Journal articles: 'Complexes polymère'

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Moulay, Saad. "Molecular iodine/polymer complexes." Journal of Polymer Engineering 33, no. 5 (August 1, 2013): 389–443. http://dx.doi.org/10.1515/polyeng-2012-0122.

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Abstract A unique feature of molecular iodine by far, is its ability to bind to polymeric materials. A plethora of natural and synthetic polymers develop complexes when treated with molecular iodine, or with a mixture of molecular iodine and potassium iodide. Many unexpected findings have been encountered upon complexation of iodine and the polymer skeleton, including the color formation, the polymer morphology changes, the complexation sites or regions, the biological activity, and the electrical conductivity enhancement of the complexes, with polyiodides (In¯), mainly I3¯ and I5¯, as the actual binding species. Natural polymers that afford such complexes with iodine species are starch (amylose and amylopectin), chitosan, glycogen, silk, wool, albumin, cellulose, xylan, and natural rubber; iodine-starch being the oldest iodine-natural polymer complex. By contrast, numerous synthetic polymers are prone to make complexes, including poly(vinyl alcohol) (PVA), poly(vinyl pyrrolidone) (PVP), nylons, poly(Schiff base)s, polyaniline, unsaturated polyhydrocarbons (carbon nanotubes, fullerenes C60/C70, polyacetylene; iodine-PVA being the oldest iodine-synthetic polymer complex.

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Bensacia, Nabila, Saâd Moulay, François Garin, Ioana Fechete, and Anne Boos. "Effect of Grafted Hydroquinone on the Acid-Base Properties of Poly(acrylic acid) in the Presence of Copper (II)." Journal of Chemistry 2015 (2015): 1–7. http://dx.doi.org/10.1155/2015/913987.

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Potentiometric titration of poly(acrylic acid) and hydroquinone-functionalized poly(acrylic acid) was conducted in the presence of copper (II). The effects of hydroquinone functionalizing and copper (II) complexing on the potentiometric titration of poly(acrylic acid) were studied in an ionic environment and in its absence. Henderson-Hasselbalch equation was applied to assess its validity for this titration. Coordination number and the stability constants of the copper- (II-)complexed polymers were determined, and results showed the formation of mostly monodentate and bidentate copper- (II-)polymer complexes.

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Bosch, Paula, Desislava Staneva, Evgenia Vasileva-Tonkova, Petar Grozdanov, Ivanka Nikolova, Rositsa Kukeva, Radostina Stoyanova, and Ivo Grabchev. "Hyperbranched Polymers Modified with Dansyl Units and Their Cu(II) Complexes. Bioactivity Studies." Materials 13, no. 20 (October 14, 2020): 4574. http://dx.doi.org/10.3390/ma13204574.

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Two new copper complexes of hyperbranched polymers modified with dansyl units were synthesized and characterized by infrared spectroscopy (IR) and electron paramagnetic resonance (EPR) techniques. It was found that copper ions coordinate predominantly with nitrogen or oxygen atoms of the polymer molecule. The place of the formation of complexes and the number of copper ions involved depend on the chemical structure of the polymer. The antimicrobial activity of the new polymers and their Cu(II) complexes was tested against Gram-negative and Gram-positive bacterial and fungal strains. Copper complexes were found to have activity better than that of the corresponding ligands. The deposition of the modified branched polymers onto cotton fabrics prevents the formation of bacterial biofilms, which indicates that the studied polymers can find application in antibacterial textiles.

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Kim, Ki-Seok, Sandipan Dutta, and YongSeok Jho. "Entangled polymer complexes as Higgs phenomena." Soft Matter 11, no. 40 (2015): 7932–41. http://dx.doi.org/10.1039/c5sm01763g.

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Entangled polymers are analogous to Higgs phenomena. The preserved linking number of the entangled polymer restricts the transverse motion of the test polymer, which corresponds to the microscopic picture of the tube model.

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Shtompel, V. I., V. L. Demchenko, V. O. Ovsyankina, A. V. Nischimenko, and S. V. Riabov. "Structure and properties of polyelectrolyte complexes of various type (chitosan chloride – polyacrilic acid) and triple polyelectrolyte-metalic complexe with cations Cu2+." Polymer journal 42, no. 4 (December 10, 2020): 277–82. http://dx.doi.org/10.15407/polymerj.42.04.277.

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Using FT-IR-spectroscopy, X-ray diffraction and thermomechanical analysis structure and thermomechanical properties of two nonstoichiometry and one stoichiometry polyelectrolyte complexes (PEC) based on opposite charged polyelectrolytes – strong cationic polyelectrolyte (chitosan chloride) and weak anionic polyelectrolyte (polyacrylic aсid) and triple polyelectrolyte-metal complexes (TPMC) based on stoichometry polyelectrolyte complexes and cations Cu(II) were investigated. It was shown, that chitosan chloride has amorphous-cristallinity structure, which is significantly different from the structure of neat chitosan, and polyacrylic acid posses amorphous structure. Meantime, all PEC samples have amorphous structure, differing from the structure of weak anionic polyelectrolyte, at the same time amorphous structure of nonstoichiometric PECs insignificantly different from that of stoichiometric polyelectrolyte complexes. Additionally, amorphous structure of TPMC has another structure, compared to all PEC. According to thermomechanical analysis, all PECs have one temperature transition from glassy to highly elastic state (from 77 to 84 °C). The deformation value of the samples of nonstoichiometric PEC is similar and somewhat less than the deformation of the stoichiometric PEC. The TPMC sample has two glass transitions (81 and 226 °C), and his high-temperature transition characterizes the segmental mobility of fragments of macromolecules of one stoichiometric PEC, the polar groups of which form chelate circles with Cu (II) cations. Deformation parameter of the TPMC is higher in comparison with the stoichiometric polyelectrolyte complexes. Keywords: structure, properties, deformation, ionic force, cationic Cu(II), polyelectrolyte, polyelectrolyte-metal complexes, chitosan chloride, polyacrylic acid, X-ray diffraction, thermomechanical analysis.

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Wang, Yu, Kenichi Oyaizu, and Hiroyuki Nishide. "Allylic hydrocarbon polymers complexed with Fe(II)(salen) as a ultrahigh oxygen-scavenging and active packaging film." Pure and Applied Chemistry 92, no. 6 (June 25, 2020): 871–82. http://dx.doi.org/10.1515/pac-2020-0102.

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AbstractMacromolecular metal complexes provide a molecular-based synergy function of organic polymers and combined metal complexes. A new category of macromolecular complexes includes catalytically active metal complexes immobilized by organic polymers containing reactive substrate moieties in their repeating units. Here, we describe the extremely efficient oxidation of allylic hydrocarbon polymers with the attached iron complex catalyst, as well as the efficient oxygen-consumption or oxygen-scavenging function of the matrix polymer film. The less toxic N,N´-di(salicylaldehyde)ethylenediiminatoiron(II) complex was combined with or fixed onto a series of allylic hydrocarbon polymers as both the oxidative substrate and the film matrix, i.e. poly(1,2-butadiene), polynorbornene, poly(5-vinyl-2-norbornene), poly(2,5-norboenadiene), poly(dicyclopentadiene), and poly(5-ethylidene-2-norbornene). Ultra-high oxygen-scavenging capacity up to 300 mL (oxygen gas at STP)/g(film) was achieved, based on the oxidative consumption of the allylic bond (particularly of poly(5-ethylidene-2-norbornene)), which was more than three times that of the previously reported highest oxygen-scavenging polymers. These oxygen-scavenging films are based on the high reactivity of polymer-metal complexes that provides an innovative development in the area of active packaging polymer films that facilitate cost-effective performance, safety, and sustainability.

