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Низкотемпературная плазма. Модификация

Журнальные статьи

Almasian, Mohammad Reza; Yang, Chengdui; Xing, Zhi; et al. Development of a graphite low-temperature plasma source with dual-mode in-source fragmentation for ambient mass spectrometry // RAPID COMMUNICATIONS IN MASS SPECTROMETRY Volume: 24 Issue: 6 Pages: 742-748 Published: MAR 2010

A new low-temperature plasma (LTP), based on dielectric barrier discharge (DBD), has been developed as an alternative ionization source for ambient mass spectrometry. For organic samples, the source is able to produce two different fragmentation patterns which are selectable by an electrical switch. The two source modes are different only in the second electrodes: in configuration (A), bar-plate and in configuration (B), coaxial bar cylinder shapes are used. A disposable graphite probe is used as the first electrode, the same in both configurations, and a copper foil is used as the second electrode. The ionization source is applicable to gas and liquid samples, without any change being necessary in its design. Under optimal conditions, to take ethylbenzene as an example, a detection limit of less than 25 ng was obtained and a relative standard deviation (RSD) of 13.36% has been demonstrated for 50 ng of ethylbenzene (n = 11). We have found several interesting differences in the mass spectra of the tested volatile organic compounds (VOCs) in the two modes, which might be applicable in identification studies. We have investigated the effect of variation of the first electrode material and the second electrode length in mode B. Moreover, in this design the graphite electrode is capable of acting as a sample adsorbent, which is a new sampling method for LTP mass spectrometry (MS). This capability was investigated by adsorption of the selected VOCs onto the surface of the graphite electrode in a headspace solid-phase microextraction (SPME) system, and direct desorption and ionization of the samples by LTPMS.

Aoki, Takamichi; Ogoshi, Tomoki; Yamagishi, Tada-aki Chemically Responsive Supramolecular Structural Change of Pillar[5]arene Nanotubes // CHEMISTRY LETTERS Volume: 40 Issue: 8 Pages: 795-797 Published: AUG 5 2011

We prepared organo-nanotubes from pillar[5]arene molecules via intermolecular hydrogen bonding between the molecules. In the absence of guest molecules, formation of the nanotubes was observed simply by heating a solution of pillar[5]arene in a suitable solvent. In contrast, formation of the nanotubes did not occur in the presence of guest molecules.

Arico, Antonino Salvatore; Stassi, Alessandro; Gatto, Irene; et al. Arico, Antonino Salvatore; Stassi, Alessandro; Gatto, Irene; et al. Surface Properties of Pt and PtCo Electrocatalysts and Their Influence on the Performance and Degradation of High-Temperature Polymer Electrolyte Fuel Cells // JOURNAL OF PHYSICAL CHEMISTRY C Volume: 114 Issue: 37 Pages: 15823-15836 Published: SEP 23 2010

An investigation of the behavior of carbon-supported Pt and PtCo cathode electrocatalysts was carried out with the aim to evaluate their performance and resistance to degradation under high temperature (110-130 degrees C) operation in a polymer electrolyte membrane fuel cell (PEMFC) based on a new ionomer membrane (Aquivion). Nanosized Pt and PtCo catalysts with similar crystallite size (2.7-2.9 nm) were prepared by using a colloidal route. A suitable degree of alloying and a face-centered-cubic (fcc) structure were obtained for the PtCo catalysts by using a carbothermal reduction. The surface properties were investigated by X-ray photoelectron spectroscopy (XPS) and low-energy ion scattering spectroscopy (LE-ISS, (3)He(+) at 1 kV). The formation of a Pt skin layer on the surface of the alloy electrocatalyst was obtained by using a preleaching procedure. Furthermore, the amount of Pt oxides on outermost atomic layers was much smaller in the PtCo than in the Pt catalyst. These characteristics appeared to influence catalysts' performance and degradation. Accelerated tests (electrochemical cycling) at 130 degrees C in a pressurized PEMFC showed a better stability for the PtCo alloy as compared to Pt. Furthermore, better performance was obtained at high temperatures for the preleached PtCo/C as compared to the Pt/C cathode catalyst. At a moderate pressure of 1.5 bar (abs), maximum power densities of 800 and 700 mW cm(-2) at 110 degrees C (H(2)-O(2)) were achieved for the PtCo cathode with 50% and 25% relative humidity (RH), respectively, by using 0.3 mg Pt cm(-2) loading. At high pressure of 3 bar (abs), a maximum power density exceeding 1000 mW cm(-2) was obtained at 130 degrees C and 100% RH.

Ata, Seisuke; Kuboyama, Keiichi; Ito, Kenji; et al. Anisotropy and densification of polymer ultrathin films as seen by multi-angle ellipsometry and X-ray reflectometry // POLYMER Volume: 53 Issue: 4 Pages: 1028-1033 Published: FEB 17 2012

The chain conformations of cyclo-olefin polymer (COP) and polystyrene (PS) in less than 200-nm thick films on silicon wafers were investigated on the basis of the refractive index measured by multi-angle spectroscopic ellipsometry (MASE), and density measured by X-ray reflectometry (XRR). For both COP and PS, the density measured by XRR increases by decreasing the film thickness to below 50 nm. Densification may be caused by close packing of unentangled polymer chains in ultrathin films spincast from dilute solutions with polymer concentrations less than the overlap concentration (C*). For COP films, the refractive indices at incident angles of 45 degrees and 70 degrees measured by MASE agree well with those calculated by the Lorentz-Lorenz equation, indicating that densification of COP ultrathin films enhances their refractive indices. For PS films thinner than 50 urn, although the refractive index at an incident angle of 45 degrees agrees with a calculation based on the Lorentz-Lorenz equation, one at 70 degrees significantly deviates downward. A comparison of them with the results of quantum chemical calculation (QCC) suggested a plane-arrangement of benzene rings in PS ultrathin films, which was likely brought about by stacking of benzene rings and attractive interaction between pi-electrons in the benzene rings and the substrate surface.

Balmer, Jennifer A.; Mykhaylyk, Oleksandr O.; Armes, Steven P.; et al. Time-Resolved Small-Angle X-ray Scattering Studies of Polymer-Silica Nanocomposite Particles: Initial Formation and Subsequent Silica Redistribution // JOURNAL OF THE AMERICAN CHEMICAL SOCIETY Volume: 133 Issue: 4 Pages: 826-837 Published: FEB 2 2011

Small angle X-ray scattering (SAXS) is a powerful characterization technique for the analysis of polymer silica nanocomposite particles due to their relatively narrow particle size distributions and high electron density contrast between the polymer core and the silica shell. Time-resolved SAXS is used to follow the kinetics of both nanocomposite particle formation (via silica nanoparticle adsorption onto sterically stabilized poly(2-vinylpyridine) (P2VP) latex in dilute aqueous solution) and also the spontaneous redistribution of silica that occurs when such P2VP silica nanocomposite particles are challenged by the addition of sterically stabilized P2VP latex. Silica adsorption is complete within a few seconds at 20 degrees C and the rate of adsorption strongly dependent on the extent of silica surface coverage. Similar very short time scales for silica redistribution are consistent with facile silica exchange occurring as a result of rapid interparticle collisions due to Brownian motion; this interpretation is consistent with a zeroth-order Smoluchowski-type calculation.

Barbey, Raphael; Klok, Harm-Anton Room Temperature, Aqueous Post-Polymerization Modification of Glycidyl Methacrylate-Containing Polymer Brushes Prepared via Surface-Initiated Atom Transfer Radical Polymerization // LANGMUIR Volume: 26 Issue: 23 Pages: 18219-18230 Published: DEC 7 2010

This manuscript reports on the post-polymerization modification of poly(glycidyl methacrylate) (PGMA) and PGMA-co-poly(2-(diethylamino)ethyl methacrylate) (PGMA(x)-co-PDEAEMA(y)) (co)polymer brushes prepared via surface-initiated atom transfer radical polymerization (SI-ATRP). The aim of this study was to evaluate the ability of tertiary amine groups incorporated in the polymer brush to accelerate the ring-opening of the epoxide groups by primary amines and to facilitate the aqueous, room temperature post-polymerization modification of the brushes. Using Fourier transform infrared (FTIR) spectroscopy to monitor the ring-opening reaction of the epoxide groups, it was found that the incorporation of 2-(diethylamino)ethyl methacrylate (DEAEMA) groups in the PGMA brushes significantly accelerated the rate of the post-polymerization modification reaction with several model amines. The rate enhancement was dependent on the fraction of DEAEMA units incorporated in the copolymer brush. For example, whereas 24 h was necessary to obtain a conversion of approximately 40% for PGMA brushes immersed in a 1 M propylamine solution in water, the same conversion was reached, in identical reaction conditions, after 8 and 2 h with copolymer brushes containing 10 mol % and 25 mol % of DEAEMA along the copolymer chains, respectively. In a final series of proof-of-concept experiments, the feasibility of the glycidyl methacrylate containing brushes to act as substrates for protein immobilization was studied. Using FTIR spectroscopy and quartz crystal microbalance with dissipation (QCM-D) experiments, it could be demonstrated that the incorporation of DEAEMA units not only enhanced the rate of the protein immobilization reaction, but also resulted in higher protein binding capacities as compared to a PGMA homopolymer brush. These features make PGMAx-co-PDEAEMAy brushes very attractive candidates for the development of protein microarrays, among others.

Bogdanova, Yu. G.; Dolzhikova, V. D.; Tsvetkova, D. S.; et al. Contact angles as indicators of the polymer surface structure // JOURNAL OF STRUCTURAL CHEMISTRY Volume: 52 Issue: 6 Pages: 1187-1194 Published: DEC 2011

The capacities of the wetting method for the characterization of the surface structure of polymers and surfactant adsorption layers on polymer surfaces and also the determination of the energy characteristics of polymer surfaces at different interfaces, which are used to optimize the choice of polymers in the solution of actual practical problems, are demonstrated.

