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1. Conductive polymer preparation under extreme or non-classical conditions

Author:
de Azevedo, W. M.; de Barros, R. A.; da Silva, E. F., Jr
Source:
Journal of materials science 2008 v.43 no.4 pp. 1400-1405
ISSN:
0022-2461
Subject:
X-radiation; ambient temperature; aniline; aqueous solutions; composite materials; gamma radiation; hydrogen; hydroxyl radicals; ions; irradiation; nanosilver; oxidants; polymerization; polymers; reducing agents; scanning electron microscopy; silver; silver nitrate; sonication; spectroscopy; ultrasonic treatment; ultraviolet radiation
Abstract:
... Polyaniline (PANI) emeraldine salt form and PANI/silver composites have been synthesized by sonochemical and ionizing radiation methods. These composite materials were obtained through sonication and γ irradiation of an aqueous solution of aniline and silver nitrate, in room temperature, respectively. The mechanisms suggested to explain the formation of these products are based on the fact that bo ...
DOI:
10.1007/s10853-007-2278-2

2. Hydrogen bond-directed self-assembly of peripherally modified cyclotriphosphazenes with a homeotropic liquid crystalline phase Part A Polymer chemistry

Author:
Xu, Jianwei; Ling, Toh Cher; He, Chaobin
Source:
Journal of polymer science 2008 v.46 no.14 pp. 4691-4703
ISSN:
0887-624X
Subject:
X-radiation; benzoic acids; differential scanning calorimetry; enthalpy; entropy; ethylene; hydrogen; hydrogen bonding; liquid crystals; microscopy; phase transition; polymers; temperature; thermal properties
Abstract:
... The synthesis and characterization of hydrogen-bonded star-shaped complexes consisting of stilbazolyloxy, azopyridyl, and Schiff base-substituted cyclotriphosphazenes (3a, 3b, and 3c, respectively) and monoalkyloxy, bis(dodecyloxy), and tris(dodecyloxy)benzoic acids are reported. The thermal behaviors of complexes are studied by the means of differential scanning calorimetry, polarizing optical mi ...
DOI:
10.1002/pola.22800

3. High-temperature proton exchange membranes based on polybenzimidazole and clay composites for fuel cells

Author:
Plackett, David; Siu, Ana; Li, Qingfeng; Pan, Chao; Jensen, Jens Oluf; Nielsen, Søren Fæster; Permyakova, Anastasia A.; Bjerrum, Niels J.
Source:
Journal of membrane science 2011 v.383 no.1-2 pp. 78-87
ISSN:
0376-7388
Subject:
X-radiation; ambient temperature; artificial membranes; cations; clay; dimensional stability; electric power; fuel cells; hydrogen; hydrogen bonding; infrared spectroscopy; ion exchange; permeability; phosphoric acid; polymers; relative humidity; salts; tensile strength
Abstract:
... Good dispersion of modified laponite clay was achieved in polybenzimidazole (PBI) solutions which, when cast and allowed to dry, resulted in homogeneous and transparent composite membranes containing up to 20wt% clay in the polymer. The clay was organically modified using a series of ammonium and pyridinium salts with varying polarity and hydrogen-bonding capacity. Clay modification by ion-exchang ...
DOI:
10.1016/j.memsci.2011.08.038

4. Polyelectrolyte/fluorinated polymer interpenetrating polymer networks as fuel cell membrane

Author:
Delhorbe, Virginie; Reijerkerk, Sander R.; Cailleteau, Céline; Bathfield, Maël; Chikh, Linda; Gouanve, Fabrice; Ogier, Lionel; Espuche, Eliane; Ameduri, Bruno; Vidal, Serge; Gebel, Gérard; Morin, Arnaud; Fichet, Odile
Source:
Journal of membrane science 2013 v.429 pp. 168-180
ISSN:
0376-7388
Subject:
X-radiation; artificial membranes; crosslinking; electrolytes; fuel cells; functional properties; hydrogen; oxygen; permeability; polymers; propane; sorption; water vapor
Abstract:
... Original membranes based on an interpenetrating polymer network (IPN) architecture combining a poly(2-acrylamido-2-methyl-1-propane sulfonic acid) (AMPS) network and a fluorinated network were synthesized. The AMPS weight compositions were varied from 50 to 70wt%. The first network was achieved by radical copolymerization of AMPS with a fluorinated telechelic diacrylate while the second one was ob ...
DOI:
10.1016/j.memsci.2012.11.032

5. Bimetallic Co–Pd catalysts: Study of preparation methods and their influence on the selective hydrogenation of acetylene

