Hana Kaehr
Pronouns: she/her/hers
Research Mentor(s): Richard Laine
Research Mentor School/College/Department: Materials Science and Engineering / Engineering
Program: UROPF
Session: Session 6 (3:40pm – 4:30pm)
Authors: Hana Kaehr, Zijing Zhang, Sabrina Huynh, Richard Laine
Abstract
In polymers, there exists conjugated properties. We are studying polymers which are not supposed to exhibit conjugation based on previous knowledge of how conjugation works. However, some of these polymers do exhibit conjugation, and can be used for semiconductor applications. Expanding on the existing knowledge that double decker (DD) copolymers and ladder copolymers show conjugation, we are studying disiloxane copolymers, which are smaller units of the DD and ladder copolymers. Comparing the disiloxane copolymers to their model compounds, we can prove that disiloxane copolymers exhibit extended conjugation. All copolymers and their model compounds were synthesized through Heck reactions, where Bis(tri-tert-butylphosphoranyl) palladium was used as the catalyst. To analyze semiconducting properties of the copolymers, photon absorption and emission and quantum efficiency (integrating sphere) were used, which can reflect a molecule’s molecular orbital information. All copolymers and their model compounds were characterized using TGA, FTIR, NMR, MALDI-TOF, and the GPC machine to show their structural and thermal properties. Our results show we can find conjugation in excited states of disiloxane copolymers with a 20-140 nm red shift compared to the model compounds. The results suggest that we can use disiloxane copolymers in industry, where this research could be applied to a lower cost solution for semiconductors. It is a stable new conjugated polymer and could be used for Organic Light-Emitting Diodes (OLEDs). These copolymers could also be used for organic photovoltaics and sensors. Next steps include finding differences in conjugative properties between trans and cis disiloxane copolymers. Keywords: disiloxane, extended conjugation, semiconductor, copolymer