Bouteau, Murielle; Cantin, Sophie; Fichet, Odile; et al. Contribution Toward Comprehension of Contact Angle Values on Single Polydimethylsiloxane and Poly(ethylene oxide) Polymer Networks // LANGMUIR Volume: 26 Issue: 22 Pages: 17427-17434 Published: NOV 16 2010

The large application ranges of polydimethylsiloxane (PDMS) and poly(ethylene oxide) (PEO) based materials justify the importance of controlling polymer surface properties including morphology and wettability behavior. However, it appears that the reported contact angle values of PDMS surfaces show significant scattering which cannot always be interpreted in terms of sole chemical data. In addition, few values are reported concerning pure PEO surfaces, since the polymer generally swells in the presence of water. Thus, in order to correlate surface properties with sample preparation. several single PDMS and PEO polymer networks were synthesized with varying cross-linkers and different cross-linking densities. First, the sample surface topography was systematically analyzed by atomic force microscopy (AFM). It was proven that the removal process of the polymer film from the mold plays a significant role in surface topography according to the vitreous or rubbery state of the given polymer network at room temperature irrespective of mold surface treatment. AFM-scale smooth surfaces can be obtained for all the samples by removing them systematically from the mold at a temperature below the alpha-relaxation temperature. Dynamic water contact angles were then measured and the values analyzed as a function of cross-linker nature and cross-linking density.

Burke, Micheal; Blake, Alan; Povey, Ian M.; et al. Low sheet resistance titanium nitride films by low-temperature plasma-enhanced atomic layer deposition using design of experiments methodology // JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A Volume: 32 Issue: 3 Article Number: 031506 Published: MAY 2014

A design of experiments methodology was used to optimize the sheet resistance of titanium nitride (TiN) films produced by plasma-enhanced atomic layer deposition (PE-ALD) using a tetrakis(dimethylamino) titanium precursor in a N-2/H-2 plasma at low temperature (250 degrees C). At fixed chamber pressure (300 mTorr) and plasma power (300W), the plasma duration and N-2 flow rate were the most significant factors. The lowest sheet resistance values (163 Omega/sq. for a 20nm TiN film) were obtained using plasma durations similar to 40s, N-2 flow rates >60 standard cubic centimeters per minute, and purge times similar to 60 s. Time of flight secondary ion mass spectroscopy data revealed reduced levels of carbon contaminants in the TiN films with lowest sheet resistance (163 Omega/sq.), compared to films with higher sheet resistance (400-600 Omega/sq.) while transmission electron microscopy data showed a higher density of nanocrystallites in the low-resistance films. Further significant reductions in sheet resistance, from 163 Omega/sq. to 70 Omega/sq. for a 20nm TiN film (corresponding resistivity similar to 145 mu Omega.cm), were achieved by addition of a postcycle Ar/N-2 plasma step in the PE-ALD process.

Chen, Wei; Yang, Huicui; Wang, Rong; et al. Versatile Synthesis of Functional Biodegradable Polymers by Combining Ring-Opening Polymerization and Postpolymerization Modification via Michael-Type Addition Reaction // MACROMOLECULES Volume: 43 Issue: 1 Pages: 201-207 Published: JAN 12 2010

Various functional biodegradable polymers were readily prepared based on novel cyclic carbonate monomers, acryloyl carbonate (AC) and methacryloyl carbonate (MAC), by combining ring-opening polymerization (ROP) and Michael-type conjugate addition. AC and MAC monomers were synthesized in four straightforward steps from 1,1,1-tris(hydroxymethyl)ethane with good overall yields (ca. 40%). AC and MAC were able to copolymerize with epsilon-caprolactone (epsilon-CL) and D,L-lactide (LA) in toluene at 110 degrees C using stannous octoate as a catalyst yielding biodegradable copolymers with controlled (meth)acryloyl functional groups and molecular weights. The acryloyl groups were amenable to the Michael-type conjugate addition with varying thiol-containing molecules Such as 2-mercaptoethanol, 3-mercaptopropanoic acid, cysteamine, cysteine, and arginine-glycine-aspartic acid-cysteine (RGDC) peptide under mild conditions, to provide biodegradable materials with vastly different functionalities (e.g., hydroxyl, carboxyl, amine, amino acid, and peptides) and properties (e.g., hydrophilicity, cell adhesion). Notably, 100% functionalization was achieved with 2-mercaptoethanol, cysteamine and cysteine. Initial Cell Culture Studies demonstrated enhanced cell adhesion and growth oil films containing functional RGDC peptides as compared to those of the parent copolymer. Therefore, combination of ROP and Michael-type Conjugate addition provides a versatile access to diverse types of functional biodegradable materials.

Chen, Y.; Tang, X. L.; Chen, B. T.; et al.Low temperature plasma vapor treatment of thermo-sensitive poly(N-isopropylacrylamide) and its application // APPLIED SURFACE SCIENCE Volume: 268 Pages: 332-336 Published: MAR 1 2013

In this study, the novel methods of depositing poly(N-isopropylacrylamide) (PNIPAAm) coatings on the surface of glass slides and PS petri dish by plasma polymerization are provided. PNIPAAm can be obtained by plasma polymerization of N-isopropylacrylamide by using the self-made equipment of plasma vapor treatment. The samples were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and water contact angle. SEM analysis has revealed that the poly(N-isopropylacrylamide) (PNIPAAm) coatings were formed on the surface of the smooth glass slides. Further evaluation by using XPS, it has shown the presence of PNIPAAm. The wettability can be significantly modified by changing of the temperatures at above and below of the lower critical solution temperature (LCST) from the data of the contact angle test. These results have advantage for further application on the thermo-sensitive textile materials. On the deposition of PNIPAAm onto Polybutylene Terephthalate (PBT) melt-blown nonwovens in atmospheric pressure plasma, water permeability was significantly modified at around LCST. Due to the LCST is close to the temperature of human body, it has advantage on application of PBT melt-blown nonwovens.

Fischer, Hartmut Properties of Fracture Surfaces of Glassy Polymers: Chain Scission Versus Chain Pullout // JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS Volume: 48 Issue: 21 Pages: 2233-2237 Published: NOV 1 2010

Fresh fracture surfaces formed by tensile failure of craze in molded polystyrene (PS) bars have been compared with the molded surfaces of the same bars, using an atomic force microscope with a thermal probe and operated in local thermal analysis. The results indicate that molecular weight is much higher in the interior of the sample than at the surface. No evidence was found for degradation of the PS chains via chain scission during crazing. Alternative explanations for the low-molecular weights at the molded surface are discussed. (C) 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 2233-2237, 2010

Francisco, Kelly R.; Burgo, Thiago A. L.; Galembeck, Fernando Tribocharged Polymer Surfaces: Solvent Effect on Pattern Formation and Modification // CHEMISTRY LETTERS Volume: 41 Issue: 10 Special Issue: SI Pages: 1256-1258 Published: OCT 5 2012

Commonly used liquids have a powerful effect on the tribocharge patterns formed by rubbing polyethylene (PE) and poly(tetrafluoroethylene) surfaces. Solvents previously absorbed on PE specifically suppress positive tribocharge deposition. When applied to previously tribocharged surfaces, they also behave as charge-suppressing agents or transfer media. All these unprecedented results verify a new mechanochemical model that was recently introduced to explain the hitherto challenging problem of triboelectricity formation.

Gallo, Santiago Corujeira; Dong, Hanshan EBSD and AFM observations of the microstructural changes induced by low temperature plasma carburising on AISI 316 // APPLIED SURFACE SCIENCE Volume: 258 Issue: 1 Pages: 608-613 Published: OCT 15 2011

Low temperature plasma carburising (LTPC) has been increasingly accepted as a hardening process for austenitic stainless steels because it produces a good combination of tribological and corrosion properties. The hardening mechanism is based on the supersaturation of the austenitic structure with carbon, which greatly hardens the material, significantly expands the fcc unit cell, produces high levels of compressive residual stresses and, ultimately, leads to the occurrence of deformation bands and rotation of the crystal lattice. The microstructural changes introduced during plasma carburising have a significant impact on the mechanical, tribological and corrosion performance and, for this reason, the microstructure of expanded austenite or S-phase has been extensively studied. However, modern surface characterisation techniques could provide new insights into the formation mechanism of S-phase layers. In this work, backscattered electron diffraction and atomic force microscopy were used to characterise the surface layers of expanded austenite produced by LTPC in an active screen furnace. Based on the experimental results, the plastic deformation, its dependence on crystallographic orientation, the evolution of grain boundaries, and their effects on mechanical, tribological and corrosion properties are discussed.

Gilman, A. B.; Yablokov, M. Yu; Kuznetsov, A. A. Modification of carbon nano-objects in low-temperature plasma for use in polymer nanocomposites // HIGH ENERGY CHEMISTRY Volume: 46 Issue: 4 Pages: 219-228 Published: JUL 2012

Literature on the modification of carbon nanotubes and nanofibers in a low-temperature plasma has been surveyed. Basic techniques for the treatment of nano-objects in discharges of various types and various devices used in these processes have been described. Instrumental methods for the investigation of plasma-modified carbon nanotubes and nanofibers and the properties of composites prepared from them with different polymer matrices have been discussed.

