26 results on '"Xiang, Kai"'
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2. Structural Transformations of Cobalt(II) Coordination Polymers Constructed from N,N′-Di-3-pyridyladipoamide and Tetracarboxylic Acids: Disentanglement upon Water Coordination
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Jhy-Der Chen, Yen-Fu Liu, Ji-Hong Hu, Wei-Te Lee, and Xiang-Kai Yang
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chemistry.chemical_classification ,chemistry ,Polymer chemistry ,chemistry.chemical_element ,General Materials Science ,General Chemistry ,Polymer ,Condensed Matter Physics ,Cobalt ,Hydrothermal circulation - Abstract
Hydrothermal reactions of N,N′-di-3-pyridyladipoamide (L) with 1,2,4,5-benzenetetracarboxylic acid (1,2,4,5-H2btec) in water without and with NaOH afforded [Co(L)(1,2,4,5-btec)0.5]n, 1, and [Co(L)(...
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- 2020
3. Eight-Fold Interpenetrating Diamondoid Coordination Polymers for Sensing Volatile Organic Compounds and Metal Ions
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Jhy Der Chen, Yi Ting Lai, Chia Her Lin, Manivannan Govindaraj, Xiang Kai Yang, and Venkatesan Lakshmanan
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chemistry.chemical_classification ,Aqueous solution ,Polymers and Plastics ,Coordination polymer ,Metal ions in aqueous solution ,Organic chemistry ,General Chemistry ,Polymer ,crystal structure analysis ,Diamondoid ,Article ,chemistry.chemical_compound ,coordination polymer ,QD241-441 ,chemistry ,Polymer chemistry ,luminescence ,Molecule ,Luminescence ,entanglement ,Mesitylene - Abstract
Reactions of divalent metal salts with 4,4-oxybis(N-(pyridine-4-yl)-benzamide), L, and naphthalene-1,4-dicarboxylic acid (1,4-H2NDC) in various solvents gave [Zn(L)(1,4-NDC)·H2O]n, 1, [Cd(L)(1,4-NDC)(H2O)·MeOH]n, 2, and [Co(L)(1,4-NDC)(H2O)0.5·MeOH]n, 3, which have been structurally characterized. Complexes 1–3 show eight-fold interpenetrating frameworks with the dia topology, which exhibit porosities substantiated by CO2 adsorption, whereas 1 and 2 manifest stability in aqueous environments and show high selectivity toward sensing of mesitylene molecules and Fe3+ ions with low detection limits and good reusability up to five cycles.
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- 2021
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4. Entanglement and Irreversible Structural Transformation in Co(II) Coordination Polymers Based on Isomeric Bis-pyridyl-bis-amide Ligands
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Wei-Chun Huang, Chih-Tung Yang, Pradhumna Mahat Chhetri, Xiang-Kai Yang, Chih-Hsun Hsu, and Jhy-Der Chen
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chemistry.chemical_classification ,010405 organic chemistry ,Chemistry ,Structural diversity ,General Chemistry ,Quantum entanglement ,Polymer ,010402 general chemistry ,Condensed Matter Physics ,01 natural sciences ,Structural transformation ,0104 chemical sciences ,Crystallography ,chemistry.chemical_compound ,Amide ,Atom ,General Materials Science ,Single crystal ,Topology (chemistry) - Abstract
Four coordination polymers constructed from the flexible isomeric bis-pyridyl-bis-amide (bpba) ligands, N,N′-di(3-pyridyl)suberoamide (L1) and N,N′-di(4-pyridyl)suberoamide (L2), and the auxiliary 1,4-naphthalenedicarboxylic acid (1,4-H2NDC), including [Co(L1)1.5(1,4-NDC)(H2O)]n, 1, [Co3(L1)1.5(1,4-NDC)3(EtOH)]n, 2, {[Co(L2)1.5(1,4-NDC)]·H2O}n, 3, and {[Co(L2)0.5(1,4-NDC)]·EtOH}n, 4, have been synthesized and structurally characterized by using single crystal X-ray crystallography. Complex 1 forms a two-dimensional layer with double edges and 2 exhibits a unique three-dimensional (3D) self-catenated framework with the (48.66.8)-6T60 topology, while 3 displays a 3D framework with the highest 5-fold interpenetration for the bnn topology and 4 shows a 3D 2-fold interpenetrated framework with the pcu topology. The donor atom positions of the L1 and L2 ligands and the identity of the solvents play important roles in determining the structural diversity. Moreover, irreversible structural transformation from 2 t...
- Published
- 2019
5. Crystal-to-crystal transformation and linker exchange in Cd(<scp>ii</scp>) coordination polymers based on flexible bis-pyridyl-bis-amide and 1,4-naphthalenedicarboxylate
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Xiang-Kai Yang and Jhy-Der Chen
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Crystal transformation ,chemistry.chemical_classification ,Coordination polymer ,Ligand ,General Chemistry ,Polymer ,Condensed Matter Physics ,Crystal ,chemistry.chemical_compound ,Crystallography ,Oxygen atom ,chemistry ,Amide ,General Materials Science ,Linker - Abstract
Solvothermal reactions of Cd(II) salts and naphthalene-1,4-dicarboxylic acid (1,4-H2NDC) with bis(N-pyrid-3-ylmethyl)adipoamide, L1, and bis(N-pyrid-3-ylmethyl)suberoamide, L2, afforded three Cd(II) coordination polymers, {[Cd(L1)(1,4-NDC)(H2O)]·H2O}n, 1, {[Cd(L2)(1,4-NDC)]·2H2O}n, 2, and {[Cd2(L2)(1,4-NDC)2]·3H2O}n, 3, which have been structurally characterized using single-crystal X-ray crystallography. Complex 1 forms a 2D layer with 44-sql topology, whereas 2 and 3 are 3D frameworks with rare {32·62·72}{32·65·73}2-4,5T61 and unique {32·54}{34·46·58·66·74}-sqc776 topologies, respectively. Complex 2 undergoes reversible crystal-to-crystal transformation to 3, while irreversible structural transformations from 1 to 2 and 3 to 1 can be carried out by linker exchange. Reorientation of the amide oxygen atoms that results in the change of the ligand conformation is proposed for the initiation of the crystal-to-crystal transformation. Complex 3 represents a unique example of a coordination polymer that is able to undergo both crystal-to-crystal transformation and linker exchange.
