Aromatic Polyimides Containing Main-Chain Diphenylaminofluorene–Benzothiazole Motif: Fluorescence Quenching, Two-Photon Properties, and Exciplex Formation in a Solid State

2011 ◽  
Vol 44 (18) ◽  
pp. 7194-7206 ◽  
Author(s):  
Matthew J. Dalton ◽  
Ramamurthi Kannan ◽  
Joy E. Haley ◽  
Guang S. He ◽  
Daniel G. McLean ◽  
...  
Keyword(s):  
Solid State ◽  
Fluorescence Quenching ◽  
Main Chain ◽  
Aromatic Polyimides ◽  
Two Photon ◽  
Exciplex Formation

scholarly journals Two-photon interference of weak coherent laser pulses recalled from separate solid-state quantum memories

2013 ◽  
Vol 4 (1) ◽  
Author(s):  
Jeongwan Jin ◽  
Joshua A. Slater ◽  
Erhan Saglamyurek ◽  
Neil Sinclair ◽  
Mathew George ◽  
...  
Keyword(s):  
Solid State ◽  
Laser Pulses ◽  
Two Photon

Thermosetting Mechanism Study of Organosilicon Polymer Containing Carborane by Solid-State NMR Spectroscopy

1999 ◽  
Vol 576 ◽  
Author(s):  
H. Kimura ◽  
K. Okita ◽  
M. Ichitani ◽  
M. Yonezawa ◽  
T. Sugimoto
Keyword(s):  
Solid State ◽  
Solid State Nmr ◽  
Nmr Spectra ◽  
Main Chain ◽  
Addition Reaction ◽  
Side Chain ◽  
Mechanism Study ◽  
Nmr Method ◽  
Organosilicon Polymer ◽  
Thermal Stable

ABSTRACTThe thermosetting mechanism of an organosilicon polymer containing carborane has been studied utilizing the 13and 29Si solid-state NMR method. The polymer having C≡C bonds in the main chain and CH═CH2, Si-H bonds, and carborane in the bulky side chain, shows a very highly thermal stability in air by curing. From 13C and 29Si NMR spectra of the polymer, it was found that the intermolecular cross-linking reactions of the polymer was due to (1) the diene reaction between Ph-C≡C and C≡C and (2) the addition reaction between side chain terminal and Ph-C≡C and between CH═CH2 and Si–H, and a very highly thermal stable structure is formed.

Solid State Carbon-13 NMR Studies of Vulcanized Elastomers. II, Sulfur Vulcanization of Natural Rubber

1987 ◽  
Vol 60 (2) ◽  
pp. 252-277 ◽  
Author(s):  
A. M. Zaper ◽  
J. L. Koenig
Keyword(s):  
Solid State ◽  
Nmr Spectra ◽  
Molecular Motion ◽  
Main Chain ◽  
Repeat Unit ◽  
Crosslinking Agent ◽  
Nmr Studies ◽  
Structural Modifications ◽  
Chain Isomerization ◽  
Cyclic Sulfide

Abstract In summary, the solid-state C-13 NMR technique has proven to be a significant method for the detection of crosslinks and other structural modifications in sulfur-vulcanized NR systems. The use of sulfur as a crosslinking agent by itself generates a considerable amount of main-chain structural modifications. Cyclic sulfide structures and cis-to-trans chain isomerization are detected in addition to polysulfidic crosslinks which are found attached to different carbons of the NR repeat unit. The phenomenon of reversion has also been detected in this study. The nature of the spectral broadening in the NMR spectra of the highly cured vulcanizates has two origins. The broadening arises from lack of molecular motion in the system and from an increase in chemical shift dispersion due to the new structures formed with crosslinking.

scholarly journals Nonlinear Optical Pigments. Two-Photon Absorption in Crosslinked Conjugated Polymers and Prospects for Remote Nonlinear Optical Thermometry

Polymers ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 1670
Author(s):  
Jan K. Zaręba ◽  
Marcin Nyk ◽  
Marek Samoć
Keyword(s):  
Solid State ◽  
Conjugated Polymers ◽  
Nonlinear Optical ◽  
Photon Absorption ◽  
Model Compounds ◽  
Two Photon Absorption ◽  
Two Photon ◽  
Sensing Applications ◽  
Spectrally Resolved ◽  
The Impact

Nonlinear optical (NLO) pigments are compounds insoluble in solvents that exhibit phenomena related to nonlinear optical susceptibilities (χ(n) where n = 2,3,...), e.g., two-photon absorption (2PA) which is related to the imaginary part of χ(3). Determination of spectrally-resolved 2PA properties for NLO pigments of macromolecular nature, such as coordination polymers or crosslinked polymers, has long been a challenging issue due to their particulate form, precluding characterizations with standard techniques such as Z-scan. In this contribution, we investigate thus far unknown spectrally-resolved 2PA properties of a new subclass of NLO pigments—crosslinked conjugated polymers. The studied compounds are built up from electron-donating (triphenylamine) and electron-withdrawing (2,2’-bipyridine) structural fragments joined by vinylene (Pol1) or vinyl(4-ethynylphenyl) (Pol2) aromatic bridges. 2PA properties of these polymers have been characterized in broad spectral range by specially modified two-photon excited fluorescence (TPEF) techniques: solid state TPEF (SSTPEF) and internal standard TPEF (ISTPEF). The impact of self-aggregation of aromatic backbones on the 2PA properties of the polymers has been evaluated through extended comparisons of NLO parameters, i.e., 2PA cross sections (σ2) and molar-mass normalized 2PA merit factors (σ2/M) with those of small-molecular model compounds: Mod1 and Mod2. By doing this, we found that the 2PA response of Pol1 and Pol2 is improved 2–3 times versus respective model compounds in the solid state form. Further comparisons with 2PA results collected for diluted solutions of Mod1 and Mod2 supports the notion that self-aggregated structure contributes to the observed enhancement of 2PA response. On the other hand, it is clear that Pol1 and Pol2 suffer from aggregation-caused quenching phenomenon, well reflected in time-resolved fluorescence properties as well as in relatively low values of quantum yield of fluorescence. Accordingly, despite improved intrinsic 2PA response, the effective intensity of two-photon excited emission for Pol1 and Pol2 is slightly lower relative to Mod1 and Mod2. Finally, we explore temperature-resolved luminescence properties under one- (377 nm), two- (820 nm), and three-photon excitation (1020 nm) conditions of postsynthetically Eu3+-functionalized material, Pol1-Eu, and discuss its suitability for temperature sensing applications.

Tryptophan and ATTO 590: Mutual Fluorescence Quenching and Exciplex Formation

2014 ◽  
Vol 118 (29) ◽  
pp. 8471-8477 ◽  
Author(s):  
Ujjal Bhattacharjee ◽  
Christie Beck ◽  
Arthur Winter ◽  
Carson Wells ◽  
Jacob W. Petrich
Keyword(s):  
Fluorescence Quenching ◽  
Exciplex Formation

Exciplex formation in solid state blends of charge-transfer type AFX dyes and bisimide compounds

2012 ◽  
Author(s):  
Matthew J. Dalton ◽  
David J. Stewart ◽  
Ramamurthi Kannan ◽  
Rachel N. Swiger ◽  
Dominic L. Orseno ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Solid State ◽  
Exciplex Formation
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