Guo Xingmei; Yang Yongzhen; Zhao Xuexia; et al. Carbon spheres surface modification and dispersion in polymer matrix // APPLIED SURFACE SCIENCE Volume: 261 Pages: 159-165 Published: NOV 15 2012

Polymer/carbon spheres (CSs) composite materials, in which polymer was used as continuous phase and CSs as dispersed phase, were synthesized by in situ bulk polymerization. In order to improve CSs dispersibility in polymer matrix and compatibility with polymer matrix, the functional double bonds were introduced onto the surface of CSs by covalent and non-covalent method. Covalent functionalization was accompolished through mixed acid oxidation and subsequent reaction with acryloyl chloride. Field-emission scanning electron microscopy, Fourier-transform Infrared spectrometry and thermogravimetry were used to characterize the morphology, structure and effect of functionalization of CSs. Vinyl-functionalized CSs by acryloyl chloride were well dispersed in organic solvents, such as DMF, acetone and chloroform. Non-covalent functionalization by surfactant was accompolished by electrostatic interaction. Covalent and non-covalent functionalization enabled CSs to be homogeneously dispersed in poly(methyl methacrylate) (PMMA) matrix with good compatibility. These studies lay the foundation of preparing the non-close packed three-dimensional carbon-based photonic crystals.

Guo, Yiguang; Chen, Ting; Zhao, Na; et al. Dilational properties of gemini surfactant/polymer systems at the air-water surface // COLLOID AND POLYMER SCIENCE Volume: 291 Issue: 4 Pages: 845-854 Published: APR 2013

The surface properties of mixed system containing gemini anionic surfactant 1,2,3,4-butanetetracarboxylic sodium, 2,3-didodecyl ester and partly hydrolyzed polyacrylamide were investigated by surface tension measurements and oscillating bubble methods. The influences of surfactant concentration, dilational frequency, temperature, pH, as well as salts on dilational modulus were explored. Meanwhile, the interfacial tension relaxation method was employed to obtain the characteristic time of surface relaxation process. The polymers play important roles in changing the interfacial properties especially at lower surfactant concentration. The possible mechanism of the polymer in changing the interfacial properties is proposed. Both the hydrophobic and electrostatic interaction among the surfactants and polymers dominate the surface properties of mixed system. These dynamic properties are of fundamental interest in understanding the structure of adsorption layers, dynamics of surfactant molecules, and their interaction with polymers at the surface.

Haraguchi, Kazutoshi; Li, Huan-jun; Ren, Huai-yin; et al. Modification of Nancomposite Gels by Irreversible Rearrangement of Polymer/Clay Network Structure through Drying // MACROMOLECULES Volume: 43 Issue: 23 Pages: 9848-9853 Published: DEC 14 2010

Nanocomposite gels (NC gels) have a unique organic polymer)/inorganic (clay) network structure which causes them to exhibit excellent mechanical and swelling properties. It was found that dried and reswollen NC gels showed higher tensile moduli and strengths and low elongations at break as well as lower swelling when compared to those of NC gels as-prepared. The modification in properties brought about by drying was observed in all NC gels, regardless of the type of polymer used and the clay concentration. These changes were attributed to the irreversible rearrangement of the polymer/clay network structure in which additional cross-links arc formed due to additional contacts between polymer chains and clay and the strengthening of preformed loose contacts in the concentrated state. The rearranged network structure remained almost unchanged on repeated drying and heating in the dried state. In contrast, conventional chemically cross-linked hydrogels showed no changes in properties in response to drying treatment.

Jeong, Hoon Eui; Lee, Jin-Kwan; Kwak, Moon Kyu; et al. Effect of leaning angle of gecko-inspired slanted polymer nanohairs on dry adhesion // APPLIED PHYSICS LETTERS Volume: 96 Issue: 4 Article Number: 043704 Published: JAN 25 2010

We present analysis of adhesion properties of angled polymer nanohairs with a wide range of leaning angles from 0 degrees to 45 degrees and ultraviolet (UV)-curable polyurethane acrylate (PUA) materials of two different elastic moduli (19.8 and 320 MPa). It is demonstrated that shear adhesion and adhesion hysteresis can be greatly enhanced by increasing the leaning angle of nanohairs both for soft and hard materials due to increased contact area and reduced structural stiffness.

Kang, Sung Min; You, Inseong; Cho, Woo Kyung; et al. One-Step Modification of Superhydrophobic Surfaces by a Mussel-Inspired Polymer Coating // ANGEWANDTE CHEMIE-INTERNATIONAL EDITION Volume: 49 Issue: 49 Pages: 9401-9404 Published: 2010

Keating, M.; Song, S.; Wei, G.; et al. Ordered Silver and Copper Nanorod Arrays for Enhanced Raman Scattering Created via Guided Oblique Angle Deposition on Polymer // JOURNAL OF PHYSICAL CHEMISTRY C Volume: 118 Issue: 9 Pages: 4878-4884 Published: MAR 6 2014

We report the manufacture of ordered silver and copper nanorod arrays for surface-enhanced Raman scattering using oblique angle deposition (OAD) on prepatterned polymer sheets. It was found that the patterned polymer substrate defined nucleation sites which guided subsequent growth of nanorods. Enhanced surface-enhanced Raman spectroscopy (SERS) intensities of the Raman probe molecule trans-1,2-bis(4-pyridyl)ethylene (BPE) were found for Ag arrays on polymer, up to about 10 times that of the Ag-silica control. The SERS response of Ag nanorod arrays of different structures was investigated alongside results obtained from discrete dipole approximation simulations. This revealed that narrow gaps between nanorods, formed by guided nucleation during OAD, were responsible for this dramatic enhancement. Ordered Cu nanorod arrays were also successfully fabricated, producing a SERS intensity about 3 times that of Cu on silicon for both BPE and another Raman probe-rhodamine B isothiocyanate (RBITC)-highlighting the potential of this large-scale, low-cost, SERS-active substrate.

Kimani, Solomon M.; Thompson, Richard L.; Hutchings, Lian R.; et al. Multihydroxyl End Functional Polyethylenes: Synthesis, Bulk and Interfacial Properties of Polymer Surfactants // MACROMOLECULES Volume: 47 Issue: 6 Pages: 2062-2071 Published: MAR 25 2014

Multihydroxyl end functional polyethylenes have been prepared with controlled molecular weight, microstructure, and functionalization. These materials, designed as interfacially active blend additives for polar interfaces, are thermally stable up to similar to 250 degrees C and to have similar crystallinity and dynamics to their unfunctionalized homopolymer analogues. The polymers segregated strongly to silicon oxide interfaces, with adsorbed layers forming spontaneously at annealed polymer interfaces, having surface excess concentrations approaching 2R(g) and a maximum areal density of approximately 0.6 adsorbed chains per nm(2). This interfacial activity is achieved almost without detriment to the bulk physical properties of the polymer as evidenced by thermal analysis, quasi-elastic neutron scattering, and small-angle neutron scattering (SANS). SANS experiments show little evidence for aggregation of the dihydroxyl functionalized polymers in blends with PE homopolymers, which is thought to explain why these additives have particularly strong interfacial adsorption, even at relatively high concentrations. A modest level of segregation of the additives to exposed blend surfaces was also seen, particularly when the additive molecular weight was significantly lower than that of the matrix. We attribute this to a combination of the relatively low molecular weight of the additives and the marginally lower surface energy associated with deuterated polymers.

Korampally, Venumadhav; Mamidi, Vamshi Krishna; Harris, Bryant; et al. Sub-minute formation of supported nanoporous mesoscale patterns programmed by surface energy // JOURNAL OF COLLOID AND INTERFACE SCIENCE Volume: 364 Issue: 2 Pages: 546-554 Published: DEC 15 2011

We demonstrate an original and powerful concept for elaborating spontaneous, high fidelity patterns of nanoporosity from nanoscale building blocks using patterned surface chemistry (i.e., "surface energy gating") to corral the growth of colloidal structures at a solid surface. Composite films consisting of polymethylsilsesquioxane nanoparticles uniformly dispersed in polypropylene glycol polymer were examined at temperatures beyond the decomposition of the polymer as a function of the substrate surface energy to clarify nanoparticulate ensemble behavior. The principle behind this colloidal assembly can be understood by taking into consideration the entropy and enthalpy dictating the mutual interactions between substrate surface, polymeric solvent, and dispersed colloids in the decomposition regime. The relevance of this research is shown by demonstrating how the principle of surface energy gating can be utilized to achieve spontaneous and controllable spatial patterns of nanoporous, high surface area thin films in a cost-effective and energy-efficient manner via brief thermal exposure. The simplicity and general nature of this methodology are further exemplified by showing the facility with which high-contrast fluorescent bioconjugate arrays can be prepared from nanoporous organosilicate patterns.

Li, Lei; Niu, Shu-Yun; Jin, Jing; et al. A series of M-M ' heterometallic coordination polymers: syntheses, structures and surface photoelectric properties (M=Ni/Co, M '=Cd/Zn) // JOURNAL OF SOLID STATE CHEMISTRY Volume: 184 Issue: 5 Pages: 1279-1285 Published: MAY 2011

Four new heterometallic polymers, [NiCd(mal)(2)(H2O)(2)]n center dot 2nH(2)O 1, [NiZn2(Hcit)(2)(H2O)(2)]n 2, [CoCd2 (Hcit)(2)(H2O)(2)]n 3,[CoZn2(Hcit)(2)(H2O)(2)]n 4 (H(2)mal=malonic acid, H(4)cit=citric acid) were synthesized and characterized. The photoelectric properties of the polymers were discussed by the surface photovoltage spectroscopy (SPS). The structural analyses indicate 1 is a Ni-Cd heterometallic polymer with 3D structure bridged by the mal(2-) group. 2-4 are all heterometallic polymers with 2D structures bridged by the Hcit(3-) group. The results of SPS for the four polymers reveal that there are wide photovoltage response bands in the range of 300-800 nm, which indicates that they all possess photoelectric conversion properties. By the introduction of the other metals, the SPS of heterometallic polymers are broadened obviously than the SPS of monometallic complexes. Moreover, the relationships between SPS and UV-Vis absorption spectra have been discussed.