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- 2019
6. Synthesis, crystal structures and thermal properties of six Co(II) and Ni(II) coordination polymers with mixed ligands: Formation of a quadruple-strained helical nanotube
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Chih-Tung Yang, Miao-Ning Chang, Jhy-Der Chen, Meng-Lun Wu, Jo-Feng Hsing, Chih-Hsun Hsu, and Xiang-Kai Yang
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chemistry.chemical_classification ,Nanotube ,Ligand ,Chemistry ,Hydrogen bond ,Organic Chemistry ,02 engineering and technology ,Crystal structure ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,Inorganic Chemistry ,Isophthalic acid ,Metal ,Crystallography ,chemistry.chemical_compound ,visual_art ,visual_art.visual_art_medium ,0210 nano-technology ,Spectroscopy ,Topology (chemistry) - Abstract
The syntheses, structures and thermal properties of six coordination polymers based on semi-rigid N,N′-bis(3-pyridinyl)terephthalamide (L1), flexible N,N′-di(3-pyridyl)adipoamide (L2) and N,N′-di(3-pyridyl)suberoamide (L3) and auxiliary dicarboxylate ligands, [M(L1)(AIPA)·2H2O]n, (M = Ni, 1; Co, 2; H2AIPA = 5-acetamido isophthalic acid), [Ni(L2)(AIPA)(H2O)2]n, 3, [Co(L2)0.5(AIPA)(H2O)]n, 4, [Co(L3)(2,4-PDC)(H2O)]n (2,4-H2PDC = 2,4-pyridinedicarboxylic acid), 5, and [Co(L3)(5-Br-IPA)(H2O)]n (5-Br H2IPA = 5-bromoisophthalic acid), 6, are reported, which have been structurally characterized by X-ray crystallography. Complexes 1 and 2 are isomorphous, forming 3D nets with the new (4⋅6⋅8)(4⋅64⋅85) topology, which can be further simplified as self-catenated networks with the (424⋅64)-8T2 topology, while 3 is a 1D looped chain and 4 and 6 show 2D layers with the (42⋅63⋅8)(42⋅6)-3,4L83 and (44⋅62)-sql topologies, respectively. Moreover, complex 5 shows quadruple-strained helices formed by cobalt ions and L3 ligands, which are supported by 2,4-PDC2- anions to construct the rare single-walled metal-organic nanotubes that are supported by extensive N H --O and O H --O hydrogen bonds. The roles of ligand flexibility and the identity of the metal ion in the formation of 1–6 as well as their thermal properties are discussed.
- Published
- 2018
7. Au(I) and Ag(I) formamidinate tetranuclear complexes and coordination polymers: Synthesis, structures and luminescent properties
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Shi-Jie Lin, Jhy-Der Chen, Wayne Hsu, Yu-Sian Li, Tsun-Ren Chen, Pradhumna Mahat Chhetri, and Xiang-Kai Yang
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chemistry.chemical_classification ,010405 organic chemistry ,Phosphor ,Polymer ,010402 general chemistry ,01 natural sciences ,Fluorescence ,Aurophilicity ,0104 chemical sciences ,Inorganic Chemistry ,Crystallography ,chemistry ,Intramolecular force ,Materials Chemistry ,Physical and Theoretical Chemistry ,Luminescence - Abstract
Reactions of AuClS(CH3)2 and Ag(I) salts (AgSCN, AgOAc and AgSbF6) with the lithiated formamidines afforded the tetranuclear complexes [Au4(4-pyf)4]·4CH3OH [4-Hpyf = N,N’-bis(pyridine-4-yl)formamidine], 1, [Au4(pmf)4] [Hpmf = N,N’-bis(pyrimidine-2-yl)formamidine], 2, and [Ag4(pmf)4], 3, and the coordination polymers [Ag2(OAc)(4-pyf)]n, 4, and {[Ag2(4-pyf)2]·THF}n, 5, which have been structurally characterized by X-ray crystallography. The intramolecular Au⋯Au separations in 1 and 2 are in the range 2.8832(2)–3.3338(10) A and the Ag⋯Ag separations in 3–5 are 2.7927(3)–2.9819(19) A, indicating the existence of aurophilicity and argentophilicity, respectively. Complex 3 is a unique tetranuclear complex of the type Ag4(form)4 in which “form” represents the formamidinate ligands. The short lifetimes of 1.06–49.15 ns for 1–5 indicate that the emissions belong to fluorescence. Moreover, complex 4 emits white luminescence in the solid-state and the CIE coordinate appears at (0.30, 0.38), which represents the first single-emitting component white phosphor in the class of formamidinate coordination polymers.
