Department of Chemistry
Massachusetts Institute of Technology (MIT)
Chemical Tools for Manipulating the Topology of Polymer Networks
All polymer networks have cyclic molecular topologies that critically impact their bulk properties. Nevertheless, these cyclic topologies have historically been difficult to quantify and control. Informed by classical crossover experiments, the Johnson Group has developed experimental methods for the precise counting of cyclic topologies (loops) of various order in polymer networks. These studies have enabled new theoretical advances pertaining to elasticity and the gel point, and have inspired new designs for stimuli-responsive materials.
Dr. Johnson conducted undergraduate research with Professor Karen L. Wooley at Washington University in
St. Louis, where he received a BS in Biomedical Engineering with a second major in Chemistry. He then
moved to Columbia University, where he received a PhD in Chemistry under the mentorship of Professor
Nicholas J. Turro. Later, he held a Beckman Postdoctoral Fellowship at California Institute of Technology under the guidance of Professors David A. Tirrell and Robert H. Grubbs. Johnson is now an Associate Professor of Chemistry at MIT, where he has been since July, 2011. He is also a member of the MIT Program for Polymers and Soft Matter (PPSM), as well as the Koch Institute for Integrative Cancer Research.
Dr. Johnson received a 2019 ACS Cope Scholar Award, the 2018 Macromolecules-Biomacromolecules Young
Investigator Award, the 2018 Nobel Laureate Signature Award for Graduate Education, a Sloan Research Fellowship, the Air Force Young Investigator Award, the Thieme Journal Award for Young Faculty, the DuPont Young Professor Award, the 3M Non-Tenured Faculty Award, and an NSF CAREER Award. In recognition of his teaching, he was awarded the 2018 MIT School of Science Undergraduate Teaching Prize. The Johnson Research Group is focused on the development of methods and strategies for macromolecular synthesis and surface functionalization.