scholarly journals Structure formation peculiarities of nickel-filled polyvinylpyrrolidone copolymers during polymerization with simultaneous Ni2+ reduction

2020 ◽  
Vol 3 (2) ◽  
pp. 127-134
Author(s):  
O. M. Grytsenko ◽  
◽  
O. V. Suberlyak ◽  
L. Dulebovа ◽  
I. Gaydos ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Polymer Matrix ◽  
Chemical Reduction ◽  
Structural Parameters ◽  
Reduction Process ◽  
Metal Particles ◽  
Polymerization Process ◽  
Nickel Ions ◽  
Monomer Composition ◽  
Matrix Volume

The course of the grafted polymerization of 2-hydroxyethylmethacrylate on polyvinylpyrrolidone with the formation of a reticulated copolymer with simultaneously chemical reduction of nickel ions is confirmed. The influence of the reduction process on the structural parameters of the polymeric matrix – the grafting efficiency and the content of polyvinylpyrrolidone in the copolymer, the molecular weight between crosslinks is established. The influence of the presence of polymer-monomer composition components on the particles formation of nickel filler is investigated. It has been found that the nickel ions reduction during the polymerization process promotes a uniform distribution of the formed metal particles in the polymer matrix volume.

scholarly journals Characterization of Ni-Cd Nanostructured System Obtained by Chemical Reduction of Salts

2016 ◽  
Vol 17 (4) ◽  
pp. 275 ◽  
Author(s):  
V.M. Pugachev ◽  
Yu.A. Zaharov ◽  
A.S. Valnyukova ◽  
V.G. Dodonov
Keyword(s):  
Chemical Reduction ◽  
Structural Parameters ◽  
Reduction Process ◽  
Metal Powders ◽  
X Ray Diffraction ◽  
X Ray ◽  
Initial Stage ◽  
Fcc Lattice ◽  
High Alkalinity

<p>The process of obtaining of highly dispersed metal powders of Ni-Cd system by reduction of their salts by hydrazine in aqueous medium at high alkalinity was investigated. The possibility of production metal powders containing up to 50 mol% of cadmium is established and conditions for their synthesis are optimized. Phase composition, structural parameters, dispersity of solid products during the reduction process were studied by X-ray diffraction (XRD) and SAXS. The formation of metal solid solutions with FCC lattice contradicts to the known phase diagram for Ni-Cd and may be explained by increasing the energy of the particles in the nanostate. The formation of intermetallide NiCd<sub>5</sub> in the studied compositions area is caused by sequential character of reduction process; as a result the metal product on the initial stage of reduction is significantly enriched with cadmium.</p>

Preparation and Characterization of Monodispersed and Nano-Sized Cu Powders

2007 ◽  
Vol 534-536 ◽  
pp. 109-112
Author(s):  
Tea Wan Kim ◽  
Hyang Mi Lee ◽  
Yong Yee Kim ◽  
Kyu Hong Hwang ◽  
Hong Chae Park ◽  
...  
Keyword(s):  
Particle Size ◽  
Polymer Matrix ◽  
Reaction Temperature ◽  
Chemical Reduction ◽  
Polymer Network ◽  
Reduction Process ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Nonionic Polymer ◽  
Copper Sulfate Pentahydrate

Monodispersed and nano-sized Cu powders were synthesized from copper sulfate pentahydrate (CuSO4ㆍ5H2O) inside a nonionic polymer matrix by using wet chemical reduction process. The sucrose was used as a nonionic polymer network source. The influences of a nonionic polymer matrix on the particle size of the prepared Cu powders were characterized by means of Xray diffraction (XRD), scanning electron microscopy (SEM), and particle size analysis (PSA). The smallen Cu powders with size of approximately 100㎚ was obtained with adding of 0.04M sucrose at reaction temperature of 60°C. The particle size of the Cu powders prepared by the reduction inside polymer network was strongly dependent of the sucrose content and reaction temperature.

scholarly journals Bimetallic Pd-Cu-composites of polyaniline in electrocatalytic hydrogenation of phenylacetylene

2017 ◽  
pp. 4-14
Author(s):  
Elena Soboleva ◽  
Yakha Visurkhanova ◽  
Nina Ivanova
Keyword(s):  
Catalytic Activity ◽  
Electrochemical Reduction ◽  
Polymer Matrix ◽  
Sodium Borohydride ◽  
Metal Content ◽  
Chemical Reduction ◽  
Metal Particles ◽  
Ethyl Benzene ◽  
Electrocatalytic Hydrogenation ◽  
Electro Catalytic Activity

Bimetallic Pd-Cu-composites of polyaniline prepared by introducing metals (II) chlorides in the process of oxida-tive polymerization of aniline with and without chemical reduction by sodium borohydride are applied to copper cath-ode activation in electrohydrogenation of phenylacetylene in basic aqueous ethanolic solutions of catholyte. Electro-catalytic activity of composites that they exhibited in the process is due to formation of metal particles (and their al-loys) by electrochemical reduction of metal cations in the polymer matrix. The main hydrogenation products are ethyl benzene and 1,4-diphenylbutane, the yields of which influence metal content in the studied composites.

