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Synapse-Mimicking Memristors Based on 3,6-Di( tpy)-9-Phenylcarbazole Unimer and Its Copolymer with Cobalt(II) Ions. Polymers (Basel) 2024; 16:542. [PMID: 38399920 PMCID: PMC10892321 DOI: 10.3390/polym16040542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Revised: 02/09/2024] [Accepted: 02/14/2024] [Indexed: 02/25/2024] Open
Abstract
The title compound, unimer U (tpy stands for 2,2':6',2″-terpyridin-4'-yl end-group), by itself shows the memristor effect with a retention time of 18 h and persistence of 11 h. Its coordination copolymer with Co(II) ions, [CoU]n, exhibits multimodal resistance changes similar to the synaptic responses observed in biological systems. More than 320 cycles of potentiation and depression measured in continuous sequence occurred without observing a significant current change, confirming the operational stability and reproducibility of the device based on the [CoU]n polymer. The synaptic effect of a device with an indium tin oxide (ITO)/[CoU]n/top-electrode (TE) configuration is more pronounced for the device with TE = Au compared to devices with TE = Al or Ga. However, the latter TEs provide a cost-effective approach without any significant compromise in device plasticity. The detected changes in the synaptic weight, about 12% for pair-pulse facilitation and 80% for its depression, together with a millisecond trigger and reading pulses that decay exponentially on the time scale typical of neurosynapses, justify the device's ability to learn and memorize. These properties offer potential applications in neuromorphic computation and brain-inspired synaptic devices.
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2
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Pyrazinyl and pyridinyl bis-azomethines formation: an experimental and computational study. Sci Rep 2023; 13:17383. [PMID: 37833405 PMCID: PMC10575867 DOI: 10.1038/s41598-023-44585-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 10/10/2023] [Indexed: 10/15/2023] Open
Abstract
Formation of bis-azomethines from hydrazine and heterocyclic aromatic carbaldehydes, namely pyridine-2-carbaldehyde and pyrazine-2-carbaldehyde, is studied using density functional theory. The theoretical investigation is correlated with experimental results obtained by means of NMR spectroscopy. The presence of bis-hemiaminal intermediates is evidenced by NMR spectra while surprisingly stable hemiaminal intermediate was isolated experimentally. Water, methanol and acetic acid were outlined to play a crucial role as active catalysts of elementary steps of the reaction mechanisms. The possible reaction sequences, i.e. addition-dehydration-addition-dehydration or addition-addition-dehydration-dehydration are investigated and discussed. Also, alternative mechanistic path via ionic mechanism was proposed for the formation of hemiaminals.
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3
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Hemiacetal-based dynamic systems: a new mechanistic insight. Org Biomol Chem 2023; 21:6956-6968. [PMID: 37581612 DOI: 10.1039/d3ob00668a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/16/2023]
Abstract
The formation of hemiacetals from pyrazine trifluoromethylketone as a model receptor and four simple alcohols was studied by using quantum chemical calculations and NMR spectroscopy. Free energy profiles for four types of mechanistic pathways were calculated and discussed with respect to kinetic and thermodynamic measurements. We show that hemiacetal formation is facilitated by an assisted proton transfer process via a pseudo eight-membered transition state which brings the theory and experiment into close agreement. Also, a newly proposed mechanistic pathway for hemiacetal formation via a five-membered transition state leading to zwitterionic intermediates is discussed. Direct proton transfer in a pseudo four-membered transition state can be ruled out due to the high energy of transition states with respect to other mechanistic pathways. We also show that in the case of hemiacetals, water and alcohol molecules cannot account sufficiently for the H-transfer process via six-membered transition states.