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YAMASHITA, O., H. YOKOCHI, H. IMANISHI, and K. KANAYAMA. "PMC-01: Making a Complex Three-dimensional Shape from Bamboo(PMC-I: POLYMERS AND POLYMER MATRIX COMPOSITES)." Proceedings of the JSME Materials and Processing Conference (M&P) 2005 (2005): 1. http://dx.doi.org/10.1299/jsmeintmp.2005.1_3.

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Savitskaya, Tatsiana, Tatsiana Shybaila, and Yaheni Varanec. "POLYMER CHEMISTRY: INTERPOLYELECTROLYTE COMPLEXES ON THE BASE OF CHITIN AND CELLULOSE DERIVATIVES ARE SPECIAL CLASS OF POLYMER SUBSTANCES." GAMTAMOKSLINIS UGDYMAS / NATURAL SCIENCE EDUCATION 5, no. 3 (December 1, 2008): 50–57. http://dx.doi.org/10.48127/gu-nse/08.5.50b.

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The great importance of polymers in modern life has been shown. The paradoxicalness of the insufficient attention to polymer chemistry at school has been marked. The main difference between the composition and properties of low molecular compounds and polymer has been formulated. The results of the research of new polymers chemistry products – interpolyelectrolyte complexes of chitosan and cellulose water soluble derivative structure and properties have been presented. The use of interpolyelectrolyte complexes in the adsorption-flocculation water treatment process and as the enterosorbent veterinary preparation has been described. Keywords: polymers, chitosan, cellulose sulphate acetate.

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Hill, Christopher, Wasiu Abdullahi, Robert Dalgliesh, Martin Crossman, and Peter Charles Griffiths. "Charge Modification as a Mechanism for Tunable Properties in Polymer–Surfactant Complexes." Polymers 13, no. 16 (August 20, 2021): 2800. http://dx.doi.org/10.3390/polym13162800.

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Oppositely charged polymer–surfactant complexes are frequently explored as a function of phase space defined by the charge ratio Z, (where Z = [+polymer]/[−surfactant]), commonly accessed through the surfactant concentration. Tuning the phase behaviour and related properties of these complexes is an important tool for optimising commercial formulations; hence, understanding the relationship between Z and bulk properties is pertinent. Here, within a homologous series of cationic hydroxyethyl cellulose (cat-HEC) polymers with minor perturbations in the degree of side chain charge modification, phase space is instead explored through [+polymer] at fixed Cpolymer. The nanostructures were characterised by small-angle neutron scattering (SANS) in D2O solutions and in combination with the oppositely charged surfactant sodium dodecylsulfate (h- or d-SDS). Scattering consistent with thin rods with an average radius of ∼7.7 Å and length of ∼85 Å was observed for all cat-HEC polymers and no significant interactions were shown between the neutral HEC polymer and SDS (CSDS < CMC). For the charge-modified polymers, interactions with SDS were evident and the radius of the formed complexes grew up to ∼15 Å with increasing Z. This study demonstrates a novel approach in which the Z phase space of oppositely charged polymer–surfactant complexes can be controlled at fixed concentrations.

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10

Wei, Zhao, Yuehua Hu, Haisheng Han, Wei Sun, Ruolin Wang, Wenjuan Sun, Jianjun Wang, et al. "Selective Separation of Scheelite from Calcite by Self-Assembly of H2SiO3 Polymer Using Al3+ in Pb-BHA Flotation." Minerals 9, no. 1 (January 13, 2019): 43. http://dx.doi.org/10.3390/min9010043.

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The flotation separation of scheelite from calcite is problematic, where sodium silicate modified by polyvalent metal ions has shown some advantages for selective depression. In this study, an Al-Na2SiO3 polymer was used as the depressant for the flotation separation of scheelite from calcite using a lead complex of benzohydroxamic acid (Pb-BHA) as the collector. Furthermore, a number of measurements were conducted to investigate the structure of the Al-Na2SiO3 polymer and its adsorption behavior with Pb-BHA complexes on the mineral surface. Flotation experiments indicated that the Al-Na2SiO3 polymer shows good selectivity for the flotation separation of scheelite from calcite at pH 8, where the optimum ratio of sodium silicate to aluminum sulfate was 2:1. Fourier-Transform Infrared (FTIR) and solution chemical analyses revealed that aluminum hydroxide complexes and the hydroxy moiety of silicic acid are able to self-assemble via condensation affording an Al-Na2SiO3 polymer, i.e., a composite aluminosilicate polymer. The zeta potential measurements and adsorption capacity measurements indicated that, upon adsorption of the Al-Na2SiO3 polymer and Pb-BHA complexes on the mineral surface, the Al-Na2SiO3 polymer had less influence on the adsorption of Pb-BHA complexes on the scheelite surface, while the opposite was true for calcite. Therefore, more Pb-BHA complexes and fewer Al-Na2SiO3 polymers were deposited on the scheelite surface, while fewer Pb-BHA complexes and more Al-Na2SiO3 polymers were adsorbed on the calcite surface. The selective separation of scheelite from calcite was attributed to the cooperative selectivity of the Pb-BHA complexes and Al-Na2SiO3 polymer.

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11

Suleimenov, Ibragim, Dina Shaltykova, Grigoriy Mun, Polina Obukhova, Sergey Panchenko, and Nalik Isembergenov. "Influence of Hydrophilic Interpolymer Associates on the Formation of Interpolymer Complexes." Advanced Materials Research 749 (August 2013): 60–64. http://dx.doi.org/10.4028/www.scientific.net/amr.749.60.

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It is shown that when the conditions of formation of interpolymer complexes are met, another little-known product of the interaction of polymer - hydrophilic interpolymer associates are formed, representing structures, existing in the dynamic mode. Such associates occupy an intermediate position between the classical inter-polymer complexes and non-interacting polymers.

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12

Argaiz, Maialen, Fernando Ruipérez, Miren Aguirre, and Radmila Tomovska. "Ionic Inter-Particle Complexation Effect on the Performance of Waterborne Coatings." Polymers 13, no. 18 (September 14, 2021): 3098. http://dx.doi.org/10.3390/polym13183098.