Lin, Janice; Szymanski, John; Searson, Peter C.; et al. Effect of a Polymer Cushion on the Electrical Properties and Stability of Surface-Supported Lipid Bilayers // LANGMUIR Volume: 26 Issue: 5 Pages: 3544-3548 Published: MAR 2 2010

A robust biomimetic cell membrane platform is Critical for mechanistic studies of membrane protein channels. While polymer cushions are believed to incorporation of membrane proteins in such a platform, a systematic characterization and optimization of such cushions is rarely performed. Here, we examine the influence of a polymer cushion on the electrical properties of supported 1,2-diphytanoyl-sn-glycero-3-phosphocholine (CPhPC) bilayers produced via a Langmuir-Blodgett deposition/vesicle fusion assembly process on single-crystal silicon. We show that the resistance of DPhPC bilayers is maximized at the calculated crossover concentration of the polymer (5.9 mol % PEG-lipids). Additionally, these bilayers are sufficiently stable to allow impedance analyses to be performed for nearly 3 weeks. These studies reveal the optimal PEG concentration that yields electrically robust bilayers and demonstrate the utility of the platform for future studies of membrane protein channels and membrane active peptides.

Liu, Yueying; Ma, Xiaoxiao; Lin, Ziqing; et al.Imaging Mass Spectrometry with a Low-Temperature Plasma Probe for the Analysis of Works of Art // ANGEWANDTE CHEMIE-INTERNATIONAL EDITION Volume: 49 Issue: 26 Pages: 4435-4437 Published: 2010

Mason, Christopher R.; Maynard-Atem, Louise; Heard, Kane W. J.; et al. Enhancement of CO2 Affinity in a Polymer of Intrinsic Microporosity by Amine Modification // MACROMOLECULES Volume: 47 Issue: 3 Pages: 1021-1029 Published: FEB 11 2014

Nitrile groups in the polymer of intrinsic microporosity PIM-1 were reduced to primary amines using borane complexes. In adsorption experiments, the novel amine PIM-1 showed higher CO2 uptake and higher CO2/N-2 sorption selectivity than the parent polymer, with very evident dual-mode sorption behavior. In gas permeation with six light gases, the individual contributions of solubility and diffusion to the overall permeability was determined via time-lag analysis. The high CO2 affinity drastically restricts diffusion at low pressures and lowers CO2 permeability compared to the parent PIM-1. Furthermore, the size-sieving properties of the polymer are increased, which can be attributed to a higher stiffness of the system arising from hydrogen bonding of the amine groups. Thus, for the H-2/CO2 gas pair, whereas PIM-1 favors CO2, amine-PIM-1 shows permselectivity toward H-2, breaking the Robeson 2008 upper bound.

Nishi, Kengo; Asai, Hanako; Fujii, Kenta; et al. Small-Angle Neutron Scattering Study on Defect-Controlled Polymer Networks // MACROMOLECULES Volume: 47 Issue: 5 Pages: 1801-1809 Published: MAR 11 2014

Tetra-PEG gels are classified to near-"ideal" networks with significantly low inhomogeneities, which were confirmed by small-angle neutron scattering (SANS). In this study, we systematically introduced two types of defects into Tetra-PEG gels and investigated effects of defects on structure. First, we prepared defect-rich networks by simply reducing prepolymer concentration, and observed the evolution of network structure by time-resolved SANS during gelation process. In this case, both the scattering intensity and the correlation length increased with reaction time in the phi < phi* region, while they scarcely changed in the phi > phi* region. Here, phi and phi* are the polymer volume fractions at observation and that at chain-overlap concentration, respectively. Second, we prepared "p-tuned" Tetra-PEG gels by tuning the reaction probability, p, and soaked them in water to expose the inhomogeneities. It was revealed that SANS profiles of as-prepared gels did not change noticeably, while those of swollen gels systematically changed with decreasing p. On the basis of these results, we discuss the relationship between the defects of polymer network and inhomogeneities by using simple schematic pictures of polymer network.

Pack, Seongchan; Kashiwagi, Takashi; Cao, Changhong; et al. Role of Surface Interactions in the Synergizing Polymer/Clay Flame Retardant Properties // MACROMOLECULES Volume: 43 Issue: 12 Pages: 5338-5351 Published: JUN 22 2010

Purpose - The purpose of this paper is to modify the surface property of polyacrylate latex films using only small amounts of fluorinated acrylate and to optimise the results of such a modification. Design/methodology/approach - The core-shell particles with polyacrylate rich in core and containing fluorinated polymer rich in shell are prepared by a two-stage semi-continuous emulsion polymerisation under kinetically controlled conditions. The surface properties of the latex films produced from the core-shell particles are investigated by optical goniometer measurement as well as contact angle method. Findings - The latex films produced from the core-shell particles exhibited surface energy of around 10 mN/m. The angle resolved X-ray photoelectron spectrum measurements showed an increased average fluorine concentration in a surface layer thickness of a few nanometres, when compared to the fluorine concentration in the bulk. Research limitations/implications - Methyl methacrylate, butyl acrylate and N-methylol acrylamide monomers are used as co-monomer to form the shell with fluoroalkyl methacrylate. By preparing core-shell emulsion with a fluoropolymer in the shell phase, the surface property of polyacrylate latex films is efficiently modified by using only small amounts of fluorinated acrylate monomer. Practical implications - The method developed provided a simple and practical solution to improving the surface property of polyacrylate latex films. Originality/value - The method for enhancing surface property of polyacrylate latex films is novel and can find numerous applications in surface coating.

Pancheshnyi, S.; Biagi, S.; Bordage, M. C.; et al. The LXCat project: Electron scattering cross sections and swarm parameters for low temperature plasma modeling // CHEMICAL PHYSICS Volume: 398 Pages: 148-153 Published: APR 4 2012

LXCat is a dynamic, open-access, website for collecting, displaying, and downloading ELECtron SCATtering cross sections and swarm parameters (mobility, diffusion coefficient, reaction rates, etc.) required for modeling low temperature, non-equilibrium plasmas. Contributors set up individual databases, and the available databases, indicated by the contributor's chosen title, include mainly complete sets of electron-neutral scattering cross sections, although the option for introducing partial sets of cross sections exists. A database for measured swarm parameters is also part of LXCat, and this is a growing activity. On-line tools include options for browsing, plotting, and downloading cross section data. The electron energy distribution functions (edfs) in low temperature plasmas are in general non-Maxwellian, and LXCat provides an option for execution of an on-line Boltzmann equation solver to calculate the edf in homogeneous electric fields. Thus, the user can obtain electron transport and rate coefficients (averages over the edfs) in pure gases or gas mixtures over a range of values of the reduced electric fields strength, E/N, the ratio of the electric field strength to the neutral density, using cross sections from the available databases. New contributors are welcome and anyone wishing to create a database and upload data can request a username and password. LXCat is part of a larger, community-wide effort aimed at collecting, evaluating, and sharing data relevant to modeling low temperature plasmas. To illustrate the utility of LXCat in this context, we compare electron swarm parameters in argon calculated using the different compilations of cross sections presently available on LXCat. These compilations include quite different groupings of excited states, yet lead to swarm parameters in good agreement. LXCat is available at http://www.lxcat.laplace.univ-tlse.fr.

Porcar, Lionel; Hong, Kunlun; Butler, Paul D.; et al. Intramolecular Structural Change of PAMAM Dendrimers in Aqueous Solutions Revealed by Small-Angle Neutron Scattering // JOURNAL OF PHYSICAL CHEMISTRY B Volume: 114 Issue: 5 Pages: 1751-1756 Published: FEB 11 2010

Small-angle neutron scattering (SANS) experiments were carried out to investigate the structure of aqueous (D(2)O) G4 PAMAM dendrimer solutions as a function of molecular protonation and dendrimer concentration. Our results indicate unambiguously that, although the radius of gyration R(G), remains nearly invariant, the dendrimer radial density profile rho(r) decreases in the dendrimer core with a continuous increase in protonation. This discovery also suggests that R(G), which is commonly adopted by numerous simulation and experimental works in describing the global dendrimer size, is not suitable as the index parameter to characterize the dendrimer coil formation change. We also found that R(G) and rho(r), for dendrimers dissolved in both neutral and acidified solutions, remain nearly constant over the studied concentration range. We further demonstrate that the outcome of the widely used Guinier method is questionable for extracting R(G) in the concentration range studied. Our results reveal the polymer colloid structural duality as benchmarks for future experimental and theoretical studies and provide a critical step toward understanding drug encapsulation by ionic bonds.

Potts, S. E.; Keuning, W.; Langereis, E.; et al. Low Temperature Plasma-Enhanced Atomic Layer Deposition of Metal Oxide Thin Films // JOURNAL OF THE ELECTROCHEMICAL SOCIETY Volume: 157 Issue: 7 Pages: P66-P74 Published: 2010

Many reported atomic layer deposition (ALD) processes are carried out at elevated temperatures (> 150 degrees C), which can be problematic for temperature-sensitive substrates. Plasma-enhanced ALD routes may provide a solution, as the ALD temperature window can, in theory, be extended to lower deposition temperatures due to the reactive nature of the plasma. As such, the plasma-enhanced ALD of Al(2)O(3), TiO(2), and Ta(2)O(5) has been investigated at 25-400 degrees C using [Al(CH(3))(3)], [Ti(O(i)Pr)(4)], [Ti(Cp(Me))(O(i)Pr)(3)], [TiCp(*)(OMe)(3)], and [Ta(NMe(2))(5)] as precursors. An O(2) plasma was employed as the oxygen source in each case. We have demonstrated metal oxide thin-film deposition at temperatures as low as room temperature and compared the results with corresponding thermal ALD routes to the same materials. The composition of the films was determined by Rutherford backscattering spectroscopy. Analysis of the growth per cycle data and the metal atoms deposited per cycle revealed that the growth per cycle is strongly dependent on the film density at low deposition temperatures. Comparison of these data for Al(2)O(3) ALD processes in particular, showed that the number of Al atoms deposited per cycle was consistently high down to room temperature for the plasma-enhanced process but dropped for the thermal process at substrate temperatures lower than 250 degrees C.

