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  • Triphenylene containing blue-light emitting semi-fluorinated aryl ether polymers with excellent thermal and photostability
Title: Triphenylene containing blue-light emitting semi-fluorinated aryl ether polymers with excellent thermal and photostability
Integration of polycyclic aromatic hydrocarbon (PAH) units into semi-fluorinated polymers affords high thermal stability and excellent processability for potential applications in optoelectronic, gas-separation, and advanced composites. Base-promoted step-growth polycondensation of commercial bisphenols with new triphenylene containing bis-trifluorovinyl ether (TFVE) monomers affords semi-fluorinated arylene vinylene ether (FAVE) polymers in good yields. The solution-processable polymers form tough transparent films and produce substitution dependent blue-light emission in solution with emission quantum yields ranging from 7.2–12% (in dichloromethane). Although predominantly amorphous with high glass transition temperatures ( T g ) ranging from 176–243 °C, powder X-ray diffraction studies show typical molecular diameter and pi-stacking reflections for triphenylene polymers. The polymers exhibited excellent thermal stability, solution photostability, and remarkable thermal oxidative photostability after heating at 250 °C for 24 h in air. Further, a model post-polymerization Scholl coupling afforded a novel semi-fluorinated hexabenzocoronene polymer with new optical properties. Time-dependent density functional theory (TD-DFT) computations were also performed using SMD (dichloromethane)- ω B97XD/BS1 (BS1 = 6-31G(d′) for C, H, O and F). This work demonstrated the synthesis and characterization of processable, blue-light emitting, thermally stable triphenylene enchained semi-fluorinated aryl ether polymers.  more » « less
Award ID(s):
2102552
PAR ID:
10345243
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Materials Chemistry Frontiers
Volume:
6
Issue:
11
ISSN:
2052-1537
Page Range / eLocation ID:
1391 to 1404
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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