable thermosets was elucidated. The suitability of these levoglucosan-based resins for 3D printing was demonstrated using Direct-Ink-Write to create degradable 3D printed parts for sustainable rapid prototyping and mass production applications. Finally, the third area of research details the synthesis of unique sugar-based copolymers through cationic ring-opening copolymerization of levoglucosan and ε-Caprolactone. These monomers were polymerized to obtain functional copolymers with a gradient architecture and a wide range of copolymer composition.