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Novel Metallo-Supramolecular Polymers with 1-Thioxophosphole Main-Chain Units and Remarkable Photoinduced Changes in Their Resonance Raman Spectra. Polymers (Basel) 2022; 14:polym14235207. [PMID: 36501602 PMCID: PMC9739564 DOI: 10.3390/polym14235207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 11/17/2022] [Accepted: 11/22/2022] [Indexed: 12/02/2022] Open
Abstract
New low-bandgap unimers, with the central thiophene-(1-thioxophosphole)-thiophene (TPT) ring sequence and 2,2':6',2″-terpyridin-4'-yl (tpy) end groups connected to the central unit via conjugated linkers of different size, are prepared and assembled with Zn(II) and Fe(II) ions to metallo-supramolecular polymers (MSPs) that are studied regarding their properties. The most interesting feature of Zn-MSPs is the luminescence extended deep into the NIR region. Fe-MSPs not only show the metal-to-ligand charge transfer (MLCT) manifested by the MLCT band (an expected feature) but also an as-yet-undescribed remarkable phenomenon: specific damping of the bands of the TPT sequence in the resonance Raman spectra taken from solid Fe-MSPs using the excitation to the MLCT band (532 nm). The damping is highly reversible at the low laser power of 0.1 mW but gradually becomes irreversible as the power reaches ca. 5 mW. The revealed phenomenon is not shown by the same Fe-MSPs in solutions, nor by Fe-MSPs containing no phosphole units. A hypothesis is proposed that explains this phenomenon and its dependence on the irradiation intensity as a result of the interplay of three factors: (i) enhancement of the MLCT process by excitation radiation, (ii) the electron-acceptor character of the 1-thioxophosphole ring, and (iii) morphological changes of the lattice and their dependence on the population of new structures in the lattice.
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Kinetics of the Photoexcited States in Thin Films of Metallo-Supramolecular Polymers With Ditopic Thiophene-Bridged Terpyridine Ligands. Front Chem 2022; 9:766121. [PMID: 35127641 PMCID: PMC8812722 DOI: 10.3389/fchem.2021.766121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Accepted: 12/21/2021] [Indexed: 11/13/2022] Open
Abstract
Managing the excited-state decay by a supramolecular structure is a crucial issue for organic photovoltaics. We show that in thin films of metallo-supramolecular polymers made of bis(terpyridine-4′-yl)terthiophenes and Zn2+ coupling ions, the photoexcited states generated by ultrashort laser pulses at the wavelength of 440 nm decay by the bi-molecular annihilation predominantly controlled by the Förster transfer between singlet states. During this bi-molecular annihilation of singlet states, intermediate hot triplet pairs are formed, which subsequently dissociate into long-living diffusing triplet states. It explains a significant shortening of the triplet state rise time with increasing pump fluence. The diffusion coefficient of triplets showed power-law time dependence, with its exponent proportional to the pump fluence, decreasing thus the diffusivity of triplets.
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Effects of the halogenido ligands on the Kumada-coupling catalytic activity of [Ni{ t BuN(PPh 2) 2-κ 2P}X 2], X = Cl, Br, I, complexes. RSC Adv 2022; 12:2227-2236. [PMID: 35425218 PMCID: PMC8979229 DOI: 10.1039/d1ra04572e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Accepted: 12/24/2021] [Indexed: 11/21/2022] Open
Abstract
Novel nickel(ii) complexes bearing ( t butyl)bis(diphenylphosphanyl)amine and different halogenido ligands, [Ni(P,P)X2] = [Ni{ t BuN(PPh2)2-κ2P}X2], (X = Cl, Br, I) are prepared, characterized by IR and NMR spectroscopy, mass spectrometry and X-ray crystallography, and tested as catalysts in the Kumada cross-coupling reaction of model substituted iodobenzenes and p-tolylmagnesium bromide. The data obtained together with DFT calculations indicate that these new catalysts operate in the Ni(i)-Ni(iii) mode. The highest catalytic activity and selectivity are exhibited by [Ni(P,P)Cl2], which is most easily reduced by the used Grignard reagent to the Ni(i) state. This process is much more energy demanding in the case of the bromido and iodido complexes, causing the appearance of the induction period. [Ni(P,P)Cl2] is also very active in the cross-couplings of substrates with iodine atoms sterically shielded by ortho substituents. The data obtained are in good accordance with the described positive effect of the increased electron-releasing power of N-substituents R' on the overall catalytic performance of [Ni{R'N(PPh2)2-κ2P}X2] complexes.
