Disk-like α-Fe2O3 microparticles were synthesized by a facile hydrothermal method and transformed into iron oxide/carbon composites by chemical vapor deposition in an acetylene atmosphere. Through careful control of the reaction time, carbon-coated porous γ-Fe2O3 microparticles with reversible Li+ storage properties were produced. The measured specific capacity after 40 cycles of charge and discharge was in excess of 900 mA h g−1 and rate capability was very good up to a current density of 2000 mA g−1. The good performance in Li+ storage could be attributed to the combination of porosity and a uniform nanocarbon coating which provided mixed-conducting properties for the fast diffusion of both lithium ions and electrons.

Synthesis of mixed-conducting carbon coated porous γ-Fe2O3 microparticles and their properties for reversible lithium ion storage

Polyvinyl alcohol (PVA) has been used to prevent flaking of paint pigments on traditional Japanese Shohekiga painted screens and panels. However, over time these PVA coatings whiten. To date, the mechanism of this whitening has not been studied from the point of view of polymer degradation. In this study, a piece of whitened PVA was obtained from a painted wooden panel. The PVA whitening mechanism was studied in this piece using scanning electron microscopy (SEM) and functional group analysis by Fourier transform-infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). SEM showed that the surface of the whitened PVA thin film was irregular and rugged, and many micrometer-sized cracks were observed. This suggests that efficient scattering of all visible light from the cracks causes whitening. FT-IR and XPS measurements revealed that inter- and intra-chain dehydration and chemical crosslinking (C–O ether linkage) occur on the surface of the whitened PVA. Polyvinyl alcohol (PVA), which has been used to prevent flaking of paint pigments on traditional Japanese Shohekiga, became white and we investigated its phenomenon. The surface of whitened PVA was irregular and rugged, and many micrometer size cracks were observed. This suggests that efficient scattering of all visible region light from the cracks causes whitening. Fourier transform-infrared spectroscopy and X-ray photoelectron spectroscopy measurements revealed that interchain dehydration and chemical crosslinking (C–O ether linkage) occurred on the surface of whitened PVA.

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Whitening of polyvinyl alcohol used as restoration material for Shohekiga

Characterization of amylose-g-poly(styrene) has been carried out employing ultraviolet, differentional thermal analysis, infrared, nuclear magnetic resonance and solubility techniques. It has been concluded that amylose-g-poly(styrene) is a true graft copolymer.

Characterization of Amylose‐g‐Poly (Styrene)

CHAPTER 4 – Block Copolymers and Polyblends

Complex formation between polymeric derivatives of ethinyl piperidol with potassium triiodide and 1-anilinonaphthalene-8-sulphonic acid was studied by IR, UV and fluorescence spectroscopic methods. Analysis of the spectra indicates that the piperidol ring acts as the centre of complex formation; the formed complex is stabilized by the hydrophobic segments of the polymer chain.

Complex formation of iodine and 1-anilinonaphthalene-8-sulphonic acid with polymeric derivatives of ethinyl piperidol

Infrared spectra of dehydrated polyvinyl alcohol

A study has been made of the homopolymerization of isopropenyl ethynyl trimethyl piperidole in bulk and in solution under the action of H2SO4, using a radical initiator. The polymer structure has been analyzed by IR and PMR spectroscopy methods, and the properties of dilute solutions of the polymer determined. Polymerization takes place by a radical mechanism, and the structure of the macromolecules is represented by a linear containing side piperidle rings that are interconnected by H bonds with participation of water of hydration molecules. The properties of a dilute solution of the iodomethylate of poly(isopropenyl) ethylnyl trimithyl piperidole) have been investigated, and the results interpreted in the light of concepts of the behaviour of polyelectrolytes.

Structural peculiarities and properties of poly(isopropenyl ethynyl trimethyl piperidole)

Infrared study of the structure of cellulose-polystyrene graft copolymer

By the methods of infrared and mass spectroscopy, the structure of grafted copolymer of polycaproamide (PCA) with polyacrylonitrile (PAN) was examined. It is shown on the grounds of analysis of infrared absorption bands and mass spectrum of the volatile products of grafted copolymer thermodestruction that the graft copolymerization in the redox system Fe+3/H2O2 is carried out at the expense of the radicals, formed on COOH groups of PCA. The structure of grafted chains PAN changes owing to formation of cycles containing S and CN groups at the grafted copolymer treatment with Na2S. By the means of complex thermal analysis, the steadiness of the obtained products to thermooxidizing destruction was investigated. It was found that the presence of sulfur in the grafted copolymer PCA–PAN considerably intensifies the processes of grafted-chain PAN cyclization as compared with the PAN homopolymer. It was shown that Na2S treatment brings to the product with the minimized absorption of oxygen at the isothermal heating that indicates its stability with regard to thermooxidizing destruction

Studies on the structure and resistance to thermooxidation of graft copolymer of polycaproamide with polyacrylonitrile and sulfur-containing derivatives

The spin label method was used to investigate molecular dynamics of cotton fibres. Mechanical strength parameters (Zhurkov equation) correlate with the relative content of “loose” structural defects in the fibre and with the rotary mobility of spin label in them.

R. Marupov

Papers

Infrared spectra of dehydrated polyvinyl alcohol

Structural peculiarities and properties of poly(isopropenyl ethynyl trimethyl piperidole)

Infrared study of the structure of cellulose-polystyrene graft copolymer

Studies on the structure and resistance to thermooxidation of graft copolymer of polycaproamide with polyacrylonitrile and sulfur-containing derivatives

Study of molecular dynamics of cotton fibres using the spin label method