Barnes wins grant to expand architectures of interlocking molecular rings

Jonathan Barnes, assistant professor in the Department of Chemistry, won a $450,000 grant from the National Science Foundation to investigate and expand efficient methods for synthesizing catenane-based polymers and networked materials.

Barnes

Catenanes are mechanically interlocked molecules consisting of two or more rings, which allows them – and the material in which they’re incorporated – enough freedom of movement to do things like rotate, stretch, and compress when subjected to external forces. Catenanes’ unique interlocking ring structure may allow chemists to use them in creating next-generation materials unlike those achievable with traditional polymers.

Laying the foundation for future research and development, researchers in Barnes’ lab are making new catenane architectures, with a particular focus on extending the number of rings that can be mechanically interlocked, while also installing polymerizable groups at the end of each chain. These terminal groups would allow Barnes to combine individual catenane chains into long linear polycatenanes and larger catenane-based networks.

“We hope to scale the amount of material that can be synthesized so we have enough to test in materials,” Barnes said. “This study is fundamentally important because it should allow us, for the first time, to make enough of these architectures to characterize basic thermal properties, like glass transition temperatures and the molecular weight threshold for polymer entanglement.”

With this work, Barnes and his research group are bridging the synthetic gap between small chains and polycatenanes while also addressing scalability issues. By removing these limitations, they set the stage for developing new topologically controlled polymers and materials, including rubber-like materials and plastics with improved stretchability and greater capacity to dissipate forces.