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The performance of waterborne (meth)acrylic coatings is critically affected by the film formation process, in which the individual polymer particles must join to form a continuous film. Consequently, the waterborne polymers present lower performance than their solvent-borne counter-polymers. To decrease this effect, in this work, ionic complexation between oppositely charged polymer particles was introduced and its effect on the performance of waterborne polymer films was studied. The (meth)acrylic particles were charged by the addition of a small amount of ionic monomers, such as sodium styrene sulfonate and 2-(dimethylamino)ethyl methacrylate. Density functional theory calculations showed that the interaction between the selected main charges of the respective functional monomers (sulfonate–amine) is favored against the interactions with their counter ions (sulfonate–Na and amine–H). To induce ionic complexation, the oppositely charged latexes were blended, either based on the same number of charges or the same number of particles. The performance of the ionic complexed coatings was determined by means of tensile tests and water uptake measurements. The ionic complexed films were compared with reference films obtained at pH at which the cationic charges were in neutral form. The mechanical resistance was raised slightly by ionic bonding between particles, producing much more flexible films, whereas the water penetration within the polymeric films was considerably hindered. By exploring the process of polymer chains interdiffusion using Fluorescence Resonance Energy Transfer (FRET) analysis, it was found that the ionic complexation was established between the particles, which reduced significantly the interdiffusion process of polymer chains. The presented ionic complexes of sulfonate–amine functionalized particles open a promising approach for reinforcing waterborne coatings.

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13

Safiullina, Ilnara I., Elbeiy R. Babaev, Rauliya R. Syrlybaeva, and Nazrin Ch Movsum-zade. "NITRILE COMPLEXES AS EFFECTIVE ANTIMICROBIAL ADDITIVES." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 59, no. 5 (July 12, 2018): 81. http://dx.doi.org/10.6060/tcct.20165905.5341.

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Antimicrobial properties of nitrile complexes of transition metal salts were studied including the investigation of their activity in surfactants and mineral oil environments. Experiments of the polymeric complexes preparation by in-situ copolymerization of the nitrile polymers in the presence of transition metal salts and reactions of transition metal salts added to the ready polymers were performed. The dependence of the polymer complexes forming particularities on central metal atoms nature was determined.

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14

Moulay, Saad. "Macromolecule/Polymer-Iodine Complexes: An Update." Recent Innovations in Chemical Engineering (Formerly Recent Patents on Chemical Engineering) 12, no. 3 (October 21, 2019): 174–233. http://dx.doi.org/10.2174/2405520412666190716163611.

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The great chemical affinity of molecular iodine towards several macromolecules and innumerable polymers allows the formation of macromolecule/polymer-iodine complexes, usually commensurate with the desired uses and applications. In many instances, the formation of such complexes occurs through a charge-transfer mechanism. The strength of the ensued complex is more accentuated by the presence of heteroatoms (nitrogen, oxygen, sulfur) and the π-conjugation induced moieties within the chemical structure of the polymer. A wide range of polymers with high specific surface areas and large total pore volumes are excellent candidates for iodine adsorption, suggesting their use in the removal of radioactive iodine in nuclear power plants. The recent results of iodine uptake by polysaccharides such as starch, chitin, chitosan, alginate, and cellulose are but novelties. Complexing vinyl polymers such as poly(N-vinyl-2-pyrrolidone), poly(vinyl pyridine), poly(vinyl alcohol), poly(vinyl chloride), poly(acrylonitrile), and polyacrylics, with molecular iodine revealed special chemistry, giving rise to polyiodide ions (In -) as the actual complexing agents. Carbon allotropes (graphene, graphene oxide, carbon nanotubes, amorphous carbons) and polyhydrocarbons are prone to interact with molecular iodine. The treatment of a broad set of polymers and macromolecules with molecular iodine is but a doping process that ends up with useful materials of enhanced properties such conductivity (electrical, ionic, thermal); in some cases, the obtained materials were of engineering applications. Complexation and doping materials with iodine are also aimed at ensuring the antimicrobial activity, particularly, for those intended for medical uses. In several cases, the impact of the iodine doping of polymer is the alteration of its morphology, as is the case of the disruption of the graphitic morphology of the graphene or graphene oxide.

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Nishimura, Tomoki, Kaori Umezaki, Sada-atsu Mukai, Shin-ichi Sawada, and Kazunari Akiyoshi. "Amylose-Based Cationic Star Polymers for siRNA Delivery." BioMed Research International 2015 (2015): 1–6. http://dx.doi.org/10.1155/2015/962941.

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A new siRNA delivery system using a cationic glyco-star polymer is described. Spermine-modified 8-arm amylose star polymer (with a degree of polymerization of approximately 60 per arm) was synthesized by chemoenzymatic methods. The cationic star polymer effectively bound to siRNA and formed spherical complexes with an average hydrodynamic diameter of 230 nm. The cationic 8-arm star polymer complexes showed superior cellular uptake characteristics and higher gene silencing effects than a cationic 1-arm polymer. These results suggest that amylose-based star polymers are a promising nanoplatform for glycobiomaterials.

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Rodríguez, Rafael, Sandra Arias, Emilio Quiñoá, Ricardo Riguera, and Félix Freire. "The role of the secondary structure of helical poly(phenylacetylene)s in the formation of nanoparticles from polymer–metal complexes (HPMCs)." Nanoscale 9, no. 45 (2017): 17752–57. http://dx.doi.org/10.1039/c7nr04829g.

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17

Lee, Joon Y., Eric J. Moskala, Paul C. Painter, and Michael M. Coleman. "The Application of DRIFT Spectroscopy to Polymer Complexes." Applied Spectroscopy 40, no. 7 (September 1986): 991–94. http://dx.doi.org/10.1366/0003702864507918.

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Intermolecular interactions play a major role in the mixing of two polymers. In certain cases, where these interactions are particularly strong, polymer complexes with simple stoichiometrics may be formed. Many polymer mixtures of this type are insoluble and infusible, which complicates simple transmission infrared studies. In this note we present preliminary results on studies performed on polyvinyl phenol) mixtures with poly(2-vinyl pyridine) using diffuse reflectance and conventional transmission infrared spectroscopies together with thermal analysis. Diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy appears particularly useful in studies of these polymer complexes.

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18

Chardon-Noblat, Sylvie, Alain Deronzier, and Raymond Ziessel. "Electrosynthesis of Electroactive Metal-Metal Bonded Polymers [Ru(CO)2L]n (L = 2,2'-Bipyridine Derivatives), Their Characterization and Catalytic Activity. A Review." Collection of Czechoslovak Chemical Communications 66, no. 2 (2001): 207–27. http://dx.doi.org/10.1135/cccc20010207.

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This paper presents an account on the preparation, characterization and properties of conductive polymers [Ru(CO)2L]n (L = 2,2'-bipyridine derivatives). These strongly adherent and highly colored films containing Ru chains are unique examples of a new generation of organometallic polymers that possess interesting catalytic properties. The formation of these materials from mononuclear complexes like [RuCl2(CO)2L] and their properties were investigated by combined electrochemical techniques and UV-VIS, NMR, FTIR and EPR spectroscopies. The polymer is produced by electrochemically induced propagation involving the intermediate formation of dimers, tetramers and higher oligomers. The air sensitivity of this kind of Ru(0) polymers can be overcome by using polypyrrole matrix with L-attached mononuclear [RuCl2(CO)2L] precursor complexes. A following cathodic step leads, within the polypyrrole film, to the intended second polymer with Ru-Ru bonds. The morphology of this unusual hybrid polymer, investigated by scanning electron microscopy, revealed a uniform material. Regular films are formed by electrodeposition on carbon fibers. Most of these polymers possess high and selective catalytic activity in the electroreduction of carbon dioxide in aqueous media. A review with 36 references.