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- 2018
8. Impact of Isomeric Dicarboxylate Ligands on the Formation of One-Dimensional Coordination Polymers and Metallocycles: A Novel cis→trans Isomerization
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Xiang-Kai Yang, Ji-Hong Hu, Jhy-Der Chen, and Kuan-Ting Chen
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chemistry.chemical_classification ,Polymers and Plastics ,Coordination polymer ,Supramolecular chemistry ,General Chemistry ,Polymer ,structural transformation ,dinuclear metallocycle ,Article ,Cis trans isomerization ,lcsh:QD241-441 ,Crystallography ,chemistry.chemical_compound ,coordination polymer ,Zigzag ,chemistry ,lcsh:Organic chemistry ,X-ray structure ,Single crystal ,Isomerization ,Cis–trans isomerism - Abstract
A series of Co(II), Ni(II) and Cu(II) coordination polymers and dinuclear metallocycles containing 4-aminopyridine (4-ampy) and benzenedicarboxylate ligands, {[M(4-ampy)2(1,4-BDC)]·, H2O·, CH3CH2OH}n (M = Ni, 1a, Co, 1b, 1,4-H2BDC = benzene-1,4-dicarboxylic acid), {[Ni2(4-ampy)4(1,3-BDC)2]·, CH3CH2OH}n (1,3-H2BDC = benzene-1,3-dicarboxylic acid), 2, [M2(4-ampy)4(1,2-BDC)2] (M = Ni, 3a, Co, 3b, 1,2-H2BDC = benzene-1,2-dicarboxylic acid), [Co(4-ampy)2(1,3-BDC)]n, 4, {[Cu(4-ampy)2(1,4-BDC)] CH3CH2OH}n, 5a, and {[Cu(4-ampy)2(1,4-BDC)]·, H2O}n, 5b·, H2O, are reported, which were hydrothermally prepared and structurally characterized by using single crystal X-ray diffraction. Complexes 1a and 1b are isomorphous 1D zigzag chains, while 2 displays a concave&ndash, convex chain and 3a and 3b are dinuclear metallocycles that differ in the boding modes of the 1,2-BDC2&minus, ligands, forming a 3D and a 2D supramolecular structures with the pcu and sql topologies, respectively. Complex 4 exhibit a 1D helical chain and complexes 5a and 5b·, H2O are 1D linear and zigzag chains, in which the Cu2-1,4-BDC2&minus, units adopt the cis and trans configurations, respectively. A novel irreversible structural transformation due to cis&rarr, trans isomerization of the Cu2-1,4-BDC2&minus, units was observed in 5b&sdot, H2O and 5a upon water adsorption of the desolvated product of 5b·, H2O.
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- 2020
9. Co(II) coordination polymers exhibiting reversible structural transformation and color change: A comparative analysis with Ni(II) analogue
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Kedar Bahadur Thapa, Tsun-Ren Chen, Jhy-Der Chen, Ming-Hao Wu, and Xiang-Kai Yang
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Diffraction ,chemistry.chemical_classification ,02 engineering and technology ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Net (mathematics) ,01 natural sciences ,Structural transformation ,0104 chemical sciences ,Inorganic Chemistry ,Crystallography ,chemistry ,Materials Chemistry ,Physical and Theoretical Chemistry ,0210 nano-technology ,Single crystal ,Topology (chemistry) - Abstract
By employing the flexible ligands, bis(3,5-dicarboxyphenyl)adipoamide, H4L1; bis(N-pyrid-3-ylmethyl)adipoamide, L2; and bis(N-pyrid-3-ylmethyl) suberoamide, L3, four coordination polymers of the types {[M(L1)0.5(L2)(H2O)2]·H2O}n (M = Co, 1; Ni, 2) and {[M2(L1)(L3)2(H2O)4]·3H2O}n (M = Co, 3; Ni, 4) have been hydrothermally synthesized and structurally characterized by single crystal X-ray diffraction. Complexes 1–4 are topologically identical coordination polymers having the 2-fold interpenetrating 3D net with the mog topology. Additionally, the Co(II) complexes exhibit the reversible structural transformation with color change on dehydration/rehydration but Ni(II) complexes are unable to show such a behavior. All four complexes display good photo-degradation performance and the Co(II) complexes show slightly higher efficiencies than the Ni(II) ones.
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- 2018
10. Mercury halide coordination polymers exhibiting reversible structural transformation
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Jhy-Der Chen, Pradhumna Mahat Chhetri, and Xiang-Kai Yang
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chemistry.chemical_classification ,010405 organic chemistry ,Chemistry ,Halide ,General Chemistry ,Polymer ,010402 general chemistry ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,Solvent ,chemistry.chemical_compound ,Crystallography ,Amide ,General Materials Science ,Isostructural ,Luminescence ,Acetonitrile ,Acetamide - Abstract
Solvothermal reactions of HgX2 salts with the new bis-pyridyl-bis-amide ligand 2,2′-(1,3-phenylene)-bis(N-(pyridin-3-yl)acetamide) (1,3-pbpa) in acetonitrile afforded the complexes [Hg(1,3-pbpa)X2]n (X = Cl, 1; Br, 2; I, 3), while the complexes [Hg(1,3-pbpa)X2·MeCN]n (X = Br, 4; I, 5) were obtained by layering solutions of HgX2 and 1,3-pbpa at room temperature. Complexes 1 and 2 are isostructural one-dimensional (1D) helical chains different from the 1D helical chain 3 in spans, which are 18.0, 18.3 and 29.1 A, respectively. Upon solvent adoption and removal, complexes 2 and 3 undergo reversible structural transformation into the 1D mesohelical chains 4 and 5 with spans of 29.1 and 29.9 A, respectively. Pyridyl ring rotation and amide group reorientation are proposed for the structural transformation accompanied by a simultaneous change in luminescence. The structural transformation in 2 and 4 represents a unique example of elastic 1D helical chains that show stretching during the process. The roles of halide anions in the structural changes and the luminescence properties of 1–5 are also discussed.
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- 2018
11. Isostructural Hg(II) halide coordination polymers: A comparison of powder XRD, IR, emission and Hirshfeld Surface Analysis
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Pradhumna Mahat Chhetri, Xiang-Kai Yang, and Jhy-Der Chen
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chemistry.chemical_classification ,Bromine ,010405 organic chemistry ,Organic Chemistry ,Halide ,chemistry.chemical_element ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,Inorganic Chemistry ,Solvent ,Crystallography ,chemistry ,Molecule ,Non-covalent interactions ,Isostructural ,Luminescence ,Spectroscopy ,Powder diffraction - Abstract
Three isomorphous mercury(II) halide coordination polymers [Hg(dpndc)X2]n (X = Cl, 1; Br, 2; I, 3) have been synthesized by the reactions of HgX2 salts with the semi-rigid N,N’-di(pyridin-3-yl)naphthalene-1,4-dicarboxamide (dpndc), which form one-dimensional (1D) helical chains. Stuctural comparisons with the other similar CPs indicate that their structural diversity is governed by the co-crystallized solvent molecules and the identity of the spacer ligands, whereas the role of the halide anions is not significant. Hirshfeld Surface Analysis revels that chlorine atom contributes more non-covalent interactions compared to the bromine and iodine atoms. Complexes 1 - 3 provide a unique opportunity to demonstrate that the powder X-ray diffraction (PXRD) pattern is better than IR and emission spectra to differentiate isomorphous mercury(II) halide CPs.