ELECTROLESS NICKEL

Alloy Digest ◽  
1986 ◽  
Vol 35 (4) ◽  
Keyword(s):  
Nickel Coating ◽  
Chemical Reduction ◽  
Electroless Nickel ◽  
Heat Treating ◽  
Corrosion And Wear ◽  
Sodium Hypophosphite ◽  
Work Piece ◽  
Nickel Ions ◽  
Continuous Contact ◽  
Chemical Corporation

Abstract ELECTROLESS NICKEL is a nickel coating deposited by chemical reduction of nickel ions. The most widely used reducing agent is sodium hypophosphite. The thickness of the deposited coating is uniform over all areas of the work-piece that are in continuous contact with fresh plating solution. The process is applicable to a wide variety of metal and nonmetal substrates. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion and wear resistance as well as heat treating and joining. Filing Code: Ni-332. Producer or source: Occidental Chemical Corporation.

scholarly journals Facile Synthesis of Carboxymethyl Cellulose Coated Core/Shell SiO2@Cu Nanoparticles and Their Antifungal Activity against Phytophthora capsici

Polymers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 888
Author(s):  
Nguyen Thi Thanh Hai ◽  
Nguyen Duc Cuong ◽  
Nguyen Tran Quyen ◽  
Nguyen Quoc Hien ◽  
Tran Thi Dieu Hien ◽  
...  
Keyword(s):  
Antifungal Activity ◽  
Carboxymethyl Cellulose ◽  
Chemical Reduction ◽  
Low Cost ◽  
Phytophthora Capsici ◽  
Reduction Process ◽  
Spherical Shape ◽  
Core Shell ◽  
Cu Nanoparticles ◽  
Average Size

Cu nanoparticles are a potential material for creating novel alternative antimicrobial products due to their unique antibacterial/antifungal properties, stability, dispersion, low cost and abundance as well as being economical and ecofriendly. In this work, carboxymethyl cellulose coated core/shell SiO2@Cu nanoparticles (NPs) were synthesized by a simple and effective chemical reduction process. The initial SiO2 NPs, which were prepared from rice husk ash, were coated by a copper ultrathin film using hydrazine and carboxymethyl cellulose (CMC) as reducing agent and stable agent, respectively. The core/shell SiO2@Cu nanoparticles with an average size of ~19 nm were surrounded by CMC. The results indicated that the SiO2@Cu@CMC suspension was a homogenous morphology with a spherical shape, regular dispersion and good stability. Furthermore, the multicomponent SiO2@Cu@CMC NPs showed good antifungal activity against Phytophthora capsici (P. capsici). The novel Cu NPs-based multicomponent suspension is a key compound in the development of new fungicides for the control of the Phytophthora disease.

scholarly journals Size Control of Synthesized Silver Nanoparticles by Simultaneous Chemical Reduction and Laser Fragmentation in Origanum majorana Extract: Antibacterial Application

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2326
Author(s):  
Entesar Ali Ganash ◽  
Reem Mohammad Altuwirqi
Keyword(s):  
Silver Nanoparticles ◽  
Irradiation Time ◽  
Chemical Reduction ◽  
Size Control ◽  
Reduction Process ◽  
Laser Wavelength ◽  
X Ray Diffraction ◽  
Ag Nps ◽  
Transmission Electron ◽  
Origanum Majorana