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7
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Glossary of terms relating to electronic, photonic and magnetic properties of polymers (IUPAC Recommendations 2021). PURE APPL CHEM 2021. [DOI: 10.1515/pac-2020-0501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
These recommendations are specifically for polymers and polymer systems showing a significant response to an electromagnetic field or one of its components (electric field or magnetic field), i.e., for electromagnetic-field-responsive polymer materials. The structures, processes, phenomena and quantities relating to this interdisciplinary field of materials science and technology are herein defined. Definitions are unambiguously explained and harmonized for wide acceptance by the chemistry, physics, polymer and materials science communities. A survey of typical electromagnetic-field-responsive polymers is included.
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8
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Structural and catalytic properties of the [Ni(BIPHEP)X2] complexes, BIPHEP = 2,2-diphenylphosphino-1,1-biphenyl; X = Cl, Br. Inorganica Chim Acta 2021. [DOI: 10.1016/j.ica.2021.120300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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9
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Oleate-modified hyaluronan: Controlling the number and distribution of side chains by varying the reaction conditions. Carbohydr Polym 2021; 267:118197. [PMID: 34119164 DOI: 10.1016/j.carbpol.2021.118197] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 05/11/2021] [Accepted: 05/11/2021] [Indexed: 11/27/2022]
Abstract
In this work, low molecular weight hyaluronan was chemically modified by oleoyl moieties utilising mixed anhydrides methodology. The activation of oleic acid with benzoyl chloride in organic solvents miscible with water was followed by NMR spectroscopy. The product selectivity correlates with the solvent's Hildebrand solubility parameter. Furthermore, the effect of the solvent for the mixed anhydride formation was elucidated by density functional theory (DFT) and showed that the reactions are faster in acetonitrile or alcohols than in hexane. Furthermore, the solvent demonstrated to control the substituent distribution pattern along HA chain during esterification. An even distribution of substituents was observed in reactions performed in water mixed with ethers. The substituent distribution pattern clearly influenced the aggregation behaviour of amphiphilic HA, controlling the stability of the delivery system, while increasing the encapsulation capacity.
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10
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Iron (II) Metallo-Supramolecular Polymers Based on Thieno[3,2- b]thiophene for Electrochromic Applications. Polymers (Basel) 2021; 13:polym13030362. [PMID: 33498749 PMCID: PMC7865520 DOI: 10.3390/polym13030362] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 01/19/2021] [Accepted: 01/20/2021] [Indexed: 01/31/2023] Open
Abstract
Four new bis(tpy) unimers with different linkers between the thieno[3,2-b]thiophene-2,5-diyl central unit and terpyridine-4′-yl (tpy) end-groups: no linker (Tt), ethynediyl (TtE), 1,4-phenylene (TtPh) and 2,2′-bithophene-5,5′-diyl (TtB) are prepared, characterized, and assembled with Fe2+ ions to metallo-supramolecular polymers (Fe-MSPs). The Fe-MSP films prepared by spin-casting on Indium Tin Oxide (ITO) glass are characterized by atomic force microscope (AFM) microscopy, cyclic voltammetry, and UV/vis spectroscopy and studied for their electrochromism and effect of the unimer structure on their electrochromic performance. Of the studied MSPs, Fe-Tt shows the highest optical contrast as well as coloration efficiency (CE = 641 cm2 C−1) and the fastest optical response. This makes it an excellent candidate for possible use in electrochromic devices.
