Photo-redox mediated ring-opening metathesis polymerization (photo-ROMP) is an emerging ROMP technique that uses an organic redox mediator and a vinyl ether initiator, in contrast to metal-based initiators traditionally used in ROMP. The reversibility of the redox-mediated initiation and propagation steps enable spatiotemporal control over the polymerization. Herein, we explore a simple, inexpensive means of controlling molecular weight, using alpha olefins as chain transfer agents. This method enables access to low molecular weight oligomers, and molecular weights between 1 and 30 kDa can be targeted simply by altering the stoichiometry of the reaction. This method of molecular weight control was then used to synthesize a functionalized norbornene copolymer in a range of molecular weights for specific materials applications.
Congrats to Bo and Johanna on their recent paper in Polymer Chemistry!
The collaborative projective with Prof. Nick Boechler’s team demonstrates how micro- and macroscale architecture influences mechanochemical activation in thermoplastic and elastomer materials. You can read the paper at https://doi.org/10.1039/C9PY01875A.
Reduced Strain Mechanochemical Activation Onset in Microstructured Materials
In this study, we show that mechanochemical activation in responsive materials with designed, periodic microstructures can be achieved at lower applied strains than their bulk counterparts. Furthermore, by characterizing two responsive polymeric materials, we have developed a computational model capable of quantitatively predicting mechanochemical activation in geometrically complex structures.
Huge congrats to Brock on his Mater. Chem. Front. paper!
Brock is the first author on a Mater. Chem. Front. publication that showcases a new class of strained macrocycle that performs well in ROMP. The paper can be found here: https://pubs.rsc.org/en/content/articlelanding/2020/qm/c9qm00604d#!divAbstract
Ring-opening metathesis polymerization of a strained stilbene-based macrocyclic monomer
We report the synthesis of a new class of strained macrocycle that performs well in ring-opening metathesis polymerization (ROMP). The polymerization displays chain growth characteristics with evidence of secondary metathesis in the form of chain transfer. The unique structure enables access to stilbene-based polymers that are traditionally prepared via uncontrolled polymerizations.
The Group warmly welcomes Kyle, Meg, and Olivia!
The Boydston Group is excited to have our newest graduate students on board! We know they’re going to do great things! 🙂
Congrats to Vinnie on his JACS paper!!
This project was led by the Barner-Kowollik group and centers on the discovery that disparate monomer classes, norbornene and methacrylates, can be copolymerized in a photomediated process. The paper can be found here: https://pubs.acs.org/doi/abs/10.1021/jacs.9b09025
Hybrid Photo-induced Copolymerization of Ring-Strained and Vinyl Monomers Utilizing Metal-Free Ring-Opening Metathesis Polymerization Conditions
We introduce the hybrid copolymerization of two disparate monomer classes (vinyl monomers and ring-strained cyclic olefins) via living photopolymerization. The living character of the polymerization technique (metal-free photo-ROMP) is demonstrated by consecutive chain-extensions. Further, we propose a mechanism for the copolymerization and analyze the copolymer structure in detail by high-resolution mass spectrometry.
Welcome, Dr. Evan Sherbrook!
The Boydston group proudly introduces Dr. Evan Sherbrook as our newest postdosctocal researcher!
Welcome to the group, Danny!
We are happy to welcome Danny Lee to the Boydston Group as a post-baccalaureate researcher!