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Cherng, Jong Yuh. "Investigation of DNA Spectral Conformational Changes and Polymer Buffering Capacity in Relation to Transfection Efficiency of DNA/Polymer Complexes." Journal of Pharmacy & Pharmaceutical Sciences 12, no. 3 (November 26, 2009): 346. http://dx.doi.org/10.18433/j3859k.

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Purpose. The relation between transfection efficiency of DNA/polymer complexes and DNA conformational alterations is investigated. The buffering capacity of several synthetic polymers is also studied to relate their performance in transfection efficiency. Methods. The cationic polymer/DNA interaction was evaluated by measuring the alteration of DNA secondary structures in solution before and after the addition of polymer with ATR-FTIR technique. The degree of protonation in aqueous cationic polymers is varied upon pH and different structures. A polymer capable of protonation acts like a proton sponge to react with H+ in titration with HCl. This characteristic was evaluated in relation to transfection efficiency because the capacity would help the release of endocytotic DNA from endosome/lysosome on its way to expression. Results. IR results show that the antisymmetric PO2- vibration of DNA (at 1224 cm-1) shifts toward lower frequencies in complexation with PEI or PLLys (these polymers are able to transfect DNA). By contrast, the antisymmetric PO2- vibration of DNA in presence of PDAMA or dextran (these polymers are poor in DNA transfection) shows a shifting to higher frequencies or no alteration was observed. Interestingly, the polymers with best performance in transfection efficiency are in this order: PEI>PDMAEMA>PLLys>PDAMA>dextran which is in the same order as their polymer buffering capacity. These facts indicate polymers possessing better buffering capacity could result in higher transfection efficiency. Also, we have demonstrated in this paper that the antisymmetric PO2- stretching vibration in IR spectra is sensitive while binding of cationic polymers to DNA. These findings are useful for the development of polymer-based gene delivery systems with better performance in vitro and in vivo

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Matsuyama, Hiroyoshi, and J. Francis Young. "Synthesis of calcium silicate hydrate/polymer complexes: Part I. Anionic and nonionic polymers." Journal of Materials Research 14, no. 8 (August 1999): 3379–88. http://dx.doi.org/10.1557/jmr.1999.0458.

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High molecular weight anionic polymers have been incorporated into the calcium silicate hydrate (C–S–H) structure during precipitation of quasicrystalline C–S–H from aqueous solution. The anionic polymers studied were poly(methacrylic acid), poly(acrylic acid), and the sodium salt of poly(vinyl sulfonic acid). Expansion of the interlayer spacing coupled with high-carbon contents confirmed that the polymers intercalated between the layers. D-gluconic acid behaves similarly. Intercalation characteristics strongly depended on both the type of polymer and Ca/Si molar ratio of C–S–H; intercalation reached a maximum at an initial Ca/Si = 1.3 in all cases. Poly(vinyl alcohol) was the only nonionic polymer among those studied that was incorporated into C–S–H. Evidence for interlayer intercalation is less definite. The C–S–H/polymer complexes were examined by Fourier transform infrared spectroscopy, 29Si nuclear magnetic resonance magic angle spinning, and 13C cross-polarization, magic angle spinning nuclear magnetic resonance spectroscopy.

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Babayev, E. R., I. I. Safiullina, E. Kh Karimov, I. Z. Mukhametzyanov, A. Yu Bakhtina, and E. M. Movsumzade. "Acrylic polymers for conditions of weakly acid conversion to resins, complex syntheses." SOCAR Proceedings, no. 4 (December 31, 2020): 84–94. http://dx.doi.org/10.5510/ogp20200400469.

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The paper presents materials on the conversion of acrylic monomers to acrylic polymers. Similarly, polymers and copolymers obtained from acrylonitrile were prepared. On the basis of the results of quantum chemical calculations, the parameters of polymer and copolymer materials were established, which will make it possible to evaluate the possibilities of complexes of acrylonitrile polymers for the production of membranes.

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Gribkova, Oxana, Varvara Kabanova, Vladimir Tverskoy, and Alexander Nekrasov. "Comparison of Optical Ammonia-Sensing Properties of Conducting Polymer Complexes with Polysulfonic Acids." Chemosensors 9, no. 8 (August 4, 2021): 206. http://dx.doi.org/10.3390/chemosensors9080206.

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Thin films of conducting polymer complexes with polysulfonic acids of various structures were electrochemically deposited onto transparent FTO electrodes. The behavior of the polymer-based optical ammonia vapor sensors in response to various concentrations of ammonia vapors, ranging from 5 to 135 ppm, was investigated, including the response time and response amplitude. It was found that the nature of the conducting polymers (poly (3,4-ethylenedioxythiophene), polypyrrole, polyaniline), as well as the structure of the polyacids, affected the sensing performance of the obtained complexes.

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Zhang, Dingjun, Wenjin Zhao, Zhaoxuan Feng, Youzhi Wu, Caixia Huo, Ling He, and Wenjiang Lu. "Preparation of polymer–rare earth complexes based on Schiff-base-containing salicylic aldehyde groups attached to the polymer and their fluorescence emission properties." e-Polymers 19, no. 1 (May 8, 2019): 15–22. http://dx.doi.org/10.1515/epoly-2019-0003.

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AbstractIn this study, the salicylaldehyde hydrazone was bonded onto the side chains of poly (styrene-co-butyl acrylate), firstly obtaining a series of novel Schiff base-functionalized polymers. and using the base-containing polymers as macromolecular ligands through further reaction with EuCl3/YbCl3·6H2O, a series of polymer-rare earth complexes based on Eu(III)/Yb(III) ion were successfully prepared. The structures of the schiff base-containing polymers and their corresponding complexes were characterized by means of infrared spectra and UV spectra. The thermal properties of the functionalized polymers and complexes were investigated by TGA, and the fluorescence properties of the complexes were also researched by fluorescence spectrum. The experimental results show that the complexes have fine thermal stability likely because of the bidentate chelate effect of base-containing polymer and the conjugative effect of salicylaldehyde hydrazone group on the side chain of poly (styrene-co-butyl acrylate). More important, the salicylaldehyde hydrazone group on the side chains of poly(styrene-co-butyl acrylate) can efficaciously sensitize the fluorescence emission of the center ion due to effective intramolecular energy transfer. All the Eu(III)/Yb(III) complexes exhibit characteristic photoluminescence peaks in the visible region. The fluorescence excitation spectra of the complexes were obtained by monitoring the emission of Eu3+/Yb3+ ion at 497 nm, and the peak at 433 nm was found to be the optimal excitation peak. The concentration of salicylaldehyde hydrazone group was changed gradually with the variation of the molar ratio between the butyl acrylate and styrene (1:0.5; 1:1; 1:1.5; 1:2; 1:2.5), and the differences in their fluorescent intensity were followed, and the fluorescence intensity was very weak when the molar ratio of the butyl acrylate to styrene is equal to 1:2.5, while the fluorescence intensity reached a maximum value in the molar ratio of 1:1.