In this work, silver nanoparticles (Ag NPs) were synthesized using a chemical reduction approach and a pulsed laser fragmentation in liquid (PLFL) technique, simultaneously. A laser wavelength of 532 nm was focused on the as produced Ag NPs, suspended in an Origanum majorana extract solution, with the aim of controlling their size. The effect of liquid medium concentration and irradiation time on the properties of the fabricated NPs was studied. While the X-ray diffraction (XRD) pattern confirmed the existence of Ag NPs, the UV–Vis spectrophotometry showed a significant absorption peak at about 420 nm, which is attributed to the characteristic surface plasmon resonance (SPR) peak of the obtained Ag NPs. By increasing the irradiation time and the Origanum majora extract concentration, the SPR peak shifted toward a shorter wavelength. This shift indicates a reduction in the NPs’ size. The effect of PLFL on size reduction was clearly revealed from the transmission electron microscopy images. The PLFL technique, depending on experimental parameters, reduced the size of the obtained Ag NPs to less than 10 nm. The mean zeta potential of the fabricated Ag NPs was found to be greater than −30 mV, signifying their stability. The Ag NPs were also found to effectively inhibit bacterial activity. The PLFL technique has proved to be a powerful method for controlling the size of NPs when it is simultaneously associated with a chemical reduction process.

Study on Structure and Tanning Properties of Copolymer of Resorcinol and 3,5-Dihydroxyl Benzoic Acid

2012 ◽  
Vol 487 ◽  
pp. 48-52
Author(s):  
Sheng Hua Lv ◽  
Gong Rui ◽  
Di Li
Keyword(s):  
Molecular Weight ◽  
Nuclear Magnetic Resonance ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Gel Permeation Chromatography ◽  
Radical Copolymerization ◽  
Mass Ratio ◽  
Monomer Composition ◽  
Chrome Tanning ◽  
Gel Permeation

The radical copolymerization of resorcinol (RSC) and 3,5-dihydroxyl benzoic (DHBA) was carried out in water by the initiator of horseradish (HRP)/H2O2. It was discussed that the effects of monomer composition on the properties of the copolymer. The best monomer mass ratio of RSC:DHBA was 60:40 and the shrink temperature can reached to 88.5oC. The tanning result indicated that the copolymer of RSC and DHPA has particularly excellent tanning properties and can be served as leather tannage substitute for chrome tanning materials. And also the mechanism of the HRP initiated copolymerization was proposed. The structure and molecular weight of the copolymer was characterized by Fourier Transform Infrared spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR) and Gel Permeation Chromatography (GPC). The copolymer can be as tannage and retannage in making leather process. The results showed that it has excellent tanning properties and retanning effects.

Hydrodynamic determination of molecular weight, dimensions, and structural parameters of Pf3 virus

Biochemistry ◽  
1982 ◽  
Vol 21 (14) ◽  
pp. 3352-3358 ◽  
Author(s):  
Jay Newman ◽  
Loren A. Day ◽  
Gregory W. Dalack ◽  
Don Eden
Keyword(s):  
Molecular Weight ◽  
Structural Parameters

Study of the effect of the reinforcement direction on the identification of relaxation transitions of moisture-saturated carbon fiber VKU-25

2021 ◽  
Vol 87 (9) ◽  
pp. 38-43
Author(s):  
O. G. Ospennikova ◽  
P. S. Marakhovsky ◽  
N. N. Vorobyov ◽  
E. V. Nikolaev ◽  
A. I. Gulyaev ◽  
...  
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Carbon Fiber ◽  
Polymer Matrix ◽  
Structural Parameters ◽  
Polymer Materials ◽  
Thermal Coefficient ◽  
Initial State ◽  
Relaxation Transitions

Thermodilatometric methods of analysis are used to study the structural parameters of polymer materials, however, when studying moisture-saturated compositions certain difficulties arise in their identification. The results of thermophysical tests of VKU-25 carbon fiber samples in the initial state and after moisture saturation are presented. It is shown that heat treatment of materials affects the recorded values of the glass transition temperature of the epoxy matrix. When the samples are exposed in water or above the water surface, the sorbate penetrates into the polymer at the same rate, which is confirmed by almost identical values of water absorption at the same exposure time. The estimates of the thermal coefficient of linear expansion (TCLE) of the samples in the range of 20 - 250°C are given. Moreover, it is shown that the glass transition temperature of the plasticized polymer matrix depends on the direction of fiber reinforcement. In the case of moisture-saturated carbon fiber (CF)heated to 210°C, the formation of main cracks occurs mainly at the fiber-matrix interface. The glass transition temperature (GTT) of the material in the dry state (176 - 177°C), appeared almost independent on the heating rate, whereas for water-saturated samples, GTT changes significantly and can be described by a polynomial of the 2nd order. After exposure of the carbon fiber under conditions of high temperature and humidity, two relaxation transitions corresponding to the systems occur in the polymer matrix: epoxidian oligomer— amine hardener and polyfunctional resin— amine hardener. The glass transition temperature is 132 and 159°C in the first and in the second, respectively. The results obtained can be used in the development of new polymer composite materials.

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