Date/Time
Date(s) - 13/05/2021
1:30 pm - 2:30 pm

Prof. Karen L. Wooley, Texas A&M University,College Station, Texas, USA

Title:  “SYNTHETIC STRATEGIES BY WHICH TO AFFORD NATURAL PRODUCT–BASED POLYMER MATERIALS: IMPACTS ON SUSTAINABILITY, LIFE, HEALTH AND THE ENVIRONMENT” 

Date:                    Thursday, May 13^th,2021 

Time:                   1:30 p.m.  

Zoomlink:    available from macchem@mcmaster.ca

Host:                    Dr. Alex Adronov 

Abstract:

A primaryinterest in the Wooley laboratory is the production of functional polymers fromrenewable sources that are capable of reverting to those natural products oncetheir purpose has been served. A long-standing focus has been the developmentof synthetic methodologies that transform sugars, amino acids and other naturalproducts into polymer materials. This approach allows for the production offunctional polymers from renewable sources that are capable of reverting tothose natural products once their purpose has been served (as is illustrated onthe left side of the diagram below). This holistic life cycle approach is ofimportance from the perspectives of sustainable sourcing of materialsfeedstocks, while creating mechanisms for breakdown of the polymer materialsafter useful lifetime is complete, and providing for biological and environmentalresorption of breakdown products. The overall process impacts the need toaddress the increasing accumulation and associated hazards of plastic pollutionfrom the environmental persistence of non- degradable, petrochemically-sourcedpolymer systems. Moreover, inherent diversities of natural products provideopportunities to expand the scopes, complexities and properties of polymers, byutilizing fundamental organic chemistry approaches.

Target materials are designed for potential applications in diverse areas. Forinstance, we have produced amphiphilic block polymers that undergosupramolecular assembly in water to afford well-defined nanoscopic particles(diagram below, upper section (a)). By tuning the composition, structure andmorphology, we are able to build functional nanoparticles that demonstrateefficacy as therapeutic nanomedicines for treatment of recurrent urinary tractinfections (a1) and lung infections (a2), and we’re working toward their use inthe treatment of osteosarcoma lung metastases. When the amphiphilic blockpolymers are co-assembled with iron oxide nanoparticles,magnetically-responsive organic-inorganic composite nanosystems result, whichare able to perform as environmental remediation agents that capture ten timestheir mass in crude oil from contaminated water (work that began following theDeep Water Horizon oil spill a decade ago). Macroscopic forms (diagram, lowersection (b)) of our Sugar PlasticsTM were initially studied with an aim towardtheir use in orthopedic applications (b1), when we identified that specificchemical compositions containing nanoscopic and microscopic porosities operateas bioresorbable hemostatic wound dressing materials (b2). We’re currentlyworking with Teysha Technologies, LTD to advance these polymer materials forcommercial translation as naturally-degradable plastic packaging to address thegrowing plastics pollution crisis (b3). Most recently, in response toincreasing challenges with climate change, we’ve designed analogs to exhibit propertiesthat allow them to serve as superabsorbent degradable polymers to captureexcessive liquid water, thereby preventing flooding, and later degrade torelease the natural building blocks and water, thereby mediating drought andpromoting crop growth (work that began from struggling through Hurricane Harveyin 2017).

This presentation will highlight synthetic strategies for the development ofpolymers, block polymers and crosslinked network materials, which can beproduced by relatively simple approaches from glucose and can be made toexhibit a range of properties. Target materials are designed for potentialapplications in diverse areas, from medicine, e.g., as nanotherapeutics orbioresorbable hemostatic agents, to the environment, e.g., as pollutant captureagents, climate resilient hydrogel materials or naturally-degradable plastics.Examples will highlight contributions that polymer chemistry can make towardbulk technological materials that are capable of impacting global needs, suchas water-food-energy-health, and the grand challenges that must be solved inthe coming decade.