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Chen, Lu, and Yanbin Huang. "The guest polymer effect on the dissolution of drug–polymer crystalline inclusion complexes." RSC Advances 11, no. 22 (2021): 13091–96. http://dx.doi.org/10.1039/d1ra01926k.

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Götz, Stefan, Stefan Zechel, Martin D. Hager, and Ulrich S. Schubert. "Lanthanoids Goes Healing: Lanthanoidic Metallopolymers and Their Scratch Closure Behavior." Polymers 12, no. 4 (April 6, 2020): 838. http://dx.doi.org/10.3390/polym12040838.

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Metallopolymers represent an interesting combination of inorganic metal complexes and polymers resulting in a variety of outstanding properties and applications. One field of interest are stimuli-responsive materials and, in particular, self-healing polymers. These systems could be achieved by the incorporation of terpyridine–lanthanoid complexes of Eu (III), Tb (III), and Dy (III) in the side chains of well-defined copolymers, which were prepared applying the reversible addition fragmentation chain-transfer (RAFT)-polymerization technique. The metal complexes crosslink the polymer chains in order to form reversible supramolecular networks. These dynamics enable the self-healing behavior. The information on composition, reversibility, and stability of the complexes was obtained by isothermal titration calorimetry (ITC). Moreover, self-healing experiments were performed by using 3D-microscopy and indentation.

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Farah, Abdiaziz A., and William J. Pietro. "Telechelic poly(ε-caprolactones) with tethered mixed ligand ruthenium(II) chromophores." Canadian Journal of Chemistry 82, no. 5 (May 1, 2004): 595–607. http://dx.doi.org/10.1139/v03-215.

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Well-characterized templates of polymer-forming ligands and their ruthenium tris(α,α′-diimine) initiators were utilized to divergently ring open an ε-caprolactone monomer. The same polymers were also obtained through the synthesis of quinoline and bipyridine diimine ligands incorporating poly(ε-caprolactone) (PCL) chains. These polymers contain vacant molecular recognition sites, enabling subsequent chelation of these macroligands to metal precursors. Both methods provided telechelic (ε-caprolactone) ruthenium(II)-centered polyesters of various hierarchy. Solution properties and thermal behaviour of such polyesters are described.Key words: redox polymers, poly(ε-caprolactone), telechelics, metalpolymer complexes, macroligands, ring-opening polymerization (ROP).

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Grant, D., W. F. Long, and F. B. Williamson. "Infrared spectroscopy of heparin-cation complexes." Biochemical Journal 244, no. 1 (May 15, 1987): 143–49. http://dx.doi.org/10.1042/bj2440143.

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Hydrated and partially hydrated films and aqueous solutions of heparin, heparans and N-desulphated preparations of these polymers were studied by near- and fundamental-region-i.r. spectroscopy in the presence of a range of countercations. The results suggest that ion binding is not explicable solely in terms of simple electrostatic theory, and that specific cation effects, and the hydration pattern of the polymer-cation complex need to be taken into account.

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Iranmanesh, Hasti, Kasun S. A. Arachchige, William A. Donald, Niamh Kyriacou, Chao Shen, Jason R. Price, and Jonathon E. Beves. "Rage Against Conformity: Ruthenium(ɪɪ) Bisterpyridine Complexes Respond to Crystal Engineering Instructions with Whelming Results." Australian Journal of Chemistry 70, no. 5 (2017): 529. http://dx.doi.org/10.1071/ch16620.

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Four heteroleptic ruthenium(ii) complexes of 4′-functionalised 2,2′:6′,2′′-terpyridine are reported, along with their solid-state single-crystal X-ray structures. The complexes feature complementary hydrogen-bond donor (phenol) and acceptor (pyridyl) groups designed to assemble into one-dimensional polymers. In one example, the system obeys the programmed instructions to form a one-dimensional, self-complementary hydrogen-bonded polymer. In one other example, a water-bridged hydrogen-bonded polymer is formed. In the remaining two structures, aryl–aryl interactions dominate the intermolecular interactions, and outweigh the contribution of intermolecular hydrogen bonding.

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Ain, Shabnam, Babita Kumar, and Kamla Pathak. "DEVELOPMENT AND CHARACTERIZATION OF CONTROLLED RELEASE FAMOTIDINE MATRIX TABLETS CONTAINING COMPLEXES." International Journal of Applied Pharmaceutics 9, no. 4 (July 13, 2017): 38. http://dx.doi.org/10.22159/ijap.2017v9i4.18859.

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Objective: The aim of the present study was to formulate the controlled release (CR) tablets of famotidine-cyclodextrin complexes to make the feasibility of complex in CR tablets and to access the kinetic of drug release mechanismMethods: In this work the solubility study of famotidine was performed in various solvents like 0.1 N HCl, phosphate buffer pH 7.4 and distilled water. Enhancement of the solubility and dissolution rate of famotidine was done by complexation with cyclodextrin before formulation into controlled release tablets. Tablets were prepared in different batches by using different concentration of HPMC K15M (hydroxy propyl methyl cellulose) and EC (ethyl cellulose) polymers and polymer blend. All batches were evaluated for pre-compression and post-compression parameters. Release kinetics was analyzed using zero order, first order, higuchi, peppas and hixon-crowell model.Results: All the formulation showed compliance with Pharmacopoeial standards. Release studies indicated that polymer blend (62%HPMCK15M and 38%EC) based matrix tablets with complexed drug was able to control the release of famotidine up to 12 h. Optimized formulation F13 containing complexed drug with same polymer blend showed zero order release and the release mechanism was predominant matrix swelling with erosion.Conclusion: Results of the present study demonstrated that the drug: β-cyclodextrin complex would be a suitable candidate for preparing controlled release tablets of famotidine to improve drug solubility, flow properties and compressibility. Thus the complex used in matrix tablet is a promising approach to achieve appropriate controlled release dosage.

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Bazunova, Marina V., Robert A. Mustakimov, Nadezhda V. Dmitrieva, Diana R. Dayanova, and Andrey A. Bazunov. "Study of the physical and chemical properties of materials based on polymer complexes of some water-soluble polymers." Butlerov Communications 62, no. 5 (May 31, 2020): 91–96. http://dx.doi.org/10.37952/roi-jbc-01/20-62-5-91.