Sergan, Vassili V.; Sergan, Tatiana A.; Bos, Phillip J. Control of the molecular pretilt angle in liquid crystal devices by using a low-density localized polymer network // CHEMICAL PHYSICS LETTERS Volume: 486 Issue: 4-6 Pages: 123-125 Published: FEB 12 2010

We developed a method to fabricate liquid crystal (LC) devices with variable pretilt angle (2-90 degrees) which involves voltage application during the UV-light-induced polymerization of a photo-reactive monomer added in concentrations below 1%. Polymerization follows the application of the high voltage, which facilitates the motion of the monomer to the cell substrates. Control of the pretilt angle is accomplished through the formation of a thin polymer layer near the cell substrates, which stabilizes the LC orientation. The pretilt angle can be controlled over a small area of the sample, which allows for the fabrication of LC lenses and prisms.

Shiraki, Tomohiro; Dawn, Arnab; Tsuchiya, Youichi; et al. Thermo- and Solvent-Responsive Polymer Complex Created from Supramolecular Complexation between a Helix-Forming Polysaccharide and a Cationic Polythiophene // JOURNAL OF THE AMERICAN CHEMICAL SOCIETY Volume: 132 Issue: 39 Pages: 13928-13935 Published: OCT 6 2010

The helical structure is one of key structural components for both biological systems and artificial chiral systems. So far, we have succeeded in fabricating "tight" insulated molecular wires consisting of a triple-stranded cohelical structure formed through supramolecular wrapping of synthetic polymers by a helix-forming polysaccharide (schizophyllan). Herein, we have designed a new modified polysaccharide (Curoeg) to form a "loose" macromolecular complex with a conjugated polymer (CP) that allows structural changes in response to external stimuli. Cur-oeg forms a helical complex with an achiral cationic polythiophene (PT1), and the effective conjugation length is changed by temperature, showing a large absorption peak shift from 403 to 482 nm between 85 and 5 degrees C. According to the change in the conjugation system, the fluorescence and the induced circular dichroism show the continuous spectral shifts under temperature control. The color changes in the absorption and the fluorescence are detectable with observation by the naked eye and are reversibly controlled under thermal cycles, indicating that this system has the function of a "molecular thermometer". It is shown that the induced thermoresponsiveness is associated with structural rearrangement of the helical conformation of PT1 in the complex. Moreover, another unique responsiveness is discovered for the film state: that is, the film color is varied when it is exposed to the vapor of water or methanol (vaporchromism), resulting from the structural change of PT1 occurring even in the film state. These flexible molecular motions in both the solution state and the film state can be applicable to the design of CP-based smart sensors, polarized materials, switching devices, etc.

Sohn, Eun-Ho; Kim, Byoung Gak; Chung, Jae-Seung; et al. Comb-like polymer blends of poly(oxyethylene)s with CH3-terminated and CF3-terminated alkylsulfonylmethyl side chains: Effect of terminal CF3 moiety on the surface properties of the blends // JOURNAL OF COLLOID AND INTERFACE SCIENCE Volume: 343 Issue: 1 Pages: 115-124 Published: MAR 1 2010

The surface properties of comb-like polymer blends of poly(oxyethylene)s having CH3-terminated and CF3-terminated alkylsulfonylmethyl side chains were studied. These side chains were found to be well oriented on the surface of the blends, while being phase separated, following various surface morphologies composed of holes, islands, or connected islands, because of their immiscibility resulting from their different polarities. The domain size of each polymer on the blend surface was found to be almost linearly proportional to the bulk compositions of the mixture, and the CF3-terminated alkylsulfonylmethyl side chain domains were found to be located in the lower region of the surface. The polar CF3-terminal groups in the lower regions were deemed to control the surface properties, because the contact angles and stick-slip behaviors of the blends containing more than 40 mol% of poly(oxyethylene) with CF3-terminated side chains were almost identical.

Terashima, Takaya; Motokawa, Ryuhei; Koizumi, Satoshi; et al. In Situ and Time-Resolved Small-Angle Neutron Scattering Observation of Star Polymer Formation via Arm-Linking Reaction in Ruthenium-Catalyzed Living Radical Polymerization // MACROMOLECULES Volume: 43 Issue: 19 Pages: 8218-8232 Published: OCT 12 2010

In situ and time-resolved small-angle neutron scattering (SANS) was employed for the elucidation of star polymer formation mechanism via linking reaction of living linear polymers in ruthenium-catalyzed living radical polymerization. Here, methyl methacrylate (M MA) was first polymerized with R-Cl/RuCl2(PPh3)(3)/tribuylamine (n-Bu3N) initiating system, followed by the addition of ethylene glycol dimethacrylate (EGDMA: 3) as a linking agent. After the in situ addition of a small amount of 3 to living linear PM MA, the SANS analysis revealed the following three steps: (process II-1) formation of block copolymers (4) and competitive formation of the small star polymers via the linking reaction of 4 and 4: (process II-2) star-star linking oldie small star polymers into star polymers and putting 4 into the core of the star polymers, leading to formation or the microgel-core star polymers; (process II-3) growth of the microgel-core star polymers (5) via placement of 4 into the microgel-core star polymers. Furthermore. the SANS profiles, obtained as a function of polymerization time, were quantitatively analyzed with a core-shell spherical model in order to determine the microstructures of the star polymers: The final reaction product had an average radius of microgel-core (similar to 1 nm), and average arm numbers N similar to 17.

Timakova, K. A.; Tarasov, A. V.; Fedotov, Yu. A.; et al. Modification of polymer films, coatings, and membranes // PETROLEUM CHEMISTRY Volume: 52 Issue: 7 Pages: 505-513 Published: DEC 2012

Analysis of the modern scientific developments and practical achievements in the area of polymer films, coatings, and membrane modification is presented in this review. Peculiarities of physical and chemical modification methods are considered. Some examples of their effective applications are presented. The most promising methods of polymer modification are demonstrated.

Vortmann, Britta; Nowak, Sascha; Engelhard, Carsten Rapid Characterization of Lithium Ion Battery Electrolytes and Thermal Aging Products by Low-Temperature Plasma Ambient Ionization High-Resolution Mass Spectrometry // ANALYTICAL CHEMISTRY Volume: 85 Issue: 6 Pages: 3433-3438 Published: MAR 19 2013

Lithium ion batteries (LIBs) are key components for portable electronic devices that are used around the world. However, thermal decomposition products in the battery reduce its lifetime, and decomposition processes are still not understood. In this study, a rapid method for in situ analysis and reaction monitoring in LIB electrolytes is presented based on high-resolution mass spectrometry (HR-MS) with low-temperature plasma probe (LTP) ambient desorption/ionization for the first time. This proof-of-principle study demonstrates the capabilities of ambient mass spectrometry in battery research LTP-HR-MS is ideally suited for qualitative analysis in the ambient environment because it allows direct sample analysis independent of the sample size, geometry, and structure. Further, it is environmental friendly because it eliminates the need of organic solvents that are typically used in separation techniques coupled to mass spectrometry. Accurate mass measurements were used to identify the time-/condition-dependent formation of electrolyte decomposition compounds. A LIB model electrolyte containing ethylene carbonate and dimethyl carbonate was analyzed before and after controlled thermal stress and over the course of several weeks. Major decomposition products identified include difluorophosphoric acid, monofluorophosphoric acid methyl ester, monofluorophosphoric acid dimethyl ester, and hexafluorophosphate. Solvents (i.e., dimethyl carbonate) were partly consumed via an esterification pathway. LTP-HR-MS is considered to be an attractive method for fundamental LIB studies.

Xing, Zhi; Wang, Juan; Han, Guojun; et al. Depth Profiling of Nanometer Coatings by Low Temperature Plasma Probe Combined with Inductively Coupled Plasma Mass Spectrometry // ANALYTICAL CHEMISTRY Volume: 82 Issue: 13 Pages: 5872-5877 Published: JUL 1 2010

The development of material science increasingly calls for rapid characterization methods with low limits of detection and high spatial resolution. Here we report a depth profile analysis method for thin layer coatings by combining low temperature plasma (LW) probe with inductively coupled plasma mass spectrometry (ICP-MS). The LTP probe with diameter of several tens of micrometers served as a tool for mass removal, which is generated by the discharge in a quartz capillary at ambient condition. The sample material is ablated by the LTP probe and converted into an aerosol, and transported by a carrier gas flow to the ICP-MS, where the decomposed and ionized aerosol particles are analyzed with high sensitivity. Scanning electron microscope (SEM) micrographs reveal that the trace after ablation by the LTP probe is a hole with a diameter less than 10 mu m. A lateral resolution of approximately 200 mu m has been achieved by analyzing an electron component with interval metal stripes. Depth profiling of a 100 nm single layer sample and a multiple layer sample (100 nm Al/250 nm SiO(2)/100 nm Au/50 nm Cr) on a silicon substrate have been successfully performed at ambient condition. The present method offers unique advantages in terms of high spatial resolution, fast analysis speed and ease of implementation. It might be considered a complementary technique to existing depth profiling methods such as GD-MS/OES, AES, and SIMS. In addition, the simple-to-fabricate LTP probe is easily coupled to various other elemental analysis tools for thin layer or direct solid sample analysis in micro area.