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Controlled Tuning of the Size of Ag-Hydrosol Nanoparticles by Nonstabilized THF and Detection of Peroxides in THF. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:9831-9840. [PMID: 31266307 DOI: 10.1021/acs.langmuir.9b01449] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Surface plasmon extinction (SPE) spectra of plasmonic nanoparticles (NPs) are sensitive indicators of their composition, size, shape, interparticle interactions, and of the dielectric constant of their ambient. In this study, rapid changes in SPE spectra of Ag NPs suggesting variations in NP size and concentration were detected after addition of aged tetrahydrofuran (THF). Using time-dependent UV/vis spectroscopy combined with factor analysis, transmission electron microscopy imaging, selected-area electron diffraction, and energy-dispersive X-ray analysis, we observed that an over-limit amount of aged THF fully dissolved Ag NPs with no plasmon recovery. By contrast, an under-limit amount led to incomplete dissolution of Ag NPs and, after reaching the turnover point, to spontaneous recrystallization on residual Ag nuclei, as demonstrated by the SPE band intensity recovery to the original or even higher values. The newly formed Ag NPs were isometric, and their diameter was dependent on the added amount of THF. Furthermore, both Ag NP dissolution and recrystallization were caused by THF peroxides and their reduction products. Therefore, the dissolution of Ag NPs and the resulting hydrosol bleaching may be used as an indicator of the presence of peroxides in THF. Moreover, the reaction of aged THF with Ag NPs can be employed as a tool for tuning the size of Ag NPs in hydrosols.
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Effect of the configuration of poly(lactic acid) and content of poly(oxyethylene) blocks to the structure and functional properties of poly(lactic acid)‐
block
‐poly(oxirane)‐based nanofibrous electrospun polyester–ether–urethanes used as potential drug‐delivery system. J Biomed Mater Res B Appl Biomater 2019; 107:2378-2387. [DOI: 10.1002/jbm.b.34331] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 12/21/2018] [Accepted: 01/13/2019] [Indexed: 11/07/2022]
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13
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Nomenclature and terminology for dendrimers with regular dendrons and for hyperbranched polymers (IUPAC Recommendations 2017). PURE APPL CHEM 2019. [DOI: 10.1515/pac-2016-1217] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The present document provides recommendations for (i) definitions of terms related to dendrimers with regular dendrons and to hyperbranched polymers, and (ii) nomenclature for naming these complex compounds on the basis of structure-based nomenclature for regular and irregular organic polymers, including adjustments required for specifying dendritic and hyperbranched macromolecular structures. The recommendations and the examples deal with organic-chemical structures only. Nevertheless, the general principles described in this document can similarly be applied to inorganic and to hybrid inorganic-organic dendrimers and hyperbranched macromolecules.
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Attachment of a 1,8‐Naphthalimide Moiety to a Conjugated Polythiophene Efficiently Improves the Sensing Abilities of Naphthalimide‐Based Materials. MACROMOL CHEM PHYS 2018. [DOI: 10.1002/macp.201800436] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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15
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Combination of phosphonium and ammonium pendant groups in cationic conjugated polyelectrolytes based on regioregular poly(3-hexylthiophene) polymer chains. Eur Polym J 2018. [DOI: 10.1016/j.eurpolymj.2018.01.029] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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16
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Assembling of bis(tpy)fluorenes with Zn2+ and Fe2+ ions into metallo-supramolecular polymers with highly efficient white-light emission. POLYMER 2017. [DOI: 10.1016/j.polymer.2017.06.037] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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17
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Structure-stability correlation of copolyimide membranes derived from aliphatic/alicyclic/aromatic diamine and aromatic dianhydrides. J Appl Polym Sci 2017. [DOI: 10.1002/app.45227] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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18
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Arrays of Ag and Au Nanoparticles with Terpyridine- and Thiophene-Based Ligands: Morphology and Optical Responses. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:4146-4156. [PMID: 28422502 DOI: 10.1021/acs.langmuir.7b00126] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The assembly of Ag and Au nanoparticles (NPs) into nanoparticulate arrays mediated by terpyridine (tpy), 4'-(2-thienyl)terpyridine (T-tpy), and short α,ω-bis(tpy)oligothiophene ligands has been accomplished at the interface between the Ag or Au NP hydrosol and a solution of the molecular species in dichloromethane. The relationship between the morphology and the optical responses of the arrays has been investigated by advanced methods of TEM (transmission electron microscopy) image analysis and surface plasmon extinction (SPE) spectra. It has been established that the size of islands of closely spaced NPs rather than the average interparticle distance affects the extent of delocalization of the surface plasmon excitations and thus also the SPE spectra. Furthermore, the structure of surface-adsorbate complexes formed in these arrays has been investigated by SERS spectral measurements carried out as a function of the excitation wavelength. Photoinduced charge transfer (CT) transitions from the neutral Ags0 and Aus0 adsorption sites on metal NPs to antibonding orbitals of the adsorbates have been identified for Ag/tpy, Ag/T-tpy, Au/tpy, and Au/T-tpy nanoparticulate arrays. Although the surface-adsorbate complexes displaying a photoinduced CT are known for Ag NPs, the Aus0 surface complexes with this CT are newly reported. Bis(tpy)oligothiophenes were found to be attached to both Ag and Au NPs via the tpy group(s). The match between the interparticle distances within the NP islands and the lengths of the oligomers molecules indicates that the molecules act as interparticle linkers. In this case, unequivocal spectral marker band evidence of the Ags0 as well as Aus0 surface complex formation has not been obtained.