- Published
- 2021
12. Substituent effects of polycarboxylate ligands on the construction of Cd(II) coordination polymers incorporating bis-pyridyl-bis-amide ligands
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Hsiu-Yi He, Pradhumna Mahat Chhetri, Xiang-Kai Yang, Chih-Hsun Hsu, Miao-Ning Chang, and Jhy-Der Chen
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chemistry.chemical_classification ,010405 organic chemistry ,Chemistry ,Coordination polymer ,Ligand ,Stereochemistry ,Substituent ,Polymer ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Inorganic Chemistry ,Crystallography ,chemistry.chemical_compound ,Amide ,Materials Chemistry ,Physical and Theoretical Chemistry ,Luminescence ,Single crystal ,Topology (chemistry) - Abstract
The synthesis, structures and properties of five new coordination polymers containing isomeric N,N′-di(pyridyl)suberoamide and polycarboxylate ligands, {[Cd(1,3-BDC)(L1)]·H2O}n [L1 = N,N′-di(3-pyridyl)suberoamide; 1,3-H2BDC = benzene-1,3-dicarboxylic Acid] 1; [Cd(5-OH-IPA)(L1)]n (5-OH-IPA = 5-hydroxyisophthalic Acid), 2; {[Cd3(1,3,5-BTC)2(L1)3(H2O)3]·8H2O}n (1,3,5-H3BTC = 1,3,5-benzenetricarboxylic Acid), 3; [Cd(5-Br-IPA)(L2)]n [L2 = N,N′-di(4-pyridyl)suberoamide; 5-Br-H2IPA = 5-bromoisophthalic Acid], 4; [Cd(5-tert-IPA)(L2)0.5]n (5-tert-H2IPA = 5-tert-butylisophthalic acid), 5, are reported, which have been characterized by single crystal X-ray diffraction. Complexes 1 and 2 show 2D double layers with the 3,5L2 topology and 3 reveals a 3D structure with the rare 3,4,4T90 topology. Complex 4 is a twofold interpenetrated 2D layer with a 2,6L1 topology and 5 shows a 3D coordination network with a rare 4,6T136 topology. In 5, the L2 ligand adopts a unique tetradentate bonding mode through two pyridyl nitrogen and two amide oxygen atoms. The structure-directing role roles of the substituent groups on the polycarboxylate ligands in determining the structural diversity are discussed. Their thermal and luminescent properties are also investigated.
- Published
- 2017
13. Solvent-Mediated Reversible Structural Transformation of Mercury Iodide Coordination Polymers: Role of Halide Anions
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Jhy-Der Chen, Pradhumna Mahat Chhetri, and Xiang-Kai Yang
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chemistry.chemical_classification ,010405 organic chemistry ,Chemistry ,Inorganic chemistry ,Iodide ,Halide ,General Chemistry ,010402 general chemistry ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,Solvent ,chemistry.chemical_compound ,Crystallography ,Adsorption ,General Materials Science ,Methanol ,Isostructural ,Acetonitrile ,Acetamide - Abstract
Solvothermal reactions of HgX2 with 2,2′-(1,2-phenylene)-bis(N-pyridin-3-yl)acetamide, L, in ethanol afforded [Hg(L)X2]n (X = Cl, 1; Br, 2; I, 3), which are isostructural one-dimensional (1D) zigzag chains, while layering reactions of a ethanoic solution of L with a methanoic solution and an acetonitrile solution of HgI2, respectively, gave 1D helical chains [Hg(L)I2·MeOH]n, 4, and [Hg(L)I2·MeCN]n, 5. In marked contrast to 1 and 2, the iodide-containing 3 is able to exhibit reversible structural transformation with 4 and 5 by adsorption and desorption of methanol and acetonitrile, suggesting the importance of N–H---X and Hg---X interactions in the evaluation of structural transformation. Moreover, complexes 4 and 5 exhibit reversible crystal to crystal transformation triggered by solvent exchange. Complexes 3–5 represent a unique example that the solvents show a significant effect on folding and unfolding of the HgI2 single-stranded helical coordination polymers.