Author:
Menezes, W.G.; Altmann, L.; Zielasek, V.; Thiel, K.; Bäumer, M.
Source:
Journal of catalysis 2013 v.300 pp. 125-135
ISSN:
0021-9517
Subject:
X-radiation; acetylene; atomic absorption spectrometry; carbon; catalysts; chemical composition; cobalt; energy; energy-dispersive X-ray analysis; hydrogen; hydrogenation; magnesium oxide; nanoparticles; polymers; polyols; pyrolysis; transmission electron microscopy
Abstract:
... Aiming at the preparation of catalysts with well-controlled structure and composition, bimetallic CoPd nanoparticles (NPs) were prepared in two different ways using polyol methods. In the first case, support materials, such as active carbon, MgO and γ-Al₂O₃, were present during synthesis, resulting in the formation of the particles directly on the surface of the supports. In the second case, funct ...
DOI:
10.1016/j.jcat.2012.12.023

6. Plasma Nanocoating of Thiophene onto TiO2 Nanoparticles

Author:
Oksuz, Aysegul Uygun; Manolache, Sorin; Oksuz, Lutfi; Hershkowitz, Noah
Source:
Industrial & Engineering Chemistry Research 2013 v.52 no.19 pp. 6610-6616
ISSN:
1520-5045
Subject:
Fourier transform infrared spectroscopy; X-radiation; coatings; engineering; ethylene; hydrogen; molecular weight; nanocomposites; nanoparticles; polymers; thermogravimetry; thiophene; titanium dioxide; transmission electron microscopy
Abstract:
... TiO₂ nanoparticles were coated uniformly, with a controllable thickness of conductive polymer polythiophene, in a rotating capacitively coupled radio-frequency (RF) plasma reactor. Plasma parameters such as power, pressure, and time affected the properties of the TiO₂/polythiophene nanocomposites, and plasma characteristics were examined using an optical monochromator, as well as in situ residual ...
DOI:
10.1021/ie303176j

7. Efficient photoinduced In situ preparation of clay/poly(glycidyl methacrylate) nanocomposites using hydrogen‐donor silane

Author:
Jlassi, Khouloud; Benna‐Zayani, Mémia; Chehimi, Mohamed M.; Yagci, Yusuf
Source:
Journal of polymer science 2015 v.53 no.6 pp. 800-808
ISSN:
0887-624X
Subject:
benzophenones; X-ray diffraction; nanocomposites; clay; transmission electron microscopy; hydrogen; polymers; bentonite; ethanol; X-radiation
Abstract:
... Clay/poly(glycidyl methacrylate) nanocomposites (clay/PGMA) were prepared by in situ radical photopolymerization using N,N‐dimethylaminopropyltrimethoxysilane(DMA)‐modified bentonite clay acting as hydrogen donor for benzophenone in solution. This initiating system permits to photopolymerize glycidyl methacrylate between the lamellae of the DMA‐modified clay. The approach provides exfoliated nanoc ...
DOI:
10.1002/pola.27505

8. Pd(II)-Directed Encapsulation of Hydrogenase within the Layer-by-Layer Multilayers of Carbon Nanotube Polyelectrolyte Used as a Heterogeneous Catalyst for Oxidation of Hydrogen

Author:
Liu, Jiang; Zorin, Nikolay A.; Chen, Meng; Qian, Dong-Jin
Source:
Langmuir 2015 v.31 no.23 pp. 6546-6553
ISSN:
1520-5827
Subject:
X-radiation; biocatalysis; biosensors; bromine; carbon nanotubes; catalysts; chemical bonding; color; diazonium compounds; encapsulation; fuel cells; gold; hydrogen; iron; methyl iodide; nanocomposites; nickel; oxidation; paraquat; polymers; quartz; transmission electron microscopes
Abstract:
... A metal-directed assembling approach has been developed to encapsulate hydrogenase (H₂ase) within a layer-by-layer (LBL) multilayer of carbon nanotube polyelectrolyte (MWNT-PVPMe), which showed efficient biocatalytic oxidation of H₂ gas. The MWNT-PVPMe was prepared via a diazonium process and addition reactions with poly(4-vinylpyridine) (PVP) and methyl iodide (MeI). The covalently attached polym ...
DOI:
10.1021/acs.langmuir.5b01376

9. Radiation-Grafted Polymer Electrolyte Membranes for Water Electrolysis Cells: Evaluation of Key Membrane Properties

Author:
Albert, Albert; Barnett, Alejandro O.; Thomassen, Magnus S.; Schmidt, Thomas J.; Gubler, Lorenz
Source:
ACS applied materials 2015 v.7 no.40 pp. 22203-22212
ISSN:
1944-8252
Subject:
X-radiation; electrodes; electrolysis; electrolytes; energy-dispersive X-ray analysis; ethylene; hydrogen; ion exchange; mechanical properties; polymers; scanning electron microscopy; spectroscopy; styrene; water uptake
Abstract:
... Radiation-grafted membranes can be considered an alternative to perfluorosulfonic acid (PFSA) membranes, such as Nafion, in a solid polymer electrolyte electrolyzer. Styrene, acrylonitrile, and 1,3-diisopropenylbenzene monomers are cografted into preirradiated 50 μm ethylene tetrafluoroethylene (ETFE) base film, followed by sulfonation to introduce proton exchange sites to the obtained grafted fil ...
DOI:
10.1021/acsami.5b04618

