Conjugated polyimides (PI) are successfully synthesized by chemical imidization through in situ silylation of diamines by the alteration of different donor-acceptor monomers. A detailed photophysical characterization is performed in the monomers and different polymers in tetrahydrofuran solutions. The emission spectra of the related donor-acceptor polymers with electron withdrawing cyano groups showed broader and more intense fluorescence bands in comparison to the polymer without -CN groups. The new emission band results from the contribution of two different charge-transfer (CT) pathways: (i) An intramolecular CT (ICT) state in the donor monomers due to the presence of strong electron withdrawing CN groups, and (ii) a intramolecular CT complex (CTC) in the PI polymer between the donor-acceptor monomers, which is red-shifted and shows longer lifetime respect to the ICT of the diamine monomers. The very wide emission band is a very interesting feature for obtaining white light from UV light.
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http://dx.doi.org/10.1021/acs.jpcb.5b00845 | DOI Listing |
J Colloid Interface Sci
January 2025
College of Materials, Fujian Provincial Key Laboratory of Fire Retardant Materials, Xiamen Key Laboratory of Fire Retardant Materials, Xiamen University, Xiamen 361005, China. Electronic address:
Electrochromic (EC) materials based on ion insertion/desertion mechanisms provide a possibility for energy storage. Solution-processable energy storage EC polyamides have great potential for use in smart displays and EC supercapacitors. A suitable monomer structure design is particularly important for enhancing the electrochemical properties of polyamides.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
School of Chemistry & Chemical Engineering, Henan University of Science and Technology, Luoyang, Henan 471023, People's Republic of China.
The sensitive and selective identification of nitroaromatic explosives and industrially ubiquitous nitrates, which are harmful to the environment, is crucial from the viewpoints of security and environmental remediation. New multifunctional fluorescent porous materials that can sense nitro-explosives and nitrates are under continuous development. To this end, this study synthesizes 3,10,15-/-3,10,16-tribromotrinaphtho[3.
View Article and Find Full Text PDFMacromol Rapid Commun
January 2025
Polymer Science, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 3, Groningen, 9747 AG, The Netherlands.
Conjugated polyelectrolytes (CPEs), materials that are defined by a -conjugated backbone and charged ionic functional groups, are frequently prepared through direct polymerization of charged monomer species in aqueous media. This route is, however, often accompanied by labor-intensive work-up procedures, low yields, and ultimately results in materials that are difficult to characterize. To overcome these inconveniences, in this work protection chemistry is applied on sulfonate-functionalized fluorene monomers that are polymerized under standard Suzuki polycondensation conditions to obtain protected donor-acceptor copolymers.
View Article and Find Full Text PDFChemistry
December 2024
Department of Chemistry, University of Ioannina, Ioannina, 45110, Greece.
Covalent organic frameworks (COFs) are considered advanced class materials due to their exotic structural and optical properties. The abundance of starting monomers with variable linkage motifs may give rise to multiple conformations in either 2D or 3D fashion. Tailoring of the abovementioned properties has facilitated the application of COFs in a wide range of applications, which are strongly correlated with energy conversion schemes.
View Article and Find Full Text PDFChemistry
December 2024
Hiroshima University, Chemistry, 1-3-1 Kagamiyama, 739-8526, Higashi-Hiroshima, JAPAN.
The intermolecular host-guest complexation of head-to-tail monomers consisting of cleft-shaped bisporphyrin and trinitrofluorenone units connected by a chiral binaphthyl linker was employed to construct helically twisted supramolecular polymers. Results from 1H NMR, diffusion-ordered NMR spectroscopy, and viscometry experiments revealed that the supramolecular polymerization of these monomers follows a ring-chain competition mechanism. The introduction of bulky substituents at the linker significantly suppressed the formation of macrocyclic oligomers, whereas smaller alkyl chains facilitated the formation of the cyclic form.
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