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- 2017
14. Structure-directing roles of phenylenediacetate ligands in the formation of N,N′-di(3-pyridyl)adipoamide-based coordination networks
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Pradhumna Mahat Chhetri, Jhy-Der Chen, Chin-Hsueh Chen, Xiang-Kai Yang, Yen-Fu Liu, and Han-Yun Chang
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chemistry.chemical_classification ,010405 organic chemistry ,Metal ions in aqueous solution ,Iodide ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Inorganic Chemistry ,Electronegativity ,Crystallography ,chemistry.chemical_compound ,chemistry ,Bromide ,X-ray crystallography ,Bathochromic shift ,Materials Chemistry ,Molecule ,Physical and Theoretical Chemistry ,Single crystal - Abstract
A series of coordination networks constructed from divalent metal ions, N,N′-di(3-pyridyl)adipoamide (L) and phenylenediacetate ligands, including [Co(L)0.5(1,2-pda)(H2O)]n (1,2-H2pda = 1,2-phenylenediacetic acid), 1, [Co(L)(1,4-pda)]n (1,4-H2pda = 1,4-phenylenediacetic acid), 2, [Ni2(L)2(1,2-pda)2(H2O)2·4.5H2O]n, 3, [Ni(L)(1,4-pda)(H2O)0.5·2.5H2O]n, 4, [Zn(L)0.5(1,2-pda)]n, 5, [CdBr(L)(1,2-pda)0.5]n, 6, and [CdI(L)(1,2-pda)0.5]n, 7, have been synthesized by hydrothermal reactions and structurally characterized by single crystal X-ray diffraction. Complexes 1, 2 and 5 adopt the (42,63,8)(42,6)-3,4L83, (42,67,8)(42,6)-3,5L2 and (42,63,8)(42,6)-3,4L83 topologies, respectively, while 3 and 4 show the (48,67)-6T2 and (48,67)-sqc26 topologies, respectively, and both 6 and 7 display the (412,63)-pcu topology. The L ligands in 3 adopt three different conformations, while the pda2− ligands in 5 adopts the rare cis-conformation and those in the other complexes exhibit the trans-conformation. Moreover, the pda2− ligands in complexes 1, 2 and 5 display the μ3 bonding mode to afford the 2D layer structures, in contrast to those in the other complexes that show the μ4 and/or μ2 bonding modes to form the 3D frameworks. The conformations of the L ligands are subject to the changes of metal ions and pda2− ligands, resulting in various types of structure for 1–7. Temperature-dependent PXRD patterns of complexes 1, 3 and 4 indicate that their structural transformations upon removal of the water molecules are irreversible. The emission spectra of 6 and 7 reveal that the lower electronegativity of the iodide relative to the bromide has a significant effect on the bathochromic shift.
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- 2016
15. Dinitrogen-supported coordination polymers
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Xiang-Kai Yang, Kedar Bahadur Thapa, Jhy-Der Chen, Wayne Hsu, Kuan-Ting Chen, and Han-Yun Chang
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chemistry.chemical_classification ,Binodal ,010405 organic chemistry ,Stereochemistry ,General Chemistry ,Polymer ,010402 general chemistry ,Condensed Matter Physics ,Triethyl orthoformate ,01 natural sciences ,Medicinal chemistry ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Pyridine ,General Materials Science ,Methanol ,Topology (chemistry) - Abstract
The one-pot solvothermal reactions of 3- and 4-(aminomethyl)pyridine with triethyl orthoformate and Cu(O2CCH3)2 in methanol saturated with dinitrogen afforded the first examples of coordination polymers that are supported by dinitrogen, namely [Cu2.5(3-mpyf)(N2)1.5]n [3-Hmpyf = N,N′-bis(pyridine-3-ylmethyl)formamidine], 1, and {[Cu3(4-Hmpyf)(N2)3]·(CH3OH)}n [4-Hmpyf = N,N′-bis(pyridine-4-ylmethyl)formamidine], 2. The dinitrogen anions of 1 adopt the end-on-dinuclear (μ-η1:η1) bonding mode, resulting in a 4,4-connected binodal net with the new (53·73)2(54·82) topology, and those of 2 display both end-on-dinuclear and end-on-trinuclear (μ-η1:η1:η1) bonding modes, forming a 3,8-connected binodal net with the rare (53)4(58·64·78·84·94)2-3,8T16 topology.
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- 2016
16. Mg(II) Coordination Polymers Based on Flexible Isomeric Tetracarboxylate Ligands: Syntheses, Structures, Structural Transformation and Luminescent Properties
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Jhy-Der Chen, Kedar Bahadur Thapa, and Xiang-Kai Yang
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Polymers and Plastics ,Coordination polymer ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Hydrothermal circulation ,Article ,Ion ,lcsh:QD241-441 ,chemistry.chemical_compound ,lcsh:Organic chemistry ,Topology (chemistry) ,chemistry.chemical_classification ,Chemistry ,Ligand ,General Chemistry ,Polymer ,structural transformation ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Solvent ,Crystallography ,coordination polymer ,tetracarboxylate ,X-ray structure ,0210 nano-technology ,Luminescence - Abstract
By using a new flexible tetracarboxylic acid, bis(3,5-dicarboxyphenyl) adipoamide, H4L1, and its isomer, bis(2,5-dicarboxyphenyl)adipoamide, H4L2, three Mg(II) coordination polymers, {[Mg2(L1)(H2O)2]·2EtOH·3H2O}n, 1, [Mg2(L1)(H2O)8]n, 2, and {[Mg2(L2)(H2O)6]·H2O}n, 3, have been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Complexes 1 and 2 are the solvent ratio-dependent hydrothermally stable products. The tetracarboxylate ligand of complex 1 connects eight Mg(II) ions through nine oxygen atoms, resulting in a three-dimensional (3D) 5-connected uninodal net with a rare non-interpenetrating (44.66)-pcu-5-Pmna topology, whereas those of 2 and 3 link four Mg(II) ions through four oxygen atoms and six Mg(II) ions through six oxygen atoms, forming a 1D linear chain and a 3,6-connected 2-nodal 3D net having {4.62}2{42.610.83}-rtl topology, respectively. Complex 1 shows a series of structural transformations on heating to 200 °C and almost reversible structural transformation when the activated products were immersed in a mixture of ethanol and water or on hydrothermal. Likewise, complex 2 exhibits a reversible structural transformation on heating/hydrothermal, while 3 exhibits irreversible structural transformations. All three complexes exhibit blue light emissions, with that of complex 3 being much more intense.