10. Preparation, characterization, and thermo-mechanical properties of poly (ε-caprolactone)-piperazine-based polyurethane-urea shape memory polymers

Author:
Eyvazzadeh Kalajahi, Alireza; Rezaei, Mostafa; Abbasi, Farhang
Source:
Journal of materials science 2016 v.51 no.9 pp. 4379-4389
ISSN:
0022-2461
Subject:
X-radiation; chemical composition; crystal structure; crystallization; crystals; differential scanning calorimetry; hydrogen; infrared spectroscopy; mechanical properties; melting point; nuclear magnetic resonance spectroscopy; piperazine; polymers; temperature; thermal properties; urea; urethane
Abstract:
... A series of segmented polyurethane-urea (PUU) shape memory polymers were synthesized from poly ε-caprolactone (PCL)-diol, hexamethylene diisocyanate, and piperazine (PP) with different hard to soft segment ratios. Chemical structure of PUUs was characterized using hydrogen nuclear magnetic resonance and attenuated total reflective-Fourier transform infrared spectroscopy methods. The results confir ...
DOI:
10.1007/s10853-016-9750-9

11. Stability and Degradation Mechanisms of Radiation-Grafted Polymer Electrolyte Membranes for Water Electrolysis

Author:
Albert, Albert; Lochner, Tim; Schmidt, Thomas J.; Gubler, L.
Source:
ACS Applied Materials & Interfaces 2016 v.8 no.24 pp. 15297-15306
ISSN:
1944-8252
Subject:
Fourier transform infrared spectroscopy; X-radiation; air; argon (noble gases); aspartate transaminase; electrolysis; electrolytes; energy-dispersive X-ray analysis; hydrogen; ion exchange; ion exchange chromatography; mechanical properties; oxygen; polymers; spectral analysis; styrene; temperature; thermal stress; ultraviolet-visible spectroscopy
Abstract:
... Radiation-grafted membranes are a promising alternative to commercial membranes for water electrolyzers, since they exhibit lower hydrogen crossover and area resistance, better mechanical properties, and are of potentially lower cost than perfluoroalkylsulfonic acid membranes, such as Nafion. Stability is an important factor in view of the expected lifetime of 40 000 h or more of an electrolyzer. ...
DOI:
10.1021/acsami.6b03050

12. Monodisperse Iridium Clusters Protected by Phenylacetylene: Implication for Size-Dependent Evolution of Binding Sites

Author:
Yamamoto, Hiroki; Maity, Prasenjit; Takahata, Ryo; Yamazoe, Seiji; Koyasu, Kiichirou; Kurashige, Wataru; Negishi, Yuichi; Tsukuda, Tatsuya
Source:
The Journal of Physical Chemistry C 2017 v.121 no.20 pp. 10936-10941
ISSN:
1932-7455
Subject:
Fourier transform infrared spectroscopy; X-radiation; X-ray absorption spectroscopy; X-ray photoelectron spectroscopy; absorption; alkynes; binding sites; chemical bonding; copper; ethylene; gold; hydrogen; iridium; ligands; mass spectrometry; models; nanoparticles; oxidation; polymers; silver; transmission electron microscopy
Abstract:
... Terminal alkynes form a variety of interfacial structures with the clusters and nanoparticles of Au, Ag, Cu, Ru, Pd, and Pt. In order to extend the scope of modification by alkynes, we herein report the synthesis and structure characterization of Ir clusters protected by phenylacetylene (PA). Small, monodisperse PA-protected Ir clusters (1.3 ± 0.2 nm) were obtained by biphasic ligand exchange from ...
DOI:
10.1021/acs.jpcc.6b12121

13. Plasma induced degradation and surface electronic structure modification of Poly(3-hexylthiophene) films

Author:
Tountas, Marinos; Georgiadou, Dimitra G.; Zeniou, Angelos; Seintis, Kostas; Soultati, Anastasia; Polydorou, Ermioni; Gardelis, Spyros; Douvas, Antonios M.; Speliotis, Thanassis; Tsikritzis, Dimitris; Kennou, Stella; Fakis, Mihalis; Gogolides, Evangelos; Tsoukalas, Dimitris; Argitis, Panagiotis; Vasilopoulou, Maria
Source:
Polymer degradation and stability 2018 v.149 pp. 162-172
ISSN:
0141-3910
Subject:
gases; X-ray photoelectron spectroscopy; energy; polymers; sulfonates; sulfur; thiophene; ultraviolet-visible spectroscopy; argon (noble gases); Fourier transform infrared spectroscopy; hydrogen; oxidation; photoluminescence; sulfonic acids; oxygen; X-radiation
Abstract:
... Plasma treatment is an environmentally friendly solution for modifying or nanostructuring the surface of several materials including photoactive polymers. The detailed characterization of the effect of plasma treatment on chemical and optoelectronic properties of photoactive polymers is, therefore, of specific interest. Herein, the effect of the exposure of poly(3-hexylthiophene) (P3HT) thin films ...
DOI:
10.1016/j.polymdegradstab.2017.12.010