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Two methods for the functionalization of single-walled nanotubes were proposed, namely grafting of acyllactam groups or amine-terminated polyimides. Such modification allows for the preparation of stable nonsagging nanotubes dispersions in the melted e-caprolactam. These dispersions were further utilized for in situ ring-opening anionic polymerization of ecaprolactam with e-caprolactam magnesium bromide as a catalyst and N-acetyl-e-caprolactam as an activator. Some unique features of the obtained novel nylon-6/nanotubes composites are significantly increased thermal stability (T 5% up to 400 C), enhanced compression modulus and Izod impact strength of polymer blocks (by 25% and 150%, respectively) and advanced tensile strength and elongation of polymer films. Such an improvement in the properties of the composites in comparison with neat nylon-6 was gained by the addition of as little as 0.1-0.01 wt% of modified nanotubes.

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Two copolymers of N-acryloylpyrrolidine and N-vinylpyrrolidone with a different ratio of monomeric units and two homopolymers; poly-N-acryloylpyrrolidine and poly-N-vinylpyrrolidone, were synthesized to study the effect of the composition of macromolecular compounds (MMC) on their inhibiting p o w e r d u r i n g f o r m a t i o n o f g a s h y d r a t e s . T h e c o m p o s i t i o n o f t h e M M C w a s c o n f i r m e d by 1 H and 13 C NMR spectroscopy and the ratio of monomeric units in the copolymers was determinedwith the 1 H NMR spectra. The inhibiting power of the synthesized MMC was determined during hydrate formation.Liquid and gaseous hydrocarbon feedstock contains compounds (methane, ethane, propane, iso-and nbutanes, carbon dioxide, hydrogen sulfide) which form gas hydrates in certain thermobaric conditions in the presence of water. The formation of these technogenic hydrates is a serious process problem that arises in production, transport, and refining of hydrocarbon feedstock. Gas hydrates, which are solid crystalline substances, are deposited on the walls of pipes and equipment, which sharply reduces the flow rate of producing wells and process pipelines until they are totally plugged. Formation of gas hydrate plugs can result in many processes shutting down and thus cause important financial losses.Thermodynamic hydrate inhibitors (THI) are used for solving the problem of thermogenic gas hydrate formation in the Russian Federation. The main representatives of these inhibitors are water-soluble electrolyte salts, for example, calcium chloride, and low-molecular-weight alcohols such as methanol and mono-, di-, and triethylene glycol. THI shift three-phase gas -aqueous phase -gas hydrates equilibrium toward lower temperatures at a given pressure or higher pressures at a given temperature. This takes place because they compete with water molecules for formation of hydrogen bonds, and as a result, formation of hydrates becomes less probable from a thermodynamic point of view. Methanol is especially widely used among this kind of inhibitor.

D b r i e m e n t d'ktrophysique Relativiste et d e Cosmologie O b m t o i r e , 92190 Meudon, France AbsImacL Slatting from the equations of motion obeyed by fields, as they result from general approximations [they are m!ia to be of the following form [k2n(k)]+ = 0, for quasi bosons, and a similar equation for quasifermions] a lagmgian formalism is derived and, accordingly, consewed quantities are obtained. Next these fields are quantized and general expressions for the main observables are derived. Statistical mechanics of quasiparlicles then follow via the use of covariant Wigner functions.