Chemical, Macromolecular, and Thermal Characterization of Polymers Recovered from the Marine Environment

Abstract

In order to understand the extent, ecological effects, and lifetimes of plastic debris in the ocean and on Earth’s beaches, it is necessary to quantify how these synthetic polymers degrade under natural environmental conditions and the variability in degradation conditions among materials of different sizes, surfaces areas, differing commercial compositions and formulations. This presentation will highlight systematic methods to identify and characterize chemical composition, thermal, and macromolecular properties of marine plastic debris, recovered from both from the digestive tract of sea turtles and collected from Kaupo Beach in Oahu, Hawaii. Bulk and depth profiling measurements of discarded polyolefins were conducted to identify the polymer and determine the extent of degradation. Quantitative measurements verify that selected polymer fragments degrade predominately through chain scission and comparative measurements across a series of recovered plastics will be compared to discuss how sampling methods for marine debris, using alternate techniques of identification, and establishing quantitative degradation measurements will be needed to (ultimately) develop predictive quantitative models of polymer degradation pathways and kinetics in marine ecosystems.

About the Speaker

Sara V. Orski is a research chemist and project leader in the Materials Science and Engineering Division at The National Institute of Standards and Technology (NIST). Her current research team focuses on using design, synthesis, and characterization of recovered and model materials to quantify the effect of macromolecular chemistry and architecture on dilute solution, bulk material properties, and degradation. Dr. Orski earned a B.S. in Chemistry from The College of William and Mary and a Ph.D. in Chemistry from The University of Georgia studying functional polymer brush thin films for sensor applications. She joined NIST as an NRC Postdoctoral Fellow studying stability of enzymatic catalysts on polymeric supports for greener polymer catalysis. She is active in technical programming and environmental issues within the American Chemical Society (ACS), serving as a co- programming chair within the Division of Polymer Chemistry, is an associate member of ACS Committee on Environmental Improvements (CEI), and is a Councilor in her local ACS section, The Chemical Society of Washington.