POS4-0317
Molecular Design of Side-Chain Liquid Crystalline Azopolymers with Tunable Dielectric Polarization for Highly Sensitive Thermoresponsive Triboelectric Sensors
Topic
S4. Colloids, Interfaces, and Molecular Assemblies for Functional Soft Materials
When and Where
Sep 29, 2026
08:30 - 09:30
Room 301 (Grand Ballroom)
Session Chairs
Hae Jung SON
Boseok KANG
Presenter(s)
Chaeyeon Woo (Hanyang University)
Co-Author(s)
Abstract
Polymer-based triboelectric nanogenerators (TENGs) are promising platforms for self-powered sensing applications; however, their temperature sensitivity is often limited by dipole disorder and thermally induced randomization near the glass transition temperature (Tg), resulting in insufficient dielectric polarization. To address this issue, we developed liquid-crystalline azopolymers (PAZO-n) with tunable molecular structures to achieve temperature-dependent dipole alignment and enhanced interfacial polarization. A series of azobenzene-functionalized side-chain (PAZO-n) with different alkyl spacer lengths (n=3,6, and 12) were synthesized through azo coupling, Williamson etherification, and methacrylation, followed by AIBN-initiated free-radical polymerization. The resulting PAZO films were subsequently spin-coated onto O2-plasma-treated PDMS substrates to fabricate PAZO/PDMS bilayer films. By systematically controlling the spacer length, molecular weight (Mw), film thickness, and annealing temperature near Tg, the molecular packing, dipole mobility, and dielectric polarization of the bilayer films were effectively tailored. Among the bilayer films, the PAZO-6/PDMS film exhibited the optimal balance between dipole mobility and structural stability, leading to the enhanced polarization and triboelectric performance. Consequently, the bilayer film with high Mw of PAZO-6 achieved the highest triboelectric output, delivering the output voltage of 10.05 ± 0.19 V and a maximum power density of 9.95 ± 3.04 μW cm−2. Furthermore, the optimized bilayer film showed a temperature sensitivity of approximately 280% ranging from 30 °C to 80 °C surpassing the sensitivity of previously reported triboelectric sensors. These results demonstrate that the molecular engineering of liquid-crystalline azopolymers, combined with bilayer dielectric design, provides an effective strategy for the development of highly sensitive thermoresponsive TENGs.
