Hyperbranched Poly Phenylene Research Articles

Synthesis of Hyperbranched Polyphenylene with High Degree of Polymerization and 100% Degree of Branching from A2 + B3 Suzuki-Miyaura Polycondensation through Intramolecular Catalyst Transfer

Synthesis of Hyperbranched Polyphenylene with High Degree of Polymerization and 100% Degree of Branching from A₂ + B₃ Suzuki-Miyaura Polycondensation through Intramolecular Catalyst Transfer

Hyperbranched Polyphenylene as an Electrode for Li‐Ion Batteries

Polymeric electrodes have attracted considerable attention for their potential as Li‐ion battery (LIB) electrodes due to their tunable structures and sustainable preparation from abundant precursors in an environmentally friendly manner. Herein, hyperbranched polyphenylene (HBP) is synthesized through Suzuki polycondensation and investigated as a potential bipolar electrode for LIBs. The advantages of the hyperbranched architecture in HBP include easy and fast transportation of ions as an electrode. Brunauer–Emmett–Teller (BET) measurement on HBP reveals a high specific surface area and porosity compared with typical linear polymers. The low conductivity in HBP is improved by preparing an HBP/multiwalled carbon nanotube (MWCNT) composite material. The LIB performance for the HBP/MWCNT composite anode electrode shows good cyclic stability and high specific capacity, which are caused by the branching architecture, surface area, and improved electronic conductivity from the MWCNT. This results in easy access and rapid movement of Li ions for improved charge–discharge performance. The ex situ technique using Fourier transform infrared spectroscopy shows a lithium storage mechanism in the HBP electrode. This work shows extensive scope for using the hyperbranched architectural concept to explore and develop high‐performing organic electrodes for future metal‐ion batteries.

A novel functional HPPS/PCL/ZnO composite layer on AZ91 for anticorrosion

AZ91 magnesium alloy was coated with a novel and functional hyperbranched polyphenylene sulfide/poly(ε-caprolactone)/ZnO composite (HPPS/PCL/ZnO) using dip-coating method in methenyl trichloride containing solution for improved corrosion resistance of the alloy in simulated body fluid (SBF). The surface of the coated sample is with lower porosity and high uniformity. The electrochemical and immersion tests suggested that the corrosion resistance of the sample coated HPPS/PCL/ZnO composite layer coated alloy was higher than that of the PCL coated one. After 20 days׳ immersion in SBF, the HPPS/PCL/ZnO coated composite was still smooth and hardly changed. Therefore, the HPPS/PCL/ZnO composite layer can protect the AZ91 magnesium more efficiently.

Synthesis of soluble conjugated polymeric nanoparticles through heterogeneous Suzuki coupling reaction

Conjugated hyperbranched polyphenylene nanoparticles are fabricated by cross coupling reactions between an A2 type monomer 1,4-phenylenediboronic acid (1) and B3 type monomers 1,3,5-triiodobenzene (2) and 1,3,5-tribromobenzene (3). The Suzuki-type polycondensation was conducted with a highly efficient heterogeneous catalyst to give conjugated polymeric nanoparticles which are soluble in a variety of organic solvents. The growth of the hyperbranched polyphenylenes are controlled and eventually terminated by the decomposition of the boronate terminal groups in basic aqueous media in the heterogeneous catalysis system. This method represents a new approach to produce soluble conjugated polymeric nanoparticles with simple and symmetrical monomers with more than two end groups (Ax + By, x ≥ 2, y > 2).

Low-polydispersity Hyperbranched Polyphenylene Sulfide as a Protectant for Palladium Nanocomposites

Abstract A low-polydispersity (Mw/Mn = 1.009) hyperbranched poly(phenylene sulfide) (HPPS) is successfully synthesized by modified polycondensation of an AB2 monomer with a core molecule, and served as the skeleton for synthesis and stabilization of Pd nanoparticle. The effect of different PdCl2:HPPS mass ratios on the formation and stabilization of Pd nanoparticles is discussed. The resulting Pd nanoparticles with small average particle size (2.0 nm) have a narrow distribution (σ = 0.4 nm) and exhibit outstanding thermostability. These results clearly demonstrate HPPS (with uniform molecular weight) as a promising stabilizer for the synthesis of Pd nanoparticles.

Thermal and Photochemical Crosslinking of Hyperbranched Polyphenylene With Organic Azides

Here, we report on the first example of crosslinking (CL) hyperbranched polyphenylene (hb-PPh) with a small molecule crosslinker 1,3,5-tris(azidomethyl)benzene (TAMB). It was successfully shown that CL of the hb-PPh/TAMB (9:1) film is possible either thermally or photochemically making use of fundamentally different reaction mechanisms. Starting from a model reaction to prove the feasibility of the thermal CL reaction, we went on to check both the thermal and the photochemical crosslinkability of micrometer thick films. IR spectroscopy was furthermore used to confirm the CL process. Finally, the thin film morphology of the films before and after CL was investigated by AFM, revealing that the surface morphology was unaffected by the CL processes.