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Polymer complexes based on water-soluble physiologically-neutral polymers are promising for creating biomedical materials used in targeted delivery systems of drugs, enzymes or genes, as well as for encapsulating biological substances in biomedicine. In this work, the creation of film materials based on polymer complexes has used the sodium salt of succinyl chitosan, polyvinylpyrrolidone, sodium salt of carboxymethylcellulose, polyethylene glycol. Polyvinylpyrrolidone and polyethylene glycol are characterized by unsatisfactory a film-forming and gel-forming property, which limits their application in medical practice. These shortcomings have been compensated by the introduction of polysaccharides. It has been shown that the variation in composition of the studied polymer complexes allows changing purposefully the hydrophilic-hydrophobic balance of the surface and sorption properties of polymer films based on them. The preparation of polymer complexes consisted of adding a portion of poly-N-vinylpyrrolidone or polyethylene glycol to solutions of the sodium salt of succinyl chitosan or sodium salt of carboxymethylcellulose so that the ratio of the components of the complex was equimolar. Films based on polymer complexes were prepared by the method of pouring solutions of polymer mixtures with a concentration of 1 mol/L onto a previously defatted surface of a Petri dish. The thickness of the film samples was maintained constant and equal to 0.1 mm. It was shown that the preparation of polymer complexes of the sodium salt of chitosan succinyl or the sodium salt of carboxymethyl cellulose with poly-(N-vinylpyrrolidone) or polyethylene glycol allows one to purposefully change the hydrophilic-hydrophobic balance of the surface of polymer films based on them. Also, film materials based on the studied polymer complexes have satisfactory sorption properties for water vapor. These facts suggest that systems based on polymer complexes of the sodium salt of chitosan succinyl or sodium salt of carboxymethylcellulose with poly (N-vinyl pyrrolidone) or polyethylene glycol can serve as the basis for the creation of film or gel polymer materials for medical use.

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Dmitrieva, T. V., S. M. Kobylinsky, V. V. Boyko, S. V. Riabov, V. I. Bortnitskiy, S. K. Krymovska, G. F. Nevmerzhitska, and O. M. Komljakova. "The influence of pectin based metal-complexes on degradation of polyethylene." Polymer journal 37, no. 3 (September 20, 2015): 263–68. http://dx.doi.org/10.15407/polymerj.37.03.263.

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Artykulnyi, O. P., V. I. Petrenko, M. V. Avdeev, and L. A. Bulavin. "Complexes of Surfactant Micelles with Polymers in Aqueous Liquid Systems." Ukrainian Journal of Physics 65, no. 9 (August 26, 2020): 784. http://dx.doi.org/10.15407/ujpe65.9.784.

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Researches on the structural self-organization and aggregation in aqueous liquid systems of surfactants and polymers have been reviewed. Main attention is focused on the results obtained for the interaction of ionic surfactants with non-ionic polymers. Capabilities of the small-angle neutron scattering and neutron reflectometry methods for the study of the micellar structure, micelle-polymer aggregates, and complex multicomponent systems with nanoparticles are considered. Brief information is provided on some complementary methods used for the structural analysis of liquid systems with self-organization.

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Ratner, Mark A., and D. F. Shriver. "Polymer Ionics." MRS Bulletin 14, no. 9 (September 1989): 39–51. http://dx.doi.org/10.1557/s0883769400061728.

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The preparation, utilization, and understanding of high polymers represents one of the great triumphs of chemistry and materials science in the 20th century. Synthetic polymers have traditionally been used as structural materials and electrical insulators. Biopolymers often exhibit interesting electrical response phenomena. A recent article in the MRS BULLETIN, for example, discussed piezoelectric properties of both synthetic and biopolymer systems. The newer, synthetic electroactive polymeric materials, however, represent one of the most exciting current areas of polymer materials science.Many synthetic ionic polymer materials are known; perhaps the first were the polyelectrolytes and crosslinked ion exchange materials. These are materials whose backbone contains charges of one sign, balanced by small counter ions of the opposite sign. Such polyelectrolytes have found very important applications in analytical chemistry, water purification, and chemical processing.Complexes, in which salts are dissolved in neutral polymer hosts, have until recently received less attention. The area of polymer/salt complexes became extremely active following the work of P.V. Wright, who first clearly showed that polyethylene oxide (PEO) is an excellent polymer host for a number of salts, and that the resulting solid polymer/salt complexes are electrical conductors. M. Armand broadened the investigation of electrical properties of polymer/salt complexes and pointed out that these materials might be useful in electrochemical devices, especially batteries.This article will discuss the formation, properties, behavior, and applications of polymer electrolytes and mixed conductors—that is, polymeric materials in which charge is transported either by ions or by ionic and electronic charge motion. Our concentration will be on solvent-free materials—materials in which no small molecule solvents are present. There is substantial interest, and substantial progress, in the area of solvent-swollen polymer electrolytes.

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Каплин, В. С., А. С. Копылов, Т. С. Зархина, П. С. Тимашев, and А. Б. Соловьева. "Люминесцентные свойства разнолигандных beta-дикетонатов неодима, полученных в среде сверхкритического диоксида углерода в полимерных матрицах различной природы." Журнал технической физики 129, no. 7 (2020): 869. http://dx.doi.org/10.21883/os.2020.07.49555.30-20.

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Multi-ligand phosphor complexes of neodymium acetylacetonate with phenanthroline are synthesized in polymer matrices (oligourethane methacrylate, fluoroplast, polycarbonate) in supercritical carbon dioxide medium. At the same time the role of one of the ligands in such complexes is played by fragments of the polymer matrix. The luminescence spectra of the obtained ternary systems are described. It was shown that the position of the luminescence maxima is bathochromically shifted relative to the binary systems Nd(Acac)3/polymer obtained in a similar way and the magnitude of the shift depends on the nature of the polymer matrix. It was shown that upon the introduction of these components into polymers from a solution, similar phosphor mixed-ligand neodymium complexes do not form. The formation of new structures Nd(Acac)3/Phen/polymer upon impregnation of oligourethane methacrylate with neodymium β-diketonate and phenanthroline in a supercritical CO2 medium was confirmed by the method of differential thermal analysis. The same method confirmed that with the introduction of these components from the solution of the above systems do not form.

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Bago Rodriguez, Ana Maria, Bernard P. Binks, and Tomoko Sekine. "Novel stabilisation of emulsions by soft particles: polyelectrolyte complexes." Faraday Discussions 191 (2016): 255–85. http://dx.doi.org/10.1039/c6fd00011h.

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We put forward the concept of a novel particle stabiliser of oil–water emulsions, being the polyelectrolyte complex (PEC) formed between oppositely charged water-soluble polymers in cases where either polymer alone is incapable of stabilising an emulsion. Using poly(4-styrene sulfonate) sodium salt, PSSNa and poly(diallyldimethylammonium chloride), PDADMAC, of low polydispersity and similar molecular mass, we correlate the behaviour of their mixtures in water with that of emulsions after addition of oil. In aqueous mixtures, spherical particles of diameters between 100 and 150 nm are formed through electrostatic interactions between charged polymer chains. Around equal mole fractions of the two polymers, the zeta potential of the particles reverses in sign and emulsions of oil-in-water (o/w) for a range of oils can be prepared which are the most stable to coalescence and creaming. The effects of PEC concentration and the oil : water ratio have been examined. All emulsions are o/w and stability is achieved by close-packed particle layers at drop interfaces and particle aggregation in the continuous phase. Increasing the salt concentration initially causes destabilisation of the aqueous particle dispersion due to particle aggregation followed by dissolution of particles at high concentrations; the corresponding emulsions change from being stable to completely unstable and are then re-stabilised due to adsorption of uncharged individual polymer molecules.

