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Nicholas Rorrer

Manager and Senior Researcher - Polymer Science and Engineering

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Nic Rorrer is a senior researcher in the Biomaterials Development and Polymer Engineering group at NREL. His main research interests include the synthesis of performance-advantaged materials from biomass conversion, polymer characterization, polymer modeling, and recyclable-by-design thermosets.

Nic specializes in synthesizing polymers from biomass, which includes separating monomers from fermentation media, purifying the separated monomers, and subsequently polymerizing the monomers. Polyester, polyamides, and other polymers with a high degree of functionality are of interest due to the inherent functionality available to biomass. Performance advantages can manifest in manufacturing, operation, or end-of-life options.

Many monomers created by the biological conversion of biomass possess both carboxylic acid and olefinic moieties that make them ideal for use in unsaturated polyesters. The carboxylic acid moieties enable olefinic moieties to be placed into the backbone of unsaturated polyesters (UPEs), whereas olefinic moieties enable UPEs to be cross linked with reactive diluents. Nic is exploring these monomers, such as muconic acid, to see if they can enable performance-advantaged behavior over their petroleum counterparts. In the case of muconic acid, the two olefinic bonds provide rigidity to the UPEs and two sites for cross-linking, enabling UPEs with higher storage moduli and lower loss moduli. Additional work is dedicated to exploring reactive diluents to find alternatives to styrene.

Nic has been responsible for expanding NREL’s polymer synthesis and characterization laboratory. Due to the lab’s investments, researchers at NREL can characterize the size, shape, molecular weight, and thermomechanical properties of every polymer and plastic currently on the market, including but not limited to polyethylene, polypropylene, poly(ethylene terephthalate), and nylons. Such properties are necessary to compare new materials to those they could replace and understand their deconstruction.

Recently, work funded initially by NREL’s Laboratory Directed Research and Development program and subsequently by the U.S. Department of Energy’s Vehicles Technology Office has investigated methods of resigning today’s plastics recyclable by design. Part of this work is the redesign of resin for carbon-fiber-reinforced composites, which can, among other benefits, reduce the costs and emissions associated with carbon fiber use.

Research Interests

Biomass-enabled performance-advantaged products

Synthesis of polymers from renewable sources

Plastics recycling and upcycling

Carbon fiber composite redesign

Experimental determination of polymer rheology and modeling of polymer processing


Ph.D., Chemical and Biological Engineering, Colorado School of Mines, 2015

M.S., Chemical Engineering, Colorado School of Mines, 2013

B.S., Chemical Engineering, Virginia Polytechnic Institute and State University, 2011

Professional Experience

Senior Researcher, Biomaterials Development and Polymer Engineering, NREL (2020–present)

Researcher, Biomaterials Development and Polymer Engineering, NREL (2018–2020)

Postdoctoral Researcher, Polymer Engineering, NREL (2016–2018)

Graduate Intern, NREL (2015–2016)

Graduate Researcher, Colorado School of Mines (2011–2015)

Unit Operations Laboratory Instructor, Virginia Polytechnic Institute and State University (2011)

Undergraduate Research Associate, Virginia Polytechnic Institute and State University (2009–2011)

Featured Work

Bio-Based Polymers With Performance-Advantaged Properties, Nature Reviews Materials (2022)

Chemical and Biological Catalysis for Plastics Recycling and Upcycling, Nature Catalysis (2021)

Combining Reclaimed PET with Bio-based Monomers Enables Plastics Upcycling, Joule (2019)

Characterization and Engineering of a Plastic-Degrading Aromatic PolyesterasePNAS (2018)

Biomass-Derived Monomers for Performance-Differentiated Fiber Reinforced Polymer CompositesGreen Chemistry (2017)

Heterogeneous Diels-Alder Catalysis for Biomass-Derived Aromatic CompoundsGreen Chemistry (2017)

Renewable Unsaturated Polyesters from Muconic AcidACS Sustainable Chem. Eng. (2016)

Dynamic Free Energy Surfaces for Sodium Diffusion in Type II Silicon ClathratesPhysical Chemistry Chemical Physics (2016)

Cis,cis-Muconic Acid: Separation and Catalysis to Bio-Adipic Acid for Nylon 6,6 PolymerizationGreen Chemistry (2016)

Effects of Polydispersity on Confined Homopolymer melts: A Monte Carlo StudyThe Journal of Chemical Physics (2014)

Finding the Missing Physics: Mapping Polydispersity into Lattice-Based SimulationsMacromolecules (2014)

Molecular Scale Simulation of Homopolymer Wall SlipPhysical Review Letters (2013)

Parameter Free Prediction of Rheological Properties of Homopolymer Melts by Dynamic Monte Carlo SimulationMacromolecules (2012)

The Formation of Hydrophobic Films on Silica with AlcoholsColloids and Surfaces A: Physicochemical and Engineering Aspects (2010)


Renewable Resins and Unsaturated Polyesters and Methods of Making the Same, U.S. Patent Application No. 20170306085 (2017)

Awards and Honors

U.S. Department of Energy Office of Science Graduate Student Research Award (2015)

American Chemical Society Excellence in Polymer Graduate Research Award (2015)

Society of Rheology Student Poster Competition Winner (2014)

Colorado School of Mines Research Symposium Best Department Presentation (2014)