Super-Soft Solvent-Free Bottlebrush Elastomers for Touch Sensing

TitleSuper-Soft Solvent-Free Bottlebrush Elastomers for Touch Sensing
Publication TypeJournal Article
Year of Publication2020
AuthorsReynolds, Veronica G., Sanjoy Mukherjee, Renxuan Xie, Adam E. Levi, Amalie Atassi, Takumi Uchiyama, Hengbin Wang, Michael L. Chabinyc, and Christopher M. Bates
JournalMaterials Horizons

The sensitivity of capacitive pressure sensors is primarily determined by the modulus of a soft dielectric layer that reversibly deforms to produce an electrical signal. Unfortunately, the mechanical properties of conventional linear networks are constrained such that a lower limit on softness translates to poor capacitive pressure sensor performance. Here, we overcome this paradigm by leveraging the intrinsic “super-soft” characteristic of bottlebrush polymers. A simple light-induced crosslinking strategy is introduced to facilitate device fabrication and parallel plate capacitive pressure sensors constructed with these bottlebrush polymer networks exhibit up to a 53× increase in sensitivity compared to traditional material formulations, e.g., Sylgard 184. This combination of contemporary synthetic chemistry and application-driven materials design accentuates the opportunities available at the intersection of science and engineering.