Zhang, Z.; Zuo, C. C.; Cao, Q. Q.; et al. Adsorption Properties of Comb-Like Polymer on Nanotube Surface // POLYMER SCIENCE SERIES A Volume: 54 Issue: 1 Pages: 39-47 Published: JAN 2012

The adsorption and wrapping process of a single flexible comb-like polymer to a single wall nanotube was studied by Molecular Dynamics simulation of a coarse-grained model. We varied the grafting density and length of the side chains, the radius of the nanotube and strength of interaction between the monomers of nanotube and side chains of polymer brush. We investigated the structural and dynamical characters of interactions of the nanotube-polymer composite, such as the effect of Lennard-Jones energy parameter epsilon(LJ) and the nanotube radius on the adsorption behavior and how the wrapping conformation is affected by the structure of the polymer brush. The simulation results indicate that single comb-like polymer with flexible backbone tends to adsorb and wrap around the nanotube, when the interaction energy exceeds a critical value. The monomer adsorption ratio, interaction energy profiles and moment of inertia are obtained. The helical wrapping only occurs when the interaction energy is large enough. Also, the influence of the polymer structure on the conformational behavior is analyzed. This work underscores design elements important for engineering well-defined nanotube-polymer nanocomposite.

Zhou, Qi; Pramoda, K. P.; Lee, Jong-Min; et al. Role of interface in dispersion and surface energetics of polymer nanocomposites containing hydrophilic POSS and layered silicates // JOURNAL OF COLLOID AND INTERFACE SCIENCE Volume: 355 Issue: 1 Pages: 222-230 Published: MAR 1 2011

Three different hydrophilic nanofillers - natural and synthetic layered silicate as well as octaammonium polyhedral oligomeric silsesquioxane (POSS) - were incorporated into polyamide-6 by a solution-mixing method. The surfaces of the resulting polymer nanocomposites were characterized by X-ray diffraction, polarized optical microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and contact angle measurements. All polymer nanocomposites displayed enhancement in surface hydrophilicity as well as increase in surface free energy due to surface enrichment of the nanofillers. The degree of enhancement was found to depend on both nanofiller type and dispersion state. Interfacial interactions in the form of hydrogen bonding played an important role in affecting the dispersion state of the layered silicates. Exfoliated layered silicates caused a larger increase in hydrophilicity than aggregated layered silicate. On the other hand, aggregated POSS molecules were able to induce a large increase in hydrophilicity. Significant spreading of water was also observed on surfaces containing POSS molecules. Surface models have been proposed to explain these phenomena.


Приводятся некоторые результаты исследования факторов, оказывающих влияние на условия формирования адгезионного контакта и методов повышения адгезионной прочности полимеров к металлу; исследовано влияние электромагнитных волн сверхвысокочастотного диапазона на адгезионную способность полимерных материалов, которые продемонстрировали высокую эффективность использования электромагнитного излучения для нетепловой модификации полимеров.


Агеев Е.П., Матушкина Н.Н., Струсовская Н.Л. ПЕРВАПОРАЦИОННЫЕ СВОЙСТВА ПОЛИАМИДНЫХ МЕМБРАН И ИХ ЗАВИСИМОСТЬ ОТ ТОНКИХ РАЗЛИЧИЙ В СТРУКТУРЕ ПОЛИМЕРА И УСЛОВИЙ ЭКСПЕРИМЕНТА // Сорбционные и хроматографические процессы. – 2010, № 4 (10). - С. 606-618.

В качестве первапорационных мембран для разделения модельной смеси вода-изопропанол во всем диапазоне концентраций использовали ароматические полиамиды, а также мембраны различной площади. Показано, что набухание пленок в процессе жидкофазного разделения вызывает структурные изменения полимеров, динамика которых может быть нелинейна. Процесс оказался весьма чувствителен к тонким различиям в структуре полимера,таким как изомерный состав фрагментов, незначительные изменения концентрации ионогенных групп, сополимеры и механическая смесь гомополимеров такого же состава и др. Нелинейный характер совокупностей процессов, сопровождающих массоперенос, может приводить к появлению нескольких стационарных состояний, в которых мембрана обладает различными свойствами.


Найдены значения средней тепловой энергии электронов в потоках эмиссии с электрода в плазму и из плазмы на электрод для случаев большой и малой величины коэффициента кинетического отражения. Показано, что эти значения меняются в пределах 0,5 kBTc < << 2kBTc и 0,5 kBTe < < 2kBTe, соответственно (Tc и Te - температуры катода и электронов плазмы). Полученные значения могут использоваться при постановке граничных условий для гидродинамических уравнений на электроде или диэлектрической стенке.

Бауров А.Ю., Шибкова Л.В., Шибков В.М., Копыл П.В., Сурконт О.С. ВНЕШНЕЕ ГОРЕНИЕ ВЫСОКОСКОРОСТНЫХ МНОГОКОМПОНЕНТНЫХ ВОЗДУШНО-УГЛЕВОДОРОДНЫХ ПОТОКОВ В УСЛОВИЯХ НИЗКОТЕМПЕРАТУРНОЙ ПЛАЗМЫ // Вестник Московского университета. Серия 3: Физика. Астрономия. – 2013, № 4.- С. 28-33.

Экспериментально реализована стабилизация внешнего (на поверхности пластины) горения высокоскоростных многокомпонентных (воздух, спирт, пропан) потоков. Показано, что при сгорании спирта тепловые потоки возрастают приблизительно в 7 раз, а при горении пропана — в 15 раз по сравнению с тепловыми потоками от разряда, создаваемого в высокоскоростном воздушном потоке. Концентрация электронов, измеренная на расстоянии 10 см вниз по потоку от кончиков электродов, равна приблизительно 109 см?3 при создании разряда в потоке воздуха, тогда как при горении спирта достигает 2 • 1011 см?3 , а при горении пропана равна 3 • 1011 см?3 . Температура пламени в области существования разряда изменяется от 2000 до 2500 К, а вне разряда на расстоянии z = 20 см от электродов равна 1800 К, постепенно уменьшаясь вниз по потоку. Показано, что в условиях комбинированного разряда в дозвуковом потоке реализуется полное сгорание жидких и газообразных углеводородов. В условиях сверхзвуковых потоков полнота сгорания в зависимости от скорости потока достигает 95%.

Бедрина М.Е., Егоров Н.В., Клемешев В.А. МОДЕЛИРОВАНИЕ НАНОСТРУКТУР НА ВЫСОКОПРОИЗВОДИТЕЛЬНОМ ВЫЧИСЛИТЕЛЬНОМ КОМПЛЕКСЕ // Вестник Санкт-Петербургского университета. Серия 4: Физика. Химия. – 2010, № 4. - С. 136-140.

Появление на факультете ПМ-ПУ высокопроизводительного вычислительного комплекса позволило осуществить квантовомеханическое моделирование сложных систем и процессов, приближённых к реальности. Тем самым появилась возможность гораздо надёжнее прогнозировать свойства веществ. На сегодняшний день это является крайне актуальным в связи с необходимостью развития нанотехнологий. Вычислительная система состоит из одного управляющего узла, 48 специализированных вычислительных узлов и системы хранения данных ёмкостью около 8 Тб. Управляющий узел имеет 2 четырёхъядерных процессора “Intel Xeon 5335” (2 ГГц), 8 Гб оперативной памяти, RAID массив ёмкостью 3 Тб и 2 сетевые карты Gigabit Ethernet. Вычислительные узлы отличаются от управляющего тем, что имеют 4 Гб оперативной памяти, локальные жёсткие диски ёмкостью 160 Гб и сетевые интерфейсы Infiniband. В вычислительной системе используются 3 типа коммуникационных сетей: – Gigabit Ethernet для передачи данных, файлов и т. д.; – Infiniband для обмена данными программ под MPI; – RS-485 для сервисного обслуживания вычислительных узлов. За полтора года существования кластера проведены расчёты электронной структуры супермолекулярных систем, содержащих 500 и более атомов. Нам хотелось таким образом поставить задачи фундаментального исследования, чтобы они приблизились к проблемам прикладной науки и принесли практическую пользу. Методика расчётов. Все свойства изолированной молекулы и молекулярных систем (электронное строение, геометрические характеристики, энергетический спектр и т. д.) теоретически могут быть рассчитаны путём решения стационарного уравнения Шрёдингера: H?i _ _x1, _x2, . . . ,_xN, _R1, _R2, . . . , _RM _ = Ei?i _ _x1, _x2, . . . ,_xN, _R1, _R2, . . . , _RM _ , где ? – волновая функция системы, состоящей из N электронов и M ядер. Волновая функция i-го состояния системы ?i зависит от 3N пространственных координат {ri}, от N спинов электронов {si} и от 3M пространственных координат ядер {_RI}. В методе Хартри–Фока для многочастичной системы в адиабатическом и одноэлектронном приближениях решение уравнения сводится к решению системы интегродифференциальных уравнений методом самосогласованного поля. Помимо метода Хартри–Фока мы применяли хорошо зарекомендовавший себя метод функционала электронной плотности с использованием гибридных потенциалов PBE0 и B3LYP. В этом случае волновая функция зависела только от N переменных. Все расчёты проводились в рамках программного комплекса Gaussian 03 [1], установленного на кластере и приспособленного к параллельному режиму вычислений.

Богданова Ю.Г., Должикова В.Д., Цветкова Д.С., Карзов И.М., Алентьев А.Ю. КРАЕВЫЕ УГЛЫ СМАЧИВАНИЯ КАК ИНДИКАТОРЫ СТРУКТУРЫ ПОВЕРХНОСТЕЙ ПОЛИМЕРОВ // Журнал структурной химии. – 2011, № 6 (52). - С. 1224-1231.

Продемонстрированы возможности метода смачивания для характеристики структуры поверхностей полимеров и адсорбционных слоев поверхностно-активных веществ (ПАВ) на полимерных поверхностях, а также для определения энергетических характеристик полимерных поверхностей на различных границах раздела и использования этих величин для оптимизации выбора полимеров при решении конкретных практических задач.