- Published
- 2018
17. Metal and Ligand Effects on the Construction of Divalent Coordination Polymers Based on bis-Pyridyl-bis-amide and Polycarboxylate Ligands
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Pradhumna Mahat Chhetri, Xiang-Kai Yang, Miao-Ning Chang, and Jhy-Der Chen
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Polymers and Plastics ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Article ,Divalent ,Isophthalic acid ,Metal ,Ligand isomerism ,lcsh:QD241-441 ,chemistry.chemical_compound ,lcsh:Organic chemistry ,Amide ,chemistry.chemical_classification ,Ligand ,Center (category theory) ,General Chemistry ,021001 nanoscience & nanotechnology ,polycarboxylate ,0104 chemical sciences ,Crystallography ,coordination polymer ,bis-pyridyl-bis-amide ,chemistry ,visual_art ,visual_art.visual_art_medium ,photodegradation ,0210 nano-technology ,Luminescence - Abstract
Ten coordination polymers constructed from divalent metal salts, polycarboxylic acids, and bis-pyridyl-bis-amide ligands with different donor atom positions and flexibility are reported. They were structurally characterized by single-crystal X-ray diffraction. The ten coordination polymers are as follows: (1) {[Ni(L1)(3,5-PDA)(H2O)3]·2H2O}n (L1 = N,N′-di(3-pyridyl)suberoamide, 3,5-H2PDA = 3,5-pyridinedicarboxylic acid); (2) {[Ni2(L1)2(1,3,5-HBTC)2(H2O)4]·H2O}n (1,3,5-H3BTC = 1,3,5-benzenetricarboxylic acid); (3) {[Ni(L2)(5-tert-IPA)(H2O)2]·2H2O}n (L2 = N,N′-di(3-pyridyl)adipoamide, 5-tert-H2IPA = 5-tert-butylisophthalic acid); (4) [Ni(L3)1.5(5-tert-IPA)]n (L3 = N,N′-di(4-pyridyl)adipoamide); (5) [Co(L1)(1,3,5-HBTC)(H2O)]n; (6) {[Co3(L1)3(1,3,5-BTC)2(H2O)2]·6H2O}n; (7) [Cu(L4)(AIPA)]n (L4 = N,N′-bis(3-pyridinyl)terephthalamide, H2AIPA = 5-acetamido isophthalic acid); (8) {[Cu(L2)0.5(AIPA)]·MeOH}n; (9) {[Zn(L4)(AIPA)]·2H2O}n; and (10) {[Zn(L2)(AIPA)]·2H2O}n. Complex 1 forms a 1D chain and 2 is a two-fold interpenetrated 2D layer with the sql topology, while 3 is a 2D layer with the hcp topology and 4 shows a self-catenated 3D framework with the rare (42·67·8)-hxg-d-5-C2/c topology. Different Co/1,3,5-H3BTC ratios were used to prepare 5 and 6, affording a 2D layer with the sql topology and a 2D layer with the (4·85)2(4)2(83)2(8) topology that can be further simplified to an hcp topology. While complex 7 is a 2D layer with the (42·67·8)(42·6)-3,5L2 topology and 8 is a 2-fold interpenetrated 3D framework with the pcu topology, complexes 9 and 10 are self-catenated 3D frameworks with the (424·64)-8T2 and the (44·610·8)-mab topologies, respectively. The effects of the identity of the metal center, the ligand isomerism, and the flexibility of the spacer ligands on the structural diversity of these divalent coordination polymers are discussed. The luminescent properties of 9 and 10 and their photocatalytic effects on the degradation of dyes are also investigated.
- Published
- 2017
18. One-Dimensional Mercury Halide Coordination Polymers Based on A Semi-Rigid N-Donor Ligand: Reversible Structural Transformation
- Author
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Jhy-Der Chen, Pradhumna Mahat Chhetri, Chih-Tung Yang, and Xiang-Kai Yang
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chemistry.chemical_classification ,Polymers and Plastics ,Coordination polymer ,Halide ,chemistry.chemical_element ,General Chemistry ,Polymer ,structural transformation ,mercury halide ,Structural transformation ,Mercury (element) ,lcsh:QD241-441 ,coordination polymer ,bis-pyridyl-bis-amide ,Crystallography ,chemistry.chemical_compound ,lcsh:Organic chemistry ,chemistry ,Acetamide - Abstract
Four one-dimensional (1D) mercury(II) halide coordination polymers have been synthesized by using a semi-rigid N-donor ligand, 2,2&prime, (1,4-phenylene)-bis(N-(pyridin-3-yl)acetamide) (1,4-pbpa). While [Hg(1,4-pbpa)Cl2·, CH3OH]n, 1, forms a sinusoidal chain, the complexes [Hg(1,4-pbpa)X2]n (X = Cl, 2, Br, 3, I, 4) are helical. The sinusoidal 1 undergoes reversible structural transformation with helical 2 upon removal and uptake of CH3OH, which was accompanied with the conformation adjustment of the 1,4-pbpa ligand from trans anti-anti to trans syn-anti. Pyridyl ring rotation of the 1,4-pbpa ligand that results in the change of the ligand conformation is proposed for the initiation of the structural transformation.
- Published
- 2019
19. Exploration of the Structures of the Magnetically Induced Self-Assembly Photonic Crystals in a Solidified Polymer Matrix
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Hai Bo Hu, Xiang Kai Kong, Qianwang Chen, Ran Li, and Jian Chen
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chemistry.chemical_classification ,Polyacrylamide Hydrogel ,Colloid ,Materials science ,Nanostructure ,chemistry ,General Engineering ,Nanotechnology ,Self-assembly ,Polymer ,Magnetic field ,Superparamagnetism ,Photonic crystal - Abstract
The carbon-encapsulated superparamagnetic colloidal nanoparticles (SCNps) were rigidized into soft solids by embedding the SCNps into polyacrylamide hydrogel matrixes under the induction of an external magnetic field. Stabilized by the balance of attractive (magnetic) and repulsive (electrostatic) forces, the SCNps form one-dimension photonic crystal structures along the direction of the external magnetic field and further the structures are frozen into the solidified polymer matrix. The polymer matrix embedded one-dimension photonic crystal structures can strongly diffract visible light and present brilliant color in the light. This novel and soft solid polymer matrix that could be shaped and sliced not only paves a new avenue for develop novel magnetic-responsive photonic crystal materials and devices, but also provides a method to observe the magnetic-induced self-assembly structures of the SCNps in media such as polyacrylamide hydrogel matrixs as a result of the ordered structures frozen into the polyacrylamide hydrogel matrixs. So we can reveal the relationship between their structure and color, and furthermore permit a systematic exploration on magnetically induced self-assembling dynamics, colloidal crystallography which have important significance in the large-scale industrial production in the future.