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Jiang, Qian, Nicolas Desbois, Shifa Wang, and Claude P. Gros. "Recent developments in dipyrrin based metal complexes: Self-assembled nanoarchitectures and materials applications." Journal of Porphyrins and Phthalocyanines 24, no. 05n07 (May 2020): 646–61. http://dx.doi.org/10.1142/s1088424620300025.

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While dipyrrin-boron complexes (BODIPYs) and their derivatives have attracted much attention, dipyrrin-based metal complexes recently appeared as a novel luminescent material. So far, dipyrrin-metal complexes have been regarded as non-luminescent or weakly luminescent. Interestingly, introduction of steric hindrance at the meso-position and the development of heteroleptic complexes with proper frontier orbital ordering are two recent strategies that have been developed to improve their luminescent ability. Compared with BODIPYs, one of the distinctive advantages of dipyrrin-metal complexes is that they can form a series of self-assembled supramolecules and polymer assemblies via facile coordination reactions. In recent times, several supramolecular, coordination polymers and Metal-Organic Frameworks (MOFs) have been developed, [Formula: see text] by spontaneous coordination reactions between dipyrrin ligands and metal ions. As a novel luminescent material, dipyrrin-metal complexes have been applied in many fields. This review article summarizes recent developments in dipyrrin-metal complexes from the viewpoint of the improvement of luminescent ability, the formation of supramolecular and coordination polymers and their potential applications.

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Fuller, Carl W., Shiv Kumar, Mintu Porel, Minchen Chien, Arek Bibillo, P. Benjamin Stranges, Michael Dorwart, et al. "Real-time single-molecule electronic DNA sequencing by synthesis using polymer-tagged nucleotides on a nanopore array." Proceedings of the National Academy of Sciences 113, no. 19 (April 18, 2016): 5233–38. http://dx.doi.org/10.1073/pnas.1601782113.

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DNA sequencing by synthesis (SBS) offers a robust platform to decipher nucleic acid sequences. Recently, we reported a single-molecule nanopore-based SBS strategy that accurately distinguishes four bases by electronically detecting and differentiating four different polymer tags attached to the 5′-phosphate of the nucleotides during their incorporation into a growing DNA strand catalyzed by DNA polymerase. Further developing this approach, we report here the use of nucleotides tagged at the terminal phosphate with oligonucleotide-based polymers to perform nanopore SBS on an α-hemolysin nanopore array platform. We designed and synthesized several polymer-tagged nucleotides using tags that produce different electrical current blockade levels and verified they are active substrates for DNA polymerase. A highly processive DNA polymerase was conjugated to the nanopore, and the conjugates were complexed with primer/template DNA and inserted into lipid bilayers over individually addressable electrodes of the nanopore chip. When an incoming complementary-tagged nucleotide forms a tight ternary complex with the primer/template and polymerase, the tag enters the pore, and the current blockade level is measured. The levels displayed by the four nucleotides tagged with four different polymers captured in the nanopore in such ternary complexes were clearly distinguishable and sequence-specific, enabling continuous sequence determination during the polymerase reaction. Thus, real-time single-molecule electronic DNA sequencing data with single-base resolution were obtained. The use of these polymer-tagged nucleotides, combined with polymerase tethering to nanopores and multiplexed nanopore sensors, should lead to new high-throughput sequencing methods.

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38

Lv, Wei, Huijiao Liu, Wen Wang, E. Yang, Hongyu Zhen, and Qidan Ling. "Synthesis of new conjugated polymers with coordinated praseodymium complexes for polymer memory devices." RSC Advances 7, no. 30 (2017): 18384–91. http://dx.doi.org/10.1039/c6ra28757c.

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A series of novel praseodymium(Pr)-coordinated polymers with phthalimide moieties were synthesized. The effects of the phthalimide moiety and neutral Pr complex on the polymer memory device performance were investigated.

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39

Chen, Jihua. "Advanced Electron Microscopy of Nanophased Synthetic Polymers and Soft Complexes for Energy and Medicine Applications." Nanomaterials 11, no. 9 (September 15, 2021): 2405. http://dx.doi.org/10.3390/nano11092405.

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After decades of developments, electron microscopy has become a powerful and irreplaceable tool in understanding the ionic, electrical, mechanical, chemical, and other functional performances of next-generation polymers and soft complexes. The recent progress in electron microscopy of nanostructured polymers and soft assemblies is important for applications in many different fields, including, but not limited to, mesoporous and nanoporous materials, absorbents, membranes, solid electrolytes, battery electrodes, ion- and electron-transporting materials, organic semiconductors, soft robotics, optoelectronic devices, biomass, soft magnetic materials, and pharmaceutical drug design. For synthetic polymers and soft complexes, there are four main characteristics that differentiate them from their inorganic or biomacromolecular counterparts in electron microscopy studies: (1) lower contrast, (2) abundance of light elements, (3) polydispersity or nanomorphological variations, and (4) large changes induced by electron beams. Since 2011, the Center for Nanophase Materials Sciences (CNMS) at Oak Ridge National Laboratory has been working with numerous facility users on nanostructured polymer composites, block copolymers, polymer brushes, conjugated molecules, organic–inorganic hybrid nanomaterials, organic–inorganic interfaces, organic crystals, and other soft complexes. This review crystalizes some of the essential challenges, successes, failures, and techniques during the process in the past ten years. It also presents some outlooks and future expectations on the basis of these works at the intersection of electron microscopy, soft matter, and artificial intelligence. Machine learning is expected to automate and facilitate image processing and information extraction of polymer and soft hybrid nanostructures in aspects such as dose-controlled imaging and structure analysis.

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40

Fleischmann, Carolin, Hendrik Wöhlk, and Helmut Ritter. "End group functionalization of poly(ethylene glycol) with phenolphthalein: towards star-shaped polymers based on supramolecular interactions." Beilstein Journal of Organic Chemistry 10 (September 25, 2014): 2263–69. http://dx.doi.org/10.3762/bjoc.10.235.

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The synthesis of a new phenolphthalein azide derivative, which can be easily utilized in polymer analogous reactions, is presented. The subsequent cycloaddition reaction with propargyl-functionalized methoxypoly(ethylene glycol) yielded polymers bearing phenolphthalein as the covalently attached end group. In presence of per-β-cyclodextrin-dipentaerythritol, the formation of stable inclusion complexes was observed, representing an interesting approach towards the formation of star shaped polymers. The decolorization of a basic polymer solution caused by the complexation was of great advantage since this behavior enabled following the complex formation by UV–vis spectroscopy and even the naked eye.

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41

Saha, Debasish, Karthik R. Peddireddy, Jürgen Allgaier, Wei Zhang, Simona Maccarrone, Henrich Frielinghaus, and Dieter Richter. "Amphiphilic Comb Polymers as New Additives in Bicontinuous Microemulsions." Nanomaterials 10, no. 12 (December 2, 2020): 2410. http://dx.doi.org/10.3390/nano10122410.

