University of Southern Mississipi
Rational design of deformable electronic materials through structure and dynamics study of conjugated polymers
Monday, March 29, 2021
Zoom Webinar Link: https://washington.zoom.us/j/93282716786
Organic semiconducting polymers are promising candidates for stretchable electronics for their mechanical compliance. Donor-Acceptor type conjugated polymers have been the key driver for the recent boost in device performance. Up to date, the effect of the conjugated backbone building block on the thermomechanical property of conjugated polymers has not been carefully studied, despite much work on their influence on the electronic property. In this talk, I will discuss our work on the structure and dynamics study of thin-film thermomechanical property relationship for donor-acceptor polymers with systematically varied donor units on the conjugated polymer ( DPP polymer). We utilized solution small angle neutron scattering to quantify backbone rigidity in solution. To characterize the thermomechanical performance, the pseudo-free standing tensile test was used to obtain the full stress-strain curve. The glass transition temperature was measured for both thin and bulk films using AC-chip calorimetry and DMA, respectively. Thin-film morphology was detected using AFM, UV-vis, and GIWAXS for further understanding. OFET devices were fabricated to test the electronic performance. The backbone structure and thermomechanical property relationship were established and applied to the design of new stretchable conjugated polymers.
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Xiaodan Gu earned his Ph.D. from the Department of Polymer Science and Engineering at the University of Massachusetts Amherst in 2014, focusing on the self-assembly of block copolymers and their lithographic applications. Subsequently, he did a post-doctoral at the Stanford University and SLAC National Accelerator Laboratory, where he studied the morphology of roll-to-roll printed electronics using real-time X-ray scattering at various synchrotron beamlines. He is currently an assistant professor from the School of Polymer Science and Engineering at the University of Southern Mississippi. His current research interests revolve around various fundamental polymer physics phenomena related to conjugated polymers and their derivative devices. His group studies the structure, dynamics, and morphology of conjugated polymers and aims to link their molecular structures to their macroscopic properties through advanced metrology with an emphasis on scattering techniques. He was awarded the NSF Career Award, ACS PMSE Young Investigator, ORAU Powe Junior Faculty Enhancement Award, a contributor to “Young Talents” special issue to Macro Rapid Comm, and “Emerging investigator” special issue for Polymer Chemistry.