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Pomogailo, A. D.; Власенко, В. Г.; Shuvaev, A. T.; Rozenberg, A. S.; Джардималиева, Г. И.

doi:10.1023/a:1016824121525

Cited by 11 publications

(8 citation statements)

References 2 publications

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“…Thermal transformations go through three main macrostages with different temperatures [67][68][69][70][71][72][73][74][75]: (1) Initial monomer dehydration (desolvation) at 303-473 K; (2) the stage of solid-state homo-and copolymerization of the dehydrated monomer (at 473-573 K); (3) the produced polymer decarboxylation to a metal-containing phase and oxygen-free polymer matrix at T ex > 523 K with an intense gas emission. The analysis of the thermal transformation of the gaseous products and the composition of the solid product (decarboxylated polymer, including metal or its oxide) allows determining a general scheme of metal acrylate thermal transformations:…”

Section: Magnetic Metal Nanoparticles In Stabilizing the Polymer Matrmentioning

confidence: 99%

“…The thermal transformations of a series of unsaturated metal carboxylates [67][68][69][70][71][72][73][74][75] 6 · 3H 2 O maleates) and acrylamide complexes of metal nitrates (CoAAm, FeAAm) have been studied. Thermolysis of monomers under study is accompanied by the gas evolution and the mass loss due to the dehydration followed by thermal transformation of dehydrated specimens.…”

Section: The Kinetics Of Thermolysis Of Metal-containing Monomersmentioning

confidence: 99%

“…According to the data of TA [73][74][75][76][77][78]83], representative temperatures (T polym ) at which polymerization proceeds are as follows: ∼543 K (CoAcr 2 ), ∼563 K (NiAcr 2 ), ∼510 K (CuAcr 2 ), ∼518 K (FeAcr 3 ), 488-518 K (CoMal), ∼518 K (FeMal), 364 K (CoAAm). The EXAFS study of the solid-phase product at the initial stage of thermolysis (t term = 5 min at 643 K) also indicates the rearrangement of ligand environment of FeMal during its dehydration and polymerization [74,75]. As a result, Fe atoms coordinate O atoms of both carboxylate groups of maleate anion.…”

Section: Polymerizationmentioning

confidence: 99%

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Magnetic Metallopolymer Nanocomposites: Preparation and Properties

Джардималиева

Pomogailo

Rozenberg

et al. 2009

Magnetic Nanoparticles

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IntroductionThe various physical and mechanical parameters of metallopolymeric nanocomposites can be considerably improved with retention or sometimes even with the increase in the conventional magnetic characteristics (saturation magnetization, coercive force, etc.) that show considerable promise for various applications. Such substances are very perspective as high-density information media, materials for permanent magnets, magnetic cooling systems, or fabrication of magnetic sensors. They can also be used for medical and biological applications, e.g., for magnetic resonance tomography, magnetic targeted drug delivery systems, magnetic resonance imaging (MRI) contrast enhancement, color imaging, and cell sorting [1,2].Ferromagnetic metal particles can be formed in a polymer matrix (ferroplastics or ferroelastics) by practically all methods for synthesis of metal nanoparticles in polymers. The manufacturing method can be subdivided into three large groups: physical, chemical, and physicochemical. The division is very conventional and is based mostly on the method of nanoparticle formation and the character of their interactions with the matrix. The first group of methods includes the procedures seemingly devoid of any chemical interactions between the dispersed phase and the dispersion medium. Composites of this type are rare. More popular chemical methods of manufacturing nanocomposites are based on interactions between components anticipated or detected. The reduction reactions and precursors are well known. Nevertheless, the new approaches have been elaborated from practical demands and many details of the chemical reduction are still unclear. The third group of methods are those when metal or their oxide nanoparticles are formed using high-energy processes of atomic metal evaporation, including low-temperature discharge plasma, radiolysis, and photolysis in the presence of monomer and polymer. Recently, such methods have become widely used in vacuum metallization Magnetic Nanoparticles. Sergey P. Gubin

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Section: Magnetic Metal Nanoparticles In Stabilizing the Polymer Matrmentioning

confidence: 99%

Section: The Kinetics Of Thermolysis Of Metal-containing Monomersmentioning

confidence: 99%

Section: Polymerizationmentioning

confidence: 99%

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Magnetic Metallopolymer Nanocomposites: Preparation and Properties

Джардималиева

Pomogailo

Rozenberg

et al. 2009

Magnetic Nanoparticles

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“…The process temperature has a pronounced effect on the products' yield and their composition. Using EXAFS data [41,46], it was shown that even at the dehydration stage the metal ligand's surroundings become changed, and during the process such reconstruction is growing. At high temperatures the decarboxylation is accompanied by virtually complete removal of the oxygen-containing units from the polymer matrix.…”

Section: The Peculiarities Of Thermolysis Of Metal-containing Monomersmentioning

confidence: 99%

Controlled Pyrolysis of Metal‐Containing Precursors as a Way for Synthesis of Metallopolymer Nanocomposites

