98%
921
2 minutes
20
In this paper, a new aromatic diamine monomer 4,4'-(2,6-naphthalenediyl)bis[benzenamine]) (NADA) was synthesized and a series of modified PI films containing naphthalene ring structure obtained by controlling the molar ratio of NADA monomer, ternary polymerization with 4,4'-oxydianiline (ODA), and pyromellitic dianhydride (PMDA). The effects of the introduction of the naphthalene ring on the free volume and various properties of PI were investigated by molecular dynamic simulations. The results show that the comprehensive properties of the modified films are all improved to some extent, with 5% thermal weight loss temperature (T) of 569 °C, glass transition temperature (Tg) of 381 °C, tensile strength of 96.41 MPa, and modulus of elasticity of 2.45 GPa. Dielectric property test results show that the dielectric constant (Dk) of the film at 1 MHz is reduced from 3.21 to 2.82 and dielectric loss (Df) reduced from 0.0091 to 0.0065. It is noteworthy that the PI-1 dielectric constant is reduced from 3.26 to 3.01 at 10 GHz with only 5% NADA doping, which is expected to yield the best ratio and provide the possibility of industrial production.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9699469 | PMC |
http://dx.doi.org/10.3390/ma15228014 | DOI Listing |
Chem Sci
August 2025
College of Chemistry and Chemical Engineering, Jiangxi Province Engineering Research Center of Ecological Chemical Industry, Jiujiang University Jiujiang 332005 China
BN-fused aromatic compounds have garnered significant attention due to their unique electronic structures and exceptional photophysical properties, positioning them as highly promising candidates for applications in organic optoelectronics. However, the regioselective synthesis of BN isomers remains a formidable challenge, primarily stemming from the difficulty in precisely controlling reaction sites, limiting structural diversity and property tunability. Herein, we propose a regioselective synthetic strategy that employs 2,1-BN-naphthalene derivatives, wherein selective activation of N-H and C-H bonds is achieved in conjunction with -halogenated phenylboronic acids.
View Article and Find Full Text PDFRSC Med Chem
August 2025
Chinese Medicine Research and Development Center, China Medical University Hospital Taichung 404332 Taiwan
Natural products are an important source for developing anti-cancer agents. Previously, we identified the anti-cancer flavonoid protoapigenone from (Gaud.) and synthesized its derivative, WYC-0209, with improved anti-cancer properties.
View Article and Find Full Text PDFChemistry
September 2025
Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, 560012, India.
Rigid and conformationally restricted dichalcogenides based on 1,8-naphthyl system have attracted significant interest as electron donors in charge transfer complexes and organic electrode materials. Recently, naphthalene-1,8-peri-diselenides have been shown to mimic the function of two major selenoenzymes - iodothyronine deiodinase (Dio) and glutathione peroxidase (GPx) - mainly through two-electron redox processes involving deiodination of thyroid hormones and thiol-mediated reduction of hydrogen peroxide, respectively. Herein, we report that naphthalene-1,8-peri-dichalcogenides can mediate a six-electron reduction of organic nitro compounds to produce the corresponding primary amines at physiologically relevant temperature (37 °C) using water as the solvent.
View Article and Find Full Text PDFActa Crystallogr C Struct Chem
September 2025
August Chełkowski Institute of Physics, University of Silesia,75 Pułku Piechoty Street 1, 41-500 Chorzów, Poland.
The crystal structures of eight compounds whose common features are an aromatic ring (naphthalene or benzene) and the presence of two hydroxymethyl groups or two sulfanylmethyl groups were examined. These are the isomers 1,2-, 1,3-, 1,5- and 1,7-bis(hydroxymethyl)naphthalene, CHO; 2,3-bis(hydroxymethyl)naphthalene, CHO; 2,3-bis(sulfanylmethyl)naphthalene, CHS; 1,2-bis(hydroxymethyl)benzene, CHO; and 1,2-bis(sulfanylmethyl)benzene, CHS. Different positions of the functional groups relative to each other are of fundamental importance in the way the molecules of these compounds are packed in the unit cells and have an impact on the interactions of the molecules of the compounds with each other.
View Article and Find Full Text PDFMacromol Rapid Commun
August 2025
Institute of Organic Chemistry and Macromolecular Chemistry, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.
Three new norbornene monomers carrying naphthyl-based sidechains with varying levels of electron deficiency are synthesized, characterized by H NMR, 2D-NMR, UV-vis, and fluorescence spectroscopies, as well as mass spectrometry. The kinetics of their ring-opening polymerization using a third-generation Grubbs catalyst are established, and the resulting polymers are characterized by size-exclusion chromatography, along with UV-vis and fluorescence spectroscopies. These naphthalene-based polynorbornenes are shown to exhibit fluorescence, accompanied by a quenching behavior when exposed to an electron-rich aromatic compound.
View Article and Find Full Text PDF