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  • Characterization of nanoscale morphology and mechanical properties of conjugated polymer thin films dynamically exposed to a secondary solvent
Title: Characterization of nanoscale morphology and mechanical properties of conjugated polymer thin films dynamically exposed to a secondary solvent
Solution processing techniques are often used to enhance intra and interchain order in semiconducting conjugated polymer thin films used in the active layer of organic optoelectronic devices. We investigate the nanomechanical properties of conjugated polymer thin films arising from solution processing techniques. We find that Young’s Modulus data measured by AM-FM AFM can detect additional changes in film properties not discernible by other commonly used bulk thin-film characterization techniques. For PBDB-T-SF, we detect an increase in molecular order that is not noticable by UV–visible absorption spectroscopy, X-ray diffraction or nanoindentation. PCDTBT, the most amorphous of the polymers studied, shows no changes in absorption or X-ray diffraction data, yet clear changes in Young’s Modulus were detected by AFM. Our study demonstrates the applicability of nanomechanical measurements for characterizing local structural variations in conjugated polymer films. This work is relevant to ongoing efforts to control and understand the complex structure-property-processing relationships of conjugated polymer thin films.  more » « less
Award ID(s):
2117792
PAR ID:
10581492
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Polymer
Volume:
293
Issue:
C
ISSN:
0032-3861
Page Range / eLocation ID:
126625
Subject(s) / Keyword(s):
conjugated polymer thin films
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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