- Published
- 2013
20. Spectroscopic and electrochemical studies on block-polymer/PMMA blend based composite polymer electrolytes
- Author
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Xiang-kai Fu, Yongfeng Gong, and Shupeng Zhang
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chemistry.chemical_classification ,Materials science ,Nanocomposite ,Polymers and Plastics ,General Chemistry ,Polymer ,Electrolyte ,Lithium perchlorate ,Polyelectrolyte ,Surfaces, Coatings and Films ,chemistry.chemical_compound ,Chemical engineering ,chemistry ,Polymer chemistry ,Materials Chemistry ,Ionic conductivity ,Thermal stability ,Polymer blend - Abstract
Poly(methylmethacrylate)(PMMA)/oxymethylene-linked polyoxyethylene multi-block polymer(Om-POEn, where n represents number of unit CH2CH2O) blend based composite electrolyte films containing different lithium salt concentration and nanofillers' content are prepared using solvent evaporation technique. The interaction of polymer–salt complex has been confirmed using FTIR spectral studies. The figuration of CPE was studied by XRD. Ionic conductivity and thermal behavior of the CPEs were studied with various salt concentrations, temperature, and nanofillers' content. The surface structure of the CPE is also investigated using scanning electron microscopy. The high room temperature ionic conductivity, transmittivity in the visible region, and thermal stability make these CPEs potential candidates as solid-like electrolytes for electrochemical devices. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
- Published
- 2007
21. Preparation of a Star Network PEG-based Gel Polymer Electrolyte and Its Application to Electrochromic Devices
- Author
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Shu-Peng Zhang, Xiang-Kai Fu, Yong-Feng Gong, and Qinglong Jiang
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chemistry.chemical_classification ,General Chemistry ,Polymer ,Electrolyte ,Electrochromic devices ,Pentaerythritol ,Lithium perchlorate ,Thermogravimetry ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,Polymer chemistry ,Ionic conductivity ,Thermal stability - Abstract
A star network polymer with a pentaerythritol core linking four PEG-block polymeric arms was synthesized, and its corresponding gel polymer electrolyte based on lithium perchlorate and plasticizers EC/PC with the character being colorless and highly transparent has been also prepared. The polymer host was characterized and confirmed to be of a star network and an amorphous structure by FTIR, 1H NMR and XRD studies. The polymer host hold good mechanical properties for pentaerythritol cross-linking. Maximum ionic conductivity of the prepared polymer electrolyte has reached 8.83×10−4 S·cm−1 at room temperature. Thermogravimetry (TG) of the polymer electrolyte showed that the thermal stability was up to at least 150 °C. The gel polymer electrolyte was further evaluated in electrochromic devices fabricated by transparent PET-ITO and electrochromically active viologen derivative films, and its excellent performance promised the usage of the gel polymer electrolyte as ionic conductor material in electrochromic devices.
- Published
- 2007
22. Synthesis of the novel layered amorphous and crystalline zirconium phosphate–phosphonates Zr(HPO4)[O3PCH2N(CH2CH2)2O]·nH2O, Zr(HPO4)[O3PCH2N(CH2CO2H)2]·nH2O, zirconium phosphonates Zr[(O3PCH2)NCH2CO2H]·nH2O and the catalytic activities of their palladium complexes in hydrogenation
- Author
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Ma Xue-Bing and Fu Xiang-Kai
- Subjects
chemistry.chemical_classification ,Zirconium ,Double bond ,Chemistry ,Process Chemistry and Technology ,Inorganic chemistry ,chemistry.chemical_element ,Crystal structure ,Catalysis ,Amorphous solid ,chemistry.chemical_compound ,Hydrofluoric acid ,Zirconium phosphate ,Physical and Theoretical Chemistry ,Nuclear chemistry ,Palladium - Abstract
The layered amorphous and crystalline samples of zirconium [ N -(phosphonomethyl)morpholine-phosphate] Zr(HPO 4 )[O 3 PCH 2 N(CH 2 CH 2 ) 2 O]· n H 2 O (1a, 2a), zirconium [ N -(phosphonomethyl)iminodiacetic acid-phosphate] Zr(HPO 4 )[O 3 PCH 2 N(CH 2 CO 2 H) 2 ]· n H 2 O (1b, 2b) and zirconium [ N , N -di(phosphonomethyl) acetic acid] Zr[(O 3 PCH 2 ) 2 NCH 2 CO 2 H]· n H 2 O (1c, 2c) were synthesized for the first time with zirconium oxychloride, sodium dihydrogen phosphate and H 2 O 3 PCH 2 N(CH 2 CH 2 ) 2 O, H 2 O 3 PCH 2 N(CH 2 CO 2 H) 2 or (H 2 O 3 PCH 2 ) 2 NCH 2 CO 2 H in the absence and presence of hydrofluoric acid. The samples were comparatively characterized by XRD, IR, TG and elemental analysis. XRD data showed that the crystalline samples 2a, 2b and 2c are highly crystalline with interlayer spacings of 1.606, 1.538 and 1.239 nm, respectively. The amorphous and crystalline samples lost nearly the weight calculated for their organic component over the same broad temperature range of 172–664, 184–680 and 176–668 °C, respectively. XPS data indicated that the coordination bonds formed between nitrogen and palladium in the palladium complexes. Their palladium complexes possessed good activities for the hydrogenation of the carbon–carbon double bond. The catalytic activities of the palladium complexes of amorphous 1a, 1b and 1c is 1.5–3.1 times as high as that of the palladium complexes of crystalline 2a, 2b and 2c.
