Small Molecule & Polymer Synthesis

Design and synthesis of new molecules and polymers with unique optoelectronic properties is an ongoing effort in the Reynolds group. Materials are designed and tuned by controlling the chemical structure to access a range optoelectronic properties. 

Schematic of how structure-property relationships are used to design and control the properties in electrochromic polymers.

In our group, organometallic coupling reactions are used as a way to make covalent aryl-aryl bonds for small molecules and polymers alike. The group has historically depended on Suzuki, Stille, and Grignard metathesis type polymerizations to achieve this goal, and remains used today.1,2,3 Direct heteroarylation polymerization (DHAP) has recently offered a fast, clean, and economic way to create many of the same materials.4

Schematic showing advantages of DHAP over more classical techniques in conjugated polymer synthesis.

Synthetic efforts are used to tune the properties of our materials. The figure below demonstrates an approach used to make electroactive polymers with discrete conjugation length. Using a conjugated monomer with a non-conjugated linker on both ends, a polycarbonate polymer is synthesized. This polymer has the mechanical properties of typical polycarbonates, but also offers electrochromic behavior.

Top: Polymerization of telechelic monomer to make a polycarbonte;4 a) free standing film of above polymer showing its ability to stretch due to non-conjugated linkers; b) spectroelectrochemistry demonstrating the electrochromic activity of the above polymer.

1.Kerszulis, J.A., Amb, C.M., Dyer, A.L., Reynolds, J.R. Macromolecules, 2014, 47, 5462-5469.
2.Argun, A.A., Berard, M., Aubert, P.-H., Reynolds, J.R. Adv. Mater. 2005, 17, 422-426.
3.Amb, C.M., Dyer, A.L., Reynolds, J.R. Chem. Mater. 2011, 23, 397-415.
4.Estrada, L.A.; Deininger, J.J.; Kamenov, G.D.; Reynolds, J.R. ACS Macro Lett, 2013, 2, 869-873.
5.Stalder, R.; Mavrinskiy, A.; Grand, C.; Imaram, W.; Angerhofer, A.; Pisula, W.; Mullen, K.; Reynolds, J.R. Polym. Chem. 2015, 6, 1230-1235.