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In this work, we report on the thermal and thermomechanical properties of rigid PU foams modified with POSS moieties, paying special attention to molecular dynamics of these systems. 1,2-Propanediolisobutyl POSS (PHI-POSS) are used as pendent groups and octa(3-hydroxy-3-methylbutyldimethylsiloxy) POSS (OCTA-POSS) serve as chemical crosslinks. DSC reveals an initial slowing down of the segmental dynamics for small loadings (5 wt%) of both POSS moieties, followed by an acceleration, probably due to changes in the topology of the PU network and the morphology of the foam. A low-temperature mechanical relaxation is observed by DMA and is attributed tentatively to a local β relaxation, much similar to that observed in hyperbranched polyurethanes. [ABSTRACT FROM AUTHOR]

This work reports the synthesis of rigid polyurethane (PU) foams modified by disilanolisobutyl polyhedral oligomeric silsesquioxane (DSIPOSS). This open‐cage nanostructure silsesquioxane has 2 hydroxyl groups and therefore can be chemically built directly in the PU backbone to form hybrid polyurethane‐POSS foam. Synthesis procedure using polymeric 4,4′‐diphenylmethane diisocyanate, polyetherol, and DSIPOSS has been elaborated, and the influence of POSS on the cell structure, closed cell content, apparent density, thermal conductivity, and compression strength of the rigid polyurethane composites has been evaluated. The hybrid composite foams containing 1.5 and 2.0 wt% DSIPOSS showed a reduced number of cells and an increased average area of foam cells in comparison with the unmodified PU, while the addition of 0.5wt% of DSIPOSS causes an increase in the number of cells of the foam as compared with the reference and thus a reduction in the average area of cells. X‐ray microtomography provided data on the porous structure of polyurethane hybrid materials, including reduction of the pore surface area. Scanning electron microscopy and energy‐dispersive X‐ray spectroscopy analysis revealed a good homogenization of DSIPOSS in polyurethane matrix. Thermogravimetric analysis results have shown that incorporation of POSS nanoparticles into PU foam does not significantly change the degradation process. The compressive strength of PUF‐POSS hybrids in the direction parallel and perpendicular to the direction of foam rise is greater than the strength of the reference foam already for the lowest DSIPOSS content. [ABSTRACT FROM AUTHOR]

This work reports on the preparation of polyurethane foams (PUFs) chemically modified by functionalized 1,2-propanediolisobutyl polyhedral oligosilsesquioxane (PHI-POSS) as pendant groups and octa(3-hydroxy-3-methylbutyldimethylsiloxy) POSS (OCTA-POSS) as chemical crosslinks. The resulting foams, which contain 0 to 15 wt% POSS (versus polyol), were characterized in terms of their structure, morphology, density, thermal conductivity, compressive strength, and water absorption. Fourier transform infrared-attenuated total reflectance revealed good reaction rate between POSS and PUF. PHI-POSS suppresses the formation of the hydrogen bonds in the soft phase. The composite foams with OCTA-POSS showed a reduced number of cells and increased average area of foam cells in comparison with the PUF, while the addition of PHI-POSS causes an increase in the number of cells of the foam as compared with the reference, and thus a reduction in the average area of cells. Scanning electron microscopy-energy-dispersive X-ray spectroscopy analysis revealed that POSS moieties form lamellae-shaped crystals of different sizes, distributed homogeneously in the bulk (PHI-POSS) or close to the self surfaces (OCTA-POSS). The compressive strength of PUF/POSS hybrids in the direction parallel and perpendicular to the direction of foam rise is greater than the strength of the reference foam. PHI-POSS improves monotonically the compressive strength in the studied loading range. About 5 wt% OCTA-POSS also provides reinforcement, but further loading reverses the phenomenon. PUF/POSS hybrids absorb less water than the pristine