The majority of plastics we use in our day-to-day lives are sourced from petroleum, which is both non-renewable and non-sustainable. As a contributing group in the Center for Sustainable Polymers (CSP), we strive to develop monomers and polymers from sustainable resources. Research projects in this area are highly collaborative with other research groups in the Center.

Sustainable polymer projects in our group are natural extensions of our group’s other projects. Often in our group, drug delivery vehicles employ carbohydrates in their polymer structures. Carbohydrates represent a key feedstock for green materials development, as they are the most widely available renewable resource. The sustainable polymers we develop are designed to exhibit low toxicity while being biodegradable; key characteristics of biomaterials and desired properties for sustainable plastics. Consequently, the understanding of sustainable polymers is central towards the development of biomaterials that will enable our group to enter other therapeutic areas.

We are dedicated towards understanding the synthesis, development, and properties of sustainable polymers.

Featured Projects – Sustainable Polymers

Leon TOC With the aim of preparing sustainable and degradable polymers from sugar-derived precursors, a family of five poly(ester-thioethers) were synthesized by photoinitiated thiol–ene polymerization of monomers incorporating D-glucaro-1,4:6,3-dilactone (GDL). Various dithiols were used to produce linear poly(ester-thioethers) of glucarodilactone 10-undecenoate (GDLU) to probe the effect of the dithiols on the observed mechanical performance and degradability. The samples exhibited glass transition (Tg) values from −8.7 to 19 °C. The polymers with the simplest dithiols, 1,2-ethanedithiol (EtDT) and 3,6-dioxa-1,8-octane-dithiol (DODT), were found to exhibit crystallinity, while the more structurally complex and rigid dithiol structures were found to produce amorphous materials. Due to the GDL units in the polymers, rapid degradation under basic aqueous conditions and stability in acidic and neutral conditions were observed. Tensile testing of these materials showed robust mechanical properties, including tunable moduli (0.011 to 0.29 GPa), strength (21 to 42 MPa), and ductility (410 to 590%). Reference: Leon M. Lillie, William B. Tolman, Theresa M. Reineke "Degradable and Renewably-sourced Poly(ester-thioethers) by Photo-initiated Thiol-ene Polymerization", Polym. Chem. 2018, 9, 3272–3278.
We have recently been working on developing sustainable epoxy resin thermosets from carbohydrates, such as trehalose and cyclodextrin, and soybean oil. The resulting resins have been found to be stable to heat and neutral and acidic conditions, while demonstrating the ability to degrade under basic conditions. Notably, the mechanical properties of these resins can be tuned by varying the carbohydrate and the composition of the feedstock. These resins have also shown potential for use in medical applications due to their ability to either promote or prevent cell adhesion and growth. A manuscript based on this work was recently submitted for publication.