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Sara Orski (Fed)

Research Chemist, Project Leader - Macromolecular Architectures

Research Interests:

My project focuses on the design, synthesis, and characterization of model thermoplastics, with systematic variation of polymer sequence, chemistry, and architectures to generate libraries of quantitative structure-property-performance relationships (validated by multiple measurement methods).

Applications: polyolefin standard reference material testing and development, improved polymer separation methods

The project aims to develop methodologies to quantitatively identify and characterize molar mass, branching content, and chemical composition of degraded of plastics from recovered ocean debris and real-world and laboratory experiments.

Applications: evaluating new degradation/recycling catalysts, informing the strategic design of laboratory degradation

Research Interests:

  • polymer synthesis 
  • polymer degradation and recycling
  • size-exclusion chromatography (ambient and high temperature)
  • next-generation standards development and next-generation protein sequencing
  • quantitative structure-property-performance relationships

ProfessionaI Background Summary: I am a polymer chemist with strong background in polymer synthesis and characterization methods. Currently, I lead the Macromolecular Architectures project, which focuses on synthetic approaches to next-generation reference materials and families of systematically varied polymer architectures and functionalities to better understand structure-property-performance relationships.  

Additionally, I have direct experience with post-polymerization modification, surface functionalization, and surface adsorption monitoring. 

I am always interested in collaborative projects involving communication with scientists and other professionals across disciplines.

Google Scholar: publications and citations

LinkedIn: profession network and background

Research Opportunities

National Research Council (NRC) Research Associates Program (RAP)

  • Design, Characterization, and Modeling of Sequence Controlled Polymers:  Development of quantitative structure-property relationships for polymers has been largely limited due to the inability to systematically control polymer sequence especially under real-world conditions where process history, crystallization, and degradation cannot be neglected.  We are interested in addressing these challenges through the integration of synthesis, simulation, and polymer metrology for sequence-controlled polymers. Rational design of model polymer systems with varying degrees of sequence control, including well-defined, periodic, gradient, and block monomer sequences achieved through controlled polymerization. 
  • Physical Models and Characterization of Olefinic CopolymersManufacturability and life cycle assessments of polyolefin copolymers are hampered by multiscale characterization challenges. From molecular composition and distributions, to solution and bulk processing behavior, there are numerous limitations in the current technologies for characterizing these complex yet ubiquitous semi-crystalline polymers. Our research efforts focus on advances in design, synthesis, or processing of advanced materials from these polymers, or the end of life challenges which exist for disposal, environmental impact assessment, or recycling of polyolefins.
  • Model Polymer Gels and Networks for Rational Sustainable Design: Understanding the structure and mechanical properties of polymer networks is critical to a variety of soft material applications ranging from sustainability to impact mitigation. The polymer chemistry and structure of these entangled materials are essential to defining their mechanical and (re)use properties, yet the specific relationships are not well established. We are interested in studying the structure and mechanical properties of polymer networks with defined molecular topologies (functionality, branching, and molecular mass distribution), as well as dynamic or reversible polymer chemistry that introduce labile sites vulnerable to catalysis and stimuli-responsive chain cleavage. 


The 2022 Charles L. Gordon Award, The Chemical Society of Washington


Correlating Near-Infrared Spectra to Bulk Properties in Polyolefins

Bradley Sutliff, Shailja Goyal, Tyler Martin, Peter Beaucage, Debra Audus, Sara Orski
The industry standard for sorting plastic wastes is near-infrared (NIR) spectroscopy, which offers rapid and nondestructive identification of various plastics

Time-gated Raman spectroscopy of recovered plastics

Anthony Kotula, Sara Orski, Kayla Brignac, Jennifer Lynch, Bryan Heilala
Raman spectroscopy is a powerful non-destructive technique for the identification and characterization of plastics. The technique often has limited use due to
Created October 23, 2018, Updated March 31, 2023