Exploration of Effective Catalysts for Diyne Polycyclotrimerization, Synthesis of an Ester-Functionalized Hyperbranched Polyphenylene, and Demonstration of Its Utility as a Molecular Container with Implication for Controlled Drug Delivery

We present the first examples of a group of effective ruthenium catalysts for polycyclotrimerization. The polymerization reactions of an arylene bipropiolate monomer initiated by the Ru(II−IV) complexes of CpRu(PPh3)2Cl, Cp*Ru(PPh3)2Cl, [Cp*RuCl2]n, and [Ru(η3:η3-C10H16)(μ-Cl)Cl]2 (Cp = cyclopentadienyl, Cp* = pentamethyl-Cp, and C10H16 = 2,7-dimethylocta-2,6-diene-1,8-diyl) produce ester-functionalized poly(aroxycarbonylphenylene) (PACP) with high molecular weights (Mw up to 200 × 103) in good yields (up to 90%). Topological structure of the polymer product can be hyperbranched or cross-linked, tunable by the extent of triple-bond conversion. The degree of branching (DB) of the PACP is ∼0.76, much higher than those of the “conventional” hyperbranched polymers (DB ∼ 0.5). The PACP exhibits high transparency in the visible spectral region. It works as a molecular container, effectively trapping small molecules in its cavities with the aid of hydrogen-bond interaction. The polymer undergoes a bursting hydro...

Characterisation of Thin Composite Films from Hyperbranched Polyphenylene and Thermolabile Hyperbranched Polycarbonate

AbstractThin composite films made from a thermally stable hyperbranched polyphenylene and a thermolabile hyperbranched polycarbonate were prepared on silicon wafers and characterised. The end groups of the polycarbonate were varied in order to accomplish an optimised interaction between the two components and thus the formation of homogeneous blends. The composite films were annealed at 200 °C in order to decompose the hyperbranched polycarbonate which can act as a porogen. The composition of the films before and after the annealing process was investigated applying IR spectroscopy and spectroscopic ellipsometry. Analysis of the data allowed calculating the volume fractions of the two materials within the films.magnified image

NMR Study of Hyperbranched Polyphenylenes from the AB2, (AB2 + AB) and (A2 + B3) Methods

AbstractSummary: The 1H NMR and 13C NMR spectra of hyperbranched polyphenylenes synthesised from AB2, (AB2 + AB) and (A2 + B3) monomers (A: ethynyl group; B: cyclopentadienonyl group) were analysed with respect to the characteristic substructures of these polymers. The broad and overlapping NMR spectra were studied by a combination of 1D and 2D NMR techniques. Furthermore, appropriate model compounds were synthesised, and their 1H and 13C NMR spectra were fully assigned. The signal assignments achieved allow to substantiate the different hyperbranched polyphenylene structures. Steric hindrance in densely packed di‐ and trihexaarylphenyl substituted units of the (A2 + B3) polyphenylenes results in the decrease of the rotation frequency of phenyl rings in these structures to such an extent that the motion is slow on the 1H NMR time scale. This can be proved both by EXSY and variable‐temperature experiments. Steric constraints were also deduced for the AB2 polyphenylenes from signal line shape.Selected spectra from a VT 1H NMR experiment on polymer 7b (solvent: C2D2Cl4; *–13C satellites of the solvent; signal at 7.3 ppm due to traces of CHCl3).magnified imageSelected spectra from a VT 1H NMR experiment on polymer 7b (solvent: C2D2Cl4; *–13C satellites of the solvent; signal at 7.3 ppm due to traces of CHCl3).

Synthesis, characterization and Cis–Trans photoisomerization of a series of hyperbranched conjugated polymers

AbstractA series of hyperbranched polyphenylene vinylenes (HPVs) with different alkoxy substituted end groups were synthesized and characterized. The photoluminescence properties were investigated, and the cis–trans isomerization was found by prolonging the exposure time to UV light for the HPVs. The viscosity and end‐group effects on the photoisomerization were studied. Copyright © 2003 John Wiley & Sons, Ltd.

Role of End Groups on the Glass Transition of Hyperbranched Polyphenylene and Triphenylbenzene Derivatives

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTRole of End Groups on the Glass Transition of Hyperbranched Polyphenylene and Triphenylbenzene DerivativesYoung H. Kim and Richard BeckerbauerCite this: Macromolecules 1994, 27, 7, 1968–1971Publication Date (Print):March 1, 1994Publication History Published online1 May 2002Published inissue 1 March 1994https://doi.org/10.1021/ma00085a048RIGHTS & PERMISSIONSArticle Views899Altmetric-Citations129LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (472 KB) Get e-Alerts Get e-Alerts