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Title: Further Proof of Unconventional Conjugation via Disiloxane Bonds: Double Decker Sesquioxane [vinylMeSi(O 0.5 ) 2 (PhSiO 1.5 ) 8 (O 0.5 ) 2 SiMevinyl] Derived Alternating Terpolymers Give Excited-State Conjugation Averaging That of the Corresponding Copolymers
Here, we report the synthesis of DD SQ terpolymers with alternating biphenyl/terphenyl/stilbene and thiophene/hexylthiophene/bithiophene/thieno- thiophene linkers. These terpolymers were characterized using 1H and 13C nuclear magnetic resonance, gel permeation chromatography, matrix-assisted laser desorption/time-of-flight spectrometry, thermogravimetric analysis, and Fourier- transform infrared with the goal of combining long-wavelength emissions with high quantum yields. Density functional theory modeling studies using the Vienna ab initio simulation package and Gaussian 16 methods were also explored in attempts to determine HOMO-LUMO electronic configurations. Terpolymers’ UV−vis properties demonstrate an emission intermediate between the respective copolymers rather than emission from both units as would be expected from physical mixtures, supporting electronic communication along polymer chains and through cages linked via disiloxane units as seen in previous reports on copolymers of the same systems. In addition, terpolymers of DD, thiophene, and terphenyl/ stilbene offer ΦF that improved from 0.09 for DD/thiophene to 0.20 and 0.24, respectively. Compared to the corresponding terphenyl and stilbene copolymers, terpolymers display 35 nm red-shifted emissions, suggesting that it is possible to combine features of both copolymers in a single terpolymer, suggesting new opportunities to tailor photophysical properties by modifying structures, especially in systems with disiloxane linkers.  more » « less
Award ID(s):
2103602
PAR ID:
10525819
Author(s) / Creator(s):
; ; ; ; ; ;
Editor(s):
Hillmyer, M
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
Macromolecules
Edition / Version:
1
Volume:
55
Issue:
18
ISSN:
0024-9297
Page Range / eLocation ID:
8106 to 8116
Subject(s) / Keyword(s):
terpolymers, conjugation, silsesquioxanes, double decker, photophyics
Format(s):
Medium: X Size: 3.4 Other: cxv
Size(s):
3.4
Sponsoring Org:
National Science Foundation
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