- Published
- 2004
23. Design, synthesis and biological evaluation of novel 4-hydroxybenzene acrylic acid derivatives
- Author
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Xiang-Kai Ran, Jinlong Mao, Li Chen, Bo Jiao, Hong-Lei Zhou, Zhen-Guo Wang, and Jing-Zhen Tian
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chemistry.chemical_classification ,Double bond ,Coumaric Acids ,Molecular Structure ,Phenol ,Chemistry ,Organic Chemistry ,Clinical Biochemistry ,Anti-Inflammatory Agents ,Pharmaceutical Science ,Phenolic acid ,Biochemistry ,Chemical synthesis ,Sulfone ,Ferulic acid ,chemistry.chemical_compound ,Acrylates ,Drug Design ,Drug Discovery ,Molecular Medicine ,Organic chemistry ,Selectivity ,Benzene ,Molecular Biology ,Acrylic acid - Abstract
A series of 4-hydroxybenzene acrylic acid derivatives were designed and synthesized based on the ferulic acid of natural active ingredients. The tested compound 5a, 5f and 6a have significant anti-inflammatory activity with suppression rates of 45.29%, 44.75% and 24.11%, respectively, compared with that of indomethacin, and their cardiac toxicity was not observed. The structure-function relationship shows that the p-hydroxyl group on the α-position benzene ring, particularly if acetylated, contributes to the considerable anti-inflammatory activity; that the carboxyl group on the double bond, if esterified, also contributes to the anti-inflammatory activity; that the p-methylsulfonyl group on the other benzene ring, whose introduction is due to the COX-2 selectivity, also contributes to anti-inflammatory activity surprisingly.
- Published
- 2010
24. Synthesis of 2′,3′-Dideoxy-2′-trifluoromethyl-N-azanucleosides
- Author
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Jiang Yu, Xiang-Kai Fu, and Feng-Ling Qing
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chemistry.chemical_classification ,Serine ,chemistry.chemical_compound ,Trifluoromethyl ,chemistry ,Stereochemistry ,Trifluoromethylation ,Nucleic acid ,General Chemistry ,General Medicine ,Aldehyde - Abstract
The trifluoromethylation of (Z)/(E)-tert-butyl (4S)-4-(2'-ethoxycarbonyl-2'-bromoprop-1'-enyl)-2,2-dimethyloxazolidine-3-carboxylate (4), which is derived from chiral serine aldehyde, yields α-trifluoromethyl-α,β-unsaturated ester 1. Compound 1 is used as a key intermediate for the synthesis of a number of 2',3'-dideoxy-2'-trifluoromethyl-N-azanucleosides.
- Published
- 2003
25. STUDY ON THE PREPARATION AND PERFORMANCES OF P(VAc-MMA) POLYMER ELECTROLYTES FOR LITHIUM ION BATTERY
- Author
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Xiang-kai Fu, Dao-jun Yang, and Yong-feng Gong
- Subjects
chemistry.chemical_classification ,Materials science ,Polymers and Plastics ,General Chemical Engineering ,Organic Chemistry ,Electrolyte ,Polymer ,Lithium-ion battery ,chemistry.chemical_compound ,Monomer ,chemistry ,Chemical engineering ,Polymer chemistry ,Vinyl acetate ,Copolymer ,Ionic conductivity ,Thermal stability - Abstract
A random copolymer P(VAc-MMA) was synthesized via seeded emulsion copolymerization with vinyl acetate (VAc) and methyl methacrylate (MMA) as monomers, and the polymer electrolytes comprising blend of corresponding copolymer P(VAc-MMA) as a host polymer and LiClO4 as a dopant were prepared by solution casting technique. Performances of the synthesized copolymer and prepared polymer membrane and electrolyte were studied by FTIR, XRD, TG, DSC, mechanical testing and AC impedance. According to the study of FTIR and DSC, it was found that P(VAc-MMA) had been formed. XRD indicates that the amorphous nature in copolymer increased with increasing the ratio of VAc in monomers, resulting in expedite migration of ions. The polymer electrolytes based on P(VAc-MMA) possess excellent thermal stability, fine mechanical performance and high ionic conductivity. The maximum ionic conductivity value was found to reach 1.27 × 10-3S · cm-1 at 25°C. The temperature dependence of the polymer electrolyte complexes appeared to ob...
- Published
- 2008
26. PREPARATION OF STAR NETWORK PEG-BASED GEL POLYMER ELECTROLYTES FOR ELECTROCHROMIC DEVICES
- Author
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Qing-long Jiang, Xiang-kai Fu, Yong-feng Gong, and Shu-peng Zhang
- Subjects
chemistry.chemical_classification ,Materials science ,Polymers and Plastics ,General Chemical Engineering ,Organic Chemistry ,Polymer ,Electrochromic devices ,Pentaerythritol ,Lithium perchlorate ,chemistry.chemical_compound ,chemistry ,Electrochromism ,Propylene carbonate ,Polymer chemistry ,Ethylene glycol ,Ethylene carbonate - Abstract
An amorphous, colorless, and highly transparent star network polymer with a pentaerythritol core linking four PEG-block polymeric arms was synthesized from the poly(ethylene glycol) (PEG), pentaerythritol, and dichloromethane by Williamson reaction. FTIR and 1 H-NMR measurement demonstrated that the polymer repeating units were C(CH2―OCH2O―(CH2CH2O)m―CH2O―(CH2CH2O)n―CH2O)4. The polymer host held well mechanical properties for pentaerythritol cross-linking. The gel polymer electrolytes based on Lithium perchlorate (LiClO4) and ethylene carbonate/propylene carbonate (EC/PC) were prepared and characterized by AC impedance spectroscopy and thermogravimetry (TG), the results showed thermal stability up to at least 150°C and ionic conductivity reaching 8.83 × 10 −4 S·cm −1 at room temperature. The gel polymer electrolytes were further evaluated in electrochromic devices (ECD) fabricated by transparent PET-ITO and electrochromic active viologen derivative films, and its excellent performance promised the usage of the gel polymer electrolytes as ionic conductor material in ECD.
- Published
- 2008
Catalog
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