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20
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Synthesis and characterization of metallo-supramolecular polymers from thiophene-based unimers bearing pybox ligands. RSC Adv 2017. [DOI: 10.1039/c6ra26665g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
A series of novel metallo-supramolecular polymers was prepared, based on 2,6-bis(2-oxazolinyl)pyridine chelating groups bridged with thiophene, bithiophene and thienothiophene as a linker, beginning from commercially available (chelidamic) acid.
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Alcohol- and water-soluble bis(tpy)quaterthiophenes with phosphonium side groups: new conjugated units for metallo-supramolecular polymers. Dalton Trans 2016; 45:1208-24. [PMID: 26667325 DOI: 10.1039/c5dt04133c] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Bis(tpy)quaterthiophenes with symmetrically distributed two and four 6-bromohexyl side groups were prepared and modified by the reaction with triethylphosphine to give the corresponding ionic species. Both ionic and non-ionic bis(tpy)quaterthiophenes (unimers) were assembled with Zn(2+) and Fe(2+) ions to conjugated metallo-supramolecular polymers (MSPs), of which the ionic ones are soluble in alcohols and those derived from tetrasubstituted unimers are soluble even in water. The differences in assembly are specified between systems with (i) ionic and non-ionic unimers, (ii) Zn(2+) and Fe(2+) ion couplers, and (iii) methanol and water solvents. A substantial decrease in the stability of Fe-MSPs and a surprisingly high red shift of the luminescence band of Zn-MSPs were observed on going from methanol to aqueous solutions.
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Morphology and Kinetics of Aggregation of Silver Nanoparticles Induced with Regioregular Cationic Polythiophene. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:2-11. [PMID: 26630552 DOI: 10.1021/acs.langmuir.5b03365] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The aggregation kinetics of negatively charged borate-stabilized silver nanoparticles (NPs) induced by the cationic regioregular polythiophene polyelectrolyte poly{3-[6-(1-methylimidazolium-3-yl)hexyl]thiophene-2,5-diyl bromide} (PMHT-Br) and the morphology of formed aggregates have been investigated via ultraviolet-visible light (UV-vis) spectroscopy, transmission electron microscopy (TEM), zeta (ζ) potential measurements, dynamic light scattering (DLS), and time-resolved small-angle X-ray scattering (SAXS). Two or three populations of NPs are formed within milliseconds upon mixing the components, which differ in the mean size, extent of polymer coating, and time stability. These characteristics are primarily controlled by the PMHT-Br to Ag-NPs ratio. Population of single NPs of a mean size of ∼5 nm is present in every system and is mostly stable for a long time. At low ratios, the single NPs are most probably almost free of polymer chains and the second population includes slow, but in a limited extent, growing NPs in which single NPs might be interconnected by polymer chains. At the ratios corresponding to the charge balance in the system (ca. zero ζ-potential of NPs), the NPs aggregate, forming a second population that continuously grows in size, and finally undergo sedimentation. At the high ratios, three long-time stable populations of NPs are observed, having mean sizes of ca. 5, 13, and 35 nm; all NPs should be fully coated with PMHT-Br, giving them a positively charged stabilizing shell.