Pomogailo

Rozenberg

Джардималиева

2004

Metal–Polymer Nanocomposites

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The processes of thermal decomposition play an important role in various practical fields including metallurgy, mineral conversion processes, pyrogenic chemical technology, pyrolysis and thermal treatment of wood and coal, combustion of natural and synthetical fuels, coal carbonization, the prevention of grain spontaneous ignition, and so on. There is still a need for scientifically well-founded approaches to control the thermal decomposition of materials. Many studies focus attention on the chemical transformations and reactions in the pyrolized systems and on the creation of mathematical models of such processes as the major parts of the theory of chemical decomposition of complex substances.Thermolysis is widely used in the synthesis of nano-sized metallopolymer composites. This is a result of the specifics of the preparation of such materials. In spite of a variety of the methods for the preparation of metallopolymer nanocomposites, there are two principal routes: "bottom-up" and "top-down."

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“…The palladium content in the samples determined from the reflection intensity varies by an order of magnitude. The palladium dispersity calculated from the width of the reflection at 36o is 30 3 50 nm.Pomogailo [2] showed that transition metal nanoparticles are formed by reduction of their cations in an ion-exchange matrix. When the dynamic ion-exchange capacity is completely saturated with transition metal amine complexes, the reduced metal particles form the metallic phase owing to short effective distance between the particles [2].…”

mentioning

confidence: 99%

Preparation of ultradispersed transition metals in immobilized microreactors

Al'tshuler

Sapozhnikova

2004

Russ J Appl Chem

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Preparation of ultradispersed transition metals (20 !100 nm) by reduction of metal complexes in molecular microreactors (cavities of immobilized calixarenes, polyelectrolytes) was studied.Preparation and study of untradispersed metals and preparation of functional materials on their base are urgent problems of modern science [1]. It is known [2] that cross-linked polymers (polyelectrolytes) can be used as matrices for preparing ultradispersed metals. Cavities, complexes, and intercalated compounds contained in cross-linked polymers are immobilized microreactors providing certain spatial organization of molecules [3]. A study of processes occurring in immobilized microrecators gives insight into highly organized chemical transformations in supramolecular systems.Previously [4] we prepared new cross-linked polymers with grafted cis-calix[4]resorcinolarene derivatives capable of forming intercalation compounds [5], i.e., having properties of a microreactor.The aim of this work was to prepare ultradispersed transition metals in cross-linked polymers (polyelectrolytes), to study their catalytic activity in hydrogenation of organic nitro compounds, and to use cis-calix-[4]resorcinolarenes immobilized in the polymeric matrix as microreactors for reduction and hydrogenation. EXPERIMENTALUltradispersed metals (Pd, Cu, and Ni) were prepared in pores of KU-2-12P and KU-23 sulfonic cation exchangers, AV-17 anion exchanger, and cross-linked polymer with immobilized cis-tetraphenylcalix [4]resorcinolarene groups. The Cu 2+ , Ni 2+ , and [Pd(NH 3 ) 4 ] 2+ cations were introduced in the sulfonic cation exchanger by the ion-exchange procedure. Reduction of palladium(II) tetraammine complex in the matrix yields 20 3100-nm palladium particles. The X-ray pattern of KU-23 macroporous sulfonic cation exchanger containing palladium crystals is shown in Fig. 1.The X-ray patterns were recorded on a DRON-2 diffractometer (copper radiation, voltage on the X-ray tube 30 kV, current 20 mA, scan rate 2 deg min 31 ).The X-ray pattern contain reflections of crystalline palladium and a broad reflection of the amorphous polymer at 20o. The palladium content in the samples determined from the reflection intensity varies by an order of magnitude. The palladium dispersity calculated from the width of the reflection at 36o is 30 3 50 nm.Pomogailo [2] showed that transition metal nanoparticles are formed by reduction of their cations in an ion-exchange matrix. When the dynamic ion-exchange capacity is completely saturated with transition metal amine complexes, the reduced metal particles form the metallic phase owing to short effective distance between the particles [2]. The catalytic activity of these materials is low. For the ultradisperse phase to be formed, palladium cations should occupy less than 0.23 0.3 of the total exchange capacity of KU-23 sulfonic resin. The catalytic activity at the palladium 2G, deg Fig. 1 .X-ray pattern of KU-23 30/100 macroporous sulfonic cation exchanger containing (1) 5.1 and (2) 34 g md !3 palladium(II). (2q) Bragg ...

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Cited by 11 publications

References 2 publications

Magnetic Metallopolymer Nanocomposites: Preparation and Properties

Magnetic Metallopolymer Nanocomposites: Preparation and Properties

Controlled Pyrolysis of Metal‐Containing Precursors as a Way for Synthesis of Metallopolymer Nanocomposites

Preparation of ultradispersed transition metals in immobilized microreactors

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