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It has been shown that the thermodynamics of bicontinuous microemulsions can be tailored via the addition of various different amphiphilic polymers. In this manuscript, we now focus on comb-type polymers consisting of hydrophobic backbones and hydrophilic side chains. The distinct philicity of the backbone and side chains leads to a well-defined segregation into the oil and water domains respectively, as confirmed by contrast variation small-angle neutron scattering experiments. This polymer–microemulsion structure leads to well-described conformational entropies of the polymer fragments (backbone and side chains) that exert pressure on the membrane, which influences the thermodynamics of the overall microemulsion. In the context of the different polymer architectures that have been studied by our group with regards to their phase diagrams and small-angle neutron scattering, the microemulsion thermodynamics of comb polymers can be described in terms of a superposition of the backbone and side chain fragments. The denser or longer the side chain, the stronger the grafting and the more visible the brush effect of the side chains becomes. Possible applications of the comb polymers as switchable additives are discussed. Finally, a balanced philicity of polymers also motivates transmembrane migration in biological systems of the polymers themselves or of polymer–DNA complexes.

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Kobylinskiy, S. M., T. V. Dmytrieva, S. K. Krymovska, V. I. Bortnytsky, and S. V. Riabov. "The influence of chitosan-polylactic acid metal complexes on the degradation of polyethylene." Polymer journal 37, no. 4 (December 20, 2015): 375–80. http://dx.doi.org/10.15407/polymerj.37.04.375.

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Demchenko, V. L. "Polyelectrolyte complexes based on pectin, and poly(4-vinylpyridine): structure and thermomechanical properties." Polymer journal 38, no. 1 (March 20, 2016): 34–39. http://dx.doi.org/10.15407/polymerj.38.01.034.

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Demchenko, V. L., V. I. Shtompel’, and L. A. Goncharenko. "The structure and thermomechanical properties of polyelectrolyte complexes based on carboxymethylcellulose and polyethyleneimine." Polymer journal 39, no. 1 (March 5, 2017): 39–43. http://dx.doi.org/10.15407/polymerj.39.01.39.

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45

Kulik, T. V., T. V. Podust, and B. B. Palianytsia. "Supramolecular complexes of iodine-chitosan in solution and on the surface of silica." Polymer journal 39, no. 4 (December 20, 2017): 241–47. http://dx.doi.org/10.15407/polymerj.39.04.241.

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46

Velada, José L., Luis C. Cesteros, and I. Katime. "Infrared Study of the Interactions between Poly(Vinyl Pyridines) and Poly(Mono-n-Alkyl Itaconates)." Applied Spectroscopy 50, no. 7 (July 1996): 893–99. http://dx.doi.org/10.1366/0003702963905529.

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In this paper we have performed a spectroscopic study of the polymer–polymer complexes and polymer blends formed by mixing poly-acids [a series of poly(mono- n-alkyl itaconates)], and polybases [poly(2-vinyl pyridine) and poly(4-vinyl pyridine)]. The poly(mono- n-alkyl itaconates) are proton donors and the poly(vinyl pyridines) are good proton-acceptor polymers. Therefore, these pairs of polymers can interact via hydrogen bonding under given conditions. The obtained spectroscopic results point out the existence of hydrogen bonding in the studied systems. In addition to the qualitative hydrogen-bonding evidence observed in the hydroxyl and carbonyl stretching region, the curve-fitting analysis of the characteristic modes of the pyridine groups allows a quantitative study of the specific interactions to be performed.

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Uznanski, P., J. Pecherz, and M. Kryszewski. "Photophysical studies of hydrophobically functionalized polyionene systems in aqueous solutions." Canadian Journal of Chemistry 73, no. 11 (November 1, 1995): 2041–46. http://dx.doi.org/10.1139/v95-252.

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Complexes of polyionene and anionic dyes and surfactant were prepared by exchange reaction of counterions in the parent polymer. Fluorescence studies were conducted to observe some characteristic behaviour of these complexes in water Polyionenes with aromatic hydrocarbons adopt an open conformation and there is no evidence for interpolymer interactions. On the contrary, polyionenes with long aliphatic counterions easily form microdomains in aqueous solution due to hydrophobic interaction as evidenced by an increase in excimer emission. Microdomains have an interpolymer nature, as confirmed by measurements of energy transfer from naphthalene to pyrene moieties. Polyionenes with SDS counterions interact with external surfactant molecules and form polymer–surfactant aggregates. Electrostatic repulsions between aggregates dominate on hydrophobic interaction between polymer chains and are responsible for conformational changes. Keywords: hydrophobically modified polymers, surfactants, complexation, fluorescence, nonradiative energy transfer

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48

Demchenko, V. L., V. I. Shtompel, S. V. Riabov, and T. A. Polischuk. "Structural organization, thermomechanical and electrical properties of polyelectrolyte complexes based on pectin and polyethyleneimine." Polymer journal 37, no. 4 (December 20, 2015): 347–53. http://dx.doi.org/10.15407/polymerj.37.04.347.

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MATHEW, TESSYMOL, and SUNNY KURIAKOSE. "Cobalt(II) Porphyrins Supported on Crosslinked Polymer Matrix as Model Compounds." Journal of Porphyrins and Phthalocyanines 03, no. 04 (April 1999): 316–21. http://dx.doi.org/10.1002/(sici)1099-1409(199904)3:4<316::aid-jpp136>3.0.co;2-z.

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Polymer-bound cobalt(II) porphyrins were studied for their dioxygen—binding capacity. Tetra—aminoporphyrins were anchored on a divinylbenzene (DVB)-crosslinked chloromethyl polystyrene network. The crosslinked, solid polymers were swelled in chloroform and the swollen polymers were used for the entire studies. Ortho-, meta- and para-substituted porphyrin systems were developed by adjusting the bonding position with the help of suitably substituted aminoporphyrins. The products were characterized by chemical and spectroscopic methods. Cobalt(II) complexes of polymeric porphyrins were synthesized and characterized by electronic and ESR spectral methods. The spectra gave evidence for the systematic variation of electronic properties in ortho, meta and para compounds and for the dioxygen-binding capacity of cobalt complexes. These results are discussed.

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Rajan, Siji, F. Richard Keene, and Peter J. Steel. "Metallosupramolecular Chemistry of AgI Complexes with Azobis(2-pyridine) and its Derivatives." Australian Journal of Chemistry 69, no. 6 (2016): 612. http://dx.doi.org/10.1071/ch15560.

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Reactions of three azobis(2-pyridines) with silver salts lead to 1D coordination polymers whose structures have been determined by single crystal X-ray crystallography. The azobis(2-pyridines) consistently act as di-bidentate ligands that bridge silver atoms separated by distances ranging from 5.49 to 5.82 Å. Two of the coordination polymers consist of chains in which consecutive bridging ligands are orthogonally oriented. The other polymer has a considerably more complicated structure due to the more intimate involvement of the trifluoroacetate counteranions, which also act as bridges between silver centres.

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Journal articles on the topic 'Complexes polymère'

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