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Self-doping of polyaniline prepared with the FeCl3/H2O2system and the origin of the Raman band of emeraldine salt at around 1375 cm−1. POLYM INT 2015. [DOI: 10.1002/pi.4983] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Time-Resolved Transient Optical Absorption Study of Bis(terpyridyl)oligothiophenes and Their Metallo-Supramolecular Polymers with Zn(II) Ion Couplers. J Phys Chem A 2015; 119:6203-14. [DOI: 10.1021/jp512213s] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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A Kumada Coupling Catalyst, [Ni{(Ph
2
P)
2
N(CH
2
)
3
Si(OCH
3
)
3
‐
P,P′
}Cl
2
], Bearing a Ligand for Direct Immobilization Onto Siliceous Mesoporous Molecular Sieves. Eur J Inorg Chem 2015. [DOI: 10.1002/ejic.201500447] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Erratum to: Nomenclature and graphic representations for chemically modified polymers (IUPAC Recommendations 2014). PURE APPL CHEM 2015. [DOI: 10.1515/pac-2015-5002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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29
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Nomenclature and graphic representations for chemically modified polymers (IUPAC Recommendations 2014). PURE APPL CHEM 2015. [DOI: 10.1515/pac-2014-0610] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractA new source-based nomenclature system is described which indicates that a particular polymer has been chemically modified. A connective within the name of a polymer, -mod-, is introduced for this purpose as in poly[(A)-mod-(B)]. The system is intended to be used in accordance with source-based naming of polymers but also provides for the use of structure-based names when it is unavoidable. It embraces: (1) modification of a constitutional unit into another, the unique structure of which is known; and (2) a more general modification of a constitutional unit resulting in any one of a number of possible structures. In addition, a new symbol, ∼>, is proposed for use in graphic representations of the structure of modified polymers.
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Definitions of terms relating to individual macromolecules, macromolecular assemblies, polymer solutions, and amorphous bulk polymers (IUPAC Recommendations 2014). PURE APPL CHEM 2015. [DOI: 10.1515/pac-2013-0201] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
AbstractThis document defines terms relating to the properties of individual macromolecules, macromolecular assemblies, polymer solutions, and amorphous bulk polymers. In the section on polymer solutions and amorphous bulk polymers, general and thermodynamic terms, dilute solutions, phase behaviour, transport properties, scattering methods, and separation methods are considered. The recommendations are a revision and expansion of the IUPAC terminology published in 1989 dealing with individual macromolecules, macromolecular assemblies, and dilute polymer solutions. New terms covering the principal theoretical and experimental developments that have occurred over the intervening years have been introduced. Polyelectrolytes are not included.
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Alcohol-soluble bis(tpy)thiophenes: new building units for constitutional dynamic conjugated polyelectrolytes. Phys Chem Chem Phys 2015; 17:13743-56. [PMID: 25941777 DOI: 10.1039/c5cp01000d] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Constitutional dynamics and spectral properties of conjugated ionic unimers and their metallo-supramolecular dynamers with Zn(ii) and Fe(ii) ion couplers are presented together with new knowledge on the MLCT band of bis(tpy)Fe(ii) units.
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Stability of MEH-PPV: Poly{[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene]vinylene} in solutions exposed to air in the dark and at daylight at laboratory temperature. Polym Degrad Stab 2014. [DOI: 10.1016/j.polymdegradstab.2014.08.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Transport properties and ion binding in aqueous solutions of alkali metal salts of poly(thiophen-3-ylacetic acid). J Mol Liq 2014. [DOI: 10.1016/j.molliq.2014.04.042] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Abbreviations of polymer names and guidelines for abbreviating polymer names (IUPAC Recommendations 2014). PURE APPL CHEM 2014. [DOI: 10.1515/pac-2012-1203] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractThis document provides some basic rules and guidelines regarding the use and creation of abbreviations for the names of polymers. An extended list of currently used abbreviations for polymers and polymeric materials is appended.
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Effects of the polymerization temperature on the structure, morphology and conductivity of polyaniline prepared with ammonium peroxodisulfate. Eur Polym J 2013. [DOI: 10.1016/j.eurpolymj.2013.08.018] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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UV/Vis Study of the Alkali Salts of Poly(thiophen-3-ylacetic acid) in Water. Acta Chim Slov 2012; 59:571-581. [PMID: 24061313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023] Open
Abstract
UV/Vis spectroscopic investigation of aqueous solutions of regio-irregular poly(thiophen-3-ylacetic acid) (PTAA) with and without methyl-ester groups in the presence of sodium and lithium ions as counterions is presented. The samples were carefully purified and characterized with respect to molar mass and the amount of -COOH groups present. We examined how the UV/Vis spectra of solution change with aging of PTAA solution, polymer concentration, addition of low molecular weight salt, temperature, and some other parameters. We show that results crucially depend on whether the spectra are taken for freshly prepared or mature solutions. We demonstrate the validity of the Beer-Lambert law for PTANa, PTAA/Na, and PTAA/Li (aged solution), and violation of this law for PTANa/Me (fresh) solutions in water; the latter system is instead found to exhibit an isosbetic point at 402 nm. We prove that UV/Vis spectra of polythiophene derivatives in water depend on the "age" (time after dissolution) of the solution. The inconsistencies among the spectroscopic data found in literature, as also the discrepancies with our own measurements on PTAA-based systems are discussed.
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Effect of Ethynyl and 2-Thienyl Substituents on the Complexation of 4′-Substituted 2,2′:6′,2″-Terpyridines with Zn2+ and Fe2+ Ions, and the Spectroscopic Properties of the Ligands and Formed Complex Species. Eur J Inorg Chem 2012. [DOI: 10.1002/ejic.201200256] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Structural and spectroscopic characteristics of [Ni{(Ph2P)2N-S-CHMePh-P,P′}X2], X=Cl, Br: Catalytic activity and selectivity in Kumada and Suzuki–Miyaura coupling reactions. Inorganica Chim Acta 2012. [DOI: 10.1016/j.ica.2012.02.033] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Poly(disubstituted acetylene)s With Pendant Naphthalimide-Based Fluorophore Groups. MACROMOL CHEM PHYS 2012. [DOI: 10.1002/macp.201100509] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Polyacetylene-Type Networks Prepared by Coordination Polymerization of Diethynylarenes: New Type of Microporous Organic Polymers. Macromol Rapid Commun 2011; 33:158-63. [DOI: 10.1002/marc.201100599] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2011] [Revised: 10/17/2011] [Indexed: 11/10/2022]
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H NMR Study of Molecular Weight and Configurational Stability of Poly(2,4-difluorophenylacetylene) and Polyphenylacetylene Prepared with Rh Catalyst. MACROMOL CHEM PHYS 2011. [DOI: 10.1002/macp.201100228] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Colloidal systems of silver nanoparticles and high-regioregular cationic polythiophene with ionic-liquid-like pendant groups: Optical properties and SERS. J Colloid Interface Sci 2011; 354:611-9. [DOI: 10.1016/j.jcis.2010.11.047] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2010] [Revised: 11/12/2010] [Accepted: 11/17/2010] [Indexed: 10/18/2022]
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Molecular weight and configurational stability of poly[(fluorophenyl)acetylene]s prepared with metathesis and insertion catalysts. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/pola.24218] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Synthesis and properties of cationic polyelectrolyte with regioregular polyalkylthiophene backbone and ionic-liquid like side groups. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/pola.24085] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Photogeneration of free charge carriers in tenuously packed π conjugated polymer chains. POLYM ADVAN TECHNOL 2010. [DOI: 10.1002/pat.1724] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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