Свойства электрических дуг, горящих в цилиндрических каналах плазмотронов (генераторов низкотемпературной плазмы), ещё полностью не изучены, поэтому в процессе исследования было промоделировано течение воздуха в областях тангенциальной подачи, в цилиндрическом канале, в сужающемся сопле или в смесительной камере плазмотронов и за их пределами (в окружающей среде). В итоге, было выполнено 3D-моделирование течения холодного плазмообразующего газа для исследуемых высоковольтных плазмотронов переменного тока со стержневыми электродами в цилиндрических каналах.

Валуева Т.А., Валуев И.Л., Обыденнова И.В., Валуев Л.И. ХИМИЧЕСКАЯ МОДИФИКАЦИЯ БЕЛКОВ “УМНЫМИ” ПОЛИМЕРАМИ // Биоорганическая химия. – 2010, № 6 (36). - С. 769-773.

Изучена модификация белкового ингибитора протеиназ, овомукоида из белка утиных яиц, поли.N,N. диэтилакриламидом, обладающим нижней критической температурой смешения (НКТС). В молекуле овомукоида модификации подвергались свободные аминогруппы остатков лизина и N.концевого остатка, что приводило к существенному снижению активности ингибитора по отношению к трипсину и небольшому ее уменьшению по отношению к химотрипсину. При нагревании раствора модифицированного белка выше НКТС наблюдали трансформацию антитриптических центров овомукоида в антихимотриптические. Показано, что это явление обусловлено гидрофобизацией остатков лизина, локализованных в реактивных центрах ингибитора, при сохранении структуры «петли связывания», в результате чего молекулы химотрипсина начинали взаимодействовать с этими остатками, принимая их за остаток гидрофобной аминокислоты антихимотриптического центра.

Волынский А.Л., Панчук Д.А., Садакбаева Ж.К., Большакова А.В., Ярышева Л.М., Бакеев Н.Ф. ОЦЕНКА ДЕФОРМАЦИОННО-ПРОЧНОСТНЫХ СВОЙСТВ ПОВЕРХНОСТНЫХ СЛОЕВ ПОЛИМЕРОВ, ОБРАБОТАННЫХ В ПЛАЗМЕ // Химия высоких энергий. – 2010, № 4 (44). - С. 369-374.

Проведена поверхностная обработка пленок полиэтилентерефталата (ПЭТФ) и поливинилхлорида(ПВХ) холодной плазмой в течение 1–15 мин. Обнаружено, что последующая деформация полученных пленок сопровождается особым видом поверхностного структурообразования, который ранее наблюдали для полимерных пленок с тонкими твердыми покрытиями. Показано, что в отличие от металлических покрытий, толщина модифицированного поверхностного слоя мало зависит от времени обработки полимера в плазме. Разработанный ранее анализ возникающих картин позволяет оценить деформационно-прочностные свойства нанесенных покрытий. Впервые показано, что разрывная прочность модифицированного слоя, возникающего при обработке ПЭТФ в плазме, составляет ~12.3 МПа, а его разрывное удлинение колеблется от 20 до 90%. Обсуждаются обнаруженные отличия в свойствах модифицированных плазмой поверхностных слоев полимера от изученных ранее свойств металлических покрытий.


На примере крупнотоннажного термопласта (линейного полиэтилена), содержащего добавки наноразмерного диоксида кремния, экспериментально показано, что термомеханическое и фотохимическое воздействие на полученные полимерные нанокомпозиты приводит к такому изменению молекулярной и надмолекулярной структуры полимера, при котором происходит увеличение прочности материалов при температуре, превышающей равновесную температуру плавления полиэтилена, и рост их теплостойкости.


Показана возможность использования механохимического, фотохимического и радиационно-химического воздействия на типичные термопласты (ПЭ, ПП) с высокодисперсными добавками неорганической природы для изменения структуры и повышения физико-механических характеристик композиционных материалов. Установлено, что действие указанных агрессивных факторов на полимеры, содержащие такие добавки, особенно в наноформе, открывает новые позитивные возможности направленного модифицирования структуры и свойств высокомолекулярных соединений.

Григорян Р.А., Григорян Л.А. РЕНТГЕНОГРАФИЧЕСКОЕ ИССЛЕДОВАНИЕ СЛОЖНЫХ ОКСИДОВ СОСТАВОВ ZN2 - X(TIAZRB)1 - ХFE2XO4 // Неорганические материалы. – 2011, № 3 (47). - С. 368-374.

Приведены результаты рентгенографических исследований сложных тугоплавких оксидов составов Zn2 – x(TiaZrb)1 – хFe2xO4, где (a + b = 1; a : b = 1 : 5, 1 : 4, 1 : 3, 1 : 2, 1 : 1, 2 : 1, 3 : 1, 4 : 1, x = 0–1.0; ?х = 0.05). Синтез образцов осуществлялся путем сплавления оксидов соответствующих металлов в низкотемпературной плазме водород!кислородного пламени. Идентифицированы две фазы с широкими областями гомогенности: ?!фаза со структурой обращенной кубической шпинели и ?!фаза со структурой обращенной тетрагональной шпинели. Установлены границы раздела фаз. Приведены кристаллографические параметры около 100 твердых растворов.

Дезорцев С.В., Доломатов М.Ю., Нигматуллина И.Е. ЗАВИСИМОСТЬ ДИНАМИЧЕСКОЙ ВЯЗКОСТИ ОТ СОСТАВА И ТЕМПЕРАТУРЫ В НЕФТЕПОЛИМЕРНЫХ СИСТЕМАХ // Башкирский химический журнал. – 2012, № 4 (19). - С. 24-28.

Реологические свойства нефтеполимерных систем при изменении состава имеют общие закономерности – подчиняются уравнению Френкеля для течения жидкостей. Для высокомолекулярных систем на основе термопластов и эластомеров на диаграмме зависимости динамической вязкости от концентрации полимеров наблюдаются три области, в которых состояние систем регулируется образованием гелеобразных структур. Применение известных представлений о природе вязкого течения, кинетической теории жидкостей и теории критических состояний к многокомпонентным системам типа «НДС–полимер» позволяет создавать материалы с заданными реологическими свойствами.

Ермаков А.Н., Мишарина И.В., Ермакова О.Н., Жиляев В.А., Зайнулин Ю.Г., Малашин С.И., Добринский Э.К. ОСОБЕННОСТИ ФАЗООБРАЗОВАНИЯ В СИСТЕМЕ TIN-NI ПОСЛЕ ПЛАЗМОХИМИЧЕСКОЙ ОБРАБОТКИ НИКЕЛИДА ТИТАНА И СПЕКАНИЯ ПОЛУЧЕННОЙ КОМПОЗИЦИИ // Материаловедение. – 2011, № 3. - С. 34-37.

Исследовано фазо- и структурообразование керметов TiN-Ni в ходе жидкофазного спекания нанокристаллического порошка, полученного методом плазменной переконденсации никелида титана в низкотемпературной азотной плазме. В результате исследования предложен механизм жидкофазного спекания, включающий формирование мелкодисперсных включений нитрида титана в никеле и сетчатого каркаса тугоплавкой основы.

Крисилова Е.В., Елисеева Т.В. АНАЛИЗ СТРУКТУРЫ ПОВЕРХНОСТИ ПЕРФТОРИРОВАННОЙ СУЛЬФОКАТИОНООБМЕННОЙ МЕМБРАНЫ В ВОДОРОДНОЙ И ЛИЗИНОВО// Сорбционные и хроматографические процессы (ВАК)(RUS). - 2010. - т. 10. - N 1. - с. 103-107.


Методом атомной силовой микроскопии исследована морфология поверхности ионообменной мембраны МФ-4СК в водородной и лизиновой формах. На поверхности мембраны визуализированы неровности различного масштаба, представляющие собой глобулы полимера и поры. При сорбции аминокислоты наблюдалось некоторое увеличение шероховатости поверхности мембраны, увеличилась доля мелких пор (d<50 нм) и уменьшилась доля крупных. Возможной причиной изменения структуры поверхности мембраны в аминокислотной форме является уменьшение влагосодержания. Полученные в режиме фазового контраста изображения позволили заключить, что на поверхности мембраны в аминокислотной форме присутствуют более крупные структурные единицы, чем в водородной форме.

Лужкова И.В., Ермаков А.Н., Григоров И.Г., Зайнулин Ю.Г., Добринский Э.К., Малашин С.И. ПЛАЗМОХИМИЧЕСКАЯ ПЕРЕРАБОТКА КАРБИДА И НИКЕЛИДА ТИТАНА В НИЗКОТЕМПЕРАТУРНОЙ АЗОТНОЙ ПЛАЗМЕ // Металлы. – 2013, № 1. - С. 15-18.

Плазменной переработкой механической смеси карбида TiC и никелида титана TiNi получены нанокристаллические порошки TiCN(TiN)—TiNi(Ni). Методами сканирующей электронной микроскопии, сопряженной с энергодисперсионным анализом, рентгенофазового анализа, сканирующей туннельной микроскопии получены данные по морфологии, топографии, фазовому и элементному составам порошковых продуктов. tc "Плазменной переработкой механической смеси карбида TiC и никелида титана TiNi получены нанокристаллические порошки TiCN(TiN)—TiNi(Ni). Методами сканирующей электронной микроскопии, сопряженной с энергодисперсионным анализом, рентгенофазового анализа, сканирующей туннельной микроскопии получены данные по морфологии, топографии, фазовому и элементному составам порошковых продуктов. " tc ""

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Методом ИК-спектроэллипсометрии проведено исследование воздействия низкотемпературной плазмы на поверхность ПТФЭ. Определена толщина модифицированного в плазме слоя, его оптические константы, а также изучено изменение шероховатости поверхности образца. Установлено, что толщина шероховатого слоя в результате обработки уменьшается от 380 + 19 нм до 353 + 16 нм, а толщина модифицированного слоя под шероховатым составляет 732 + 37 нм.

Новиков П.Л., Семенова О.И., Щукин В.Г., Шарафутдинов Р.Г. СТРУКТУРНЫЕ ОСОБЕННОСТИ И ПРОВОДИМОСТЬ ПЛЕНОК КРЕМНИЯ. МОДЕЛИРОВАНИЕ И ЭКСПЕРИМЕНТ // Журнал структурной химии. – 2012, № 4 (53). - С. 809-813.

Исследованы структурные и фотоэлектрические свойства низкотемпературных кремниевых микрокристаллических слоев, полученных новым методом электронно-пучковой плазмы, образующейся при воздействии электронного пучка на сверхзвуковой поток исходных газовых смесей. На основании экспериментов и выполненных методом Монте-Карло расчетов установлено, что зависимость проводимости слоев ?c-Si:H от степени кристалличности материала описывается в рамках теории перколяции.

Павлов Н.Н., Баранцев В.М., Дегтярев С.В., Дубанкова Н.П., Платова Т.Е., Михайлова О.В., Масленникова А.В. НОВОЕ В ФУНКЦИОНАЛИЗАЦИИ СИНТЕТИЧЕСКИХ ВОЛОКОН И МАТЕРИАЛОВ ИЗ НИХ С ПОМОЩЬЮ КОМПЛЕКСНЫХ СОЕДИНЕНИЙ МЕТАЛЛОВ // Известия высших учебных заведений. Серия: Химия и химическая технология. – 2010, № 12 (53). - С. 88-91.

На поверхности полимерных материалов получены металлоксидные высокодис- персные слои, свойства и структура которых существенно изменяют физико- химические характеристики волокнообразующих полимеров. Предложен возможный механизм образования поверхностных оксидных структур.


Исследованы структура, состав и электрокаталитические свойства покрытий, формируемых на алюминии ионно-ассистируемым осаждением (IBAD) платины из плазмы импульсного дугового разряда в режиме, при котором в качестве ассистирующих процессу осаждения используются ионы осаждаемого металла. Толщина исследуемых покрытий достигает ~30 nm; слоевое содержание атомов платины в покрытии составляет ~2.6• 1016 cm-2. Электрокаталитическая активность электродов на основе алюминия с осажденными покрытиями в реакциях электрохимического окисления метанола и этанола, лежащих в основе принципа действия низкотемпературных топливных элементов - перспективных химических источников тока, существенно превышает активность платинового электрода.


Определены особенности молекулярной структуры и морфологии тонких композиционных металл - полимерных и полимер - полимерных покрытий на основе полиэтилена, формируемых из активной газовой фазы и их изменения, протекающие при отжиге. Введение металлов вызывает снижение кристалличности формируемого полиэтиленового композиционного покрытия, изменяет соотношения ненасыщенных двойных связей. При отжиге таких покрытий образуются слоистые структуры. При нагреве нанокомпозиционных слоев ПЭ - ПТФЭ наблюдается снижение содержания двойных ненасыщенных связей и кристалличности полиэтиленовой компоненты, уменьшение числа дефектов во фторопластовой компоненте композиционного покрытия.

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Рычков А.А., Яблоков М.Ю., Кузнецов А.Е., Гильман А.Б., Кузнецов А.А. ЭЛЕКТРЕТНЫЕ СВОЙСТВА ПЛЕНОК СОПОЛИМЕРА ТЕТРФТОРЭТИЛЕНА С ГЕКСАФТОРПРОПИЛЕНОМ, МОДИФИЦИРОВАННЫХ В ТЛЕЮЩЕМ РАЗРЯДЕ // Химия высоких энергий. – 2010, № 4 (44). - С. 375-379.

Исследованы электретные свойства пленок сополимера тетрафторэтилена с гексафторпропиленом,модифицированных в разряде постоянного тока. Показано, что обработка помещенных на аноде пленок, несмотря на существенные изменения химической природы поверхности, незначительно влияет на релаксацию отрицательного гомозаряда. Однако при релаксации положительного гомозаряда полностью подавляется низкотемпературный релаксационный процесс, ответственный за нестабильность электретного состояния в исходной пленке. Одновременно из спектра поверхностных состояний исключаются глубокие ловушки, с которыми связаны высокотемпературные процессы релаксации в полимере.

Скрипникова Н.К., Сазонова Н.А. ОСОБЕННОСТИ НАНОСТРУКТУРИРОВАННОЙ МАТРИЧНОЙ МОДЕЛИ ЦЕМЕНТНОГО КЛИНКЕРА ПРИ ПЛАЗМОХИМИЧЕСКОМ СИНТЕЗЕ // Вестник Иркутского государственного технического университета. – 2013, № 8 (79). - С. 33-37.

Установлено, что в условиях низкотемпературной плазмы на основе некондиционного сырья с повышенным со- держанием MgO (12,43%) происходит образование цементного клинкера, в структуре которого присутствуют наноразмерные модифицированные минералы алита шириной 90–900 нм, длиной 500 нм–20 мкм и белита с размерами до 2 мкм и отсутствует свободный оксид магния. Структура является равномерно-зернистой. Рост минералов алита и белита приходится на ранние этапы термообработки, в последующем осуществляется их уменьшение. Полученный цемент обладает высокой активностью.

Старокадомский Д.Л., Телегеев И., Головань С.В. ВЛИЯНИЕ АЭРОСИЛА А-100 НА ПРОЧНОСТЬ, НАБУХАНИЕ И СТРУКТУРУ ЭПОКСИПОЛИМЕРА // Пластические массы. – 2010, № 7. - С. 35-40.

Установлено, что характер разрушения эпоксиполимера при сжатии может изменяться в зависимости от концентрации аэросила А-100, и проходит в явной или скрытой форме через две стадии. Как правило, с введением аэросила наблюдается заметный рост прочности на сдвиг на стеклопластиковой подложке (10-15%) и незначительный - на сжатие и микротвёрдость (3-6%). Это может объясняться изменением структуры композита с наполнением, что подтверждают кривые набухания в водной и кислых средах. Анализ СЭМ и АСМ-изображений показывает, что при наполнении в пористой матрице полимера формируется две фазы: наполнитель в полимере и полимер в наполнителе.



Экспериментально исследовано влияние 2 мас% нанокремнеземов (НК) с различной природой поверхности и микронаполнителей (рутила, полимерных порошков, опилок) на набухание в концентрированной азотной кислоте (к.HNO3) и структуру эпоксидного полимера. Выявлено, что с ростом удельной поверхности немодифицированных НК степень набухания снижается, что приводит к росту стойкости композита в к.HNO3. Использование алюмокремнеземов способно усилить стойкость к набуханию, тогда как микронаполнители и нанодисперсный TiO2 (анатаз) не дают эффекта. Усиления стойкости к действию к.HNO3 можно достичь подбором оптимальной концентрации НК и модифицированием его поверхности. В особенности эффективным является наполнение 5 мас% НК, модифицированного метакрилатсиланом А174. Согласно данным электронной микроскопии и рентгеноструктурного анализа установлено, что после наполнения силанизированными кремнеземами в структуре композита могут происходить изменения, связанные с появлением упорядоченных структурных зон.


Исследована взаимосвязь топологических характеристик химической и физической сеток адамантансодержащих эпоксидных полимеров ангидридного отверждения. Показано, что введение фрагментов адамантана в сетку эпоксидного полимера различными способами влияет на температуру стеклования и упруго-деформационные свойства. Изменение свойств полимеров в зависимости от концентрации модификаторов проанализировано при сравнении параметров частоты сетки химических связей и сетки зацеплений в рамках кластерной модели структуры аморфного состояния полимеров.



Исследованы эффекты структурной модификации эпоксидных полимеров (ЭП) моно- и дикарбоновыми кислотами адамантана. В рамках кластерной модели структуры аморфных полимеров выполнена идентификация составляющих рентгеновского аморфного гало исследованных объектов, основанная на предположении существования в них рыхлоупакованной матрицы и областей локального порядка. Установлено, что введение каркасных фрагментов адамантана увеличивает неоднородность структуры ЭП, что обуславливает изменение молекулярных и топологических характеристик.

Толстопятов Е.М., Гракович П.Н., Рахманов С.К., Васильков А.Ю., Никитин Л.Н. ОБРАЗОВАНИЕ УЛЬТРАДИСПЕРСНЫХ МИКРОАГРЕГАТОВ ПРИ ЛАЗЕРНОЙ АБЛЯЦИИ ПОЛИМЕРОВ // Перспективные материалы. – 2012, № 1. - С. 77-86.

С использованием закономерностей газодинамики и течения вязких жидкостей рассмотрены экспериментальные результаты по абляции полимеров лазерным излучением. Показано, что существенную роль в абляции полимеров играют деструкционные и термохимические процессы модифицирования молекулярной структуры в процессе облучения, приводящие в одних случаях к снижению, а в других — к повышению вязкости расплава. Интенсивность лазерного излучения,оптические свойства и физико-химическое состояние поверхностного слоя полимера определяют характер и количественные параметры процесса образования и форму микроагрегатов в абляционном потоке. Основное внимание уделено политетрафторэтилену (ПТФЭ), способность образования микроагрегатной фракции которого может быть доведена до высоких значений, что позволяет использовать лазерную абляцию (ЛА) для получения волокнисто-пористого ПТФЭ с уникальными свойствами. Волокнисто-пористый ПТФЭ использован в производстве высокоэффективных фильтров, способных работать в условиях агрессивных сред и повышенных температур.

Шавшукова С.Ю., Вихарева И.Н., Удалова Е.А. ПРИМЕНЕНИЕ МИКРОВОЛНОВОГО ИЗЛУЧЕНИЯ В ХИМИИ ПОЛИМЕРОВ // Башкирский химический журнал. – 2010, № 2 (17). - С. 116-120.

Обобщены результаты применения микровол- нового излучения по трем направлениям химии и технологии полимеров: получение высокомо- лекулярных соединений, отверждение полиме- ров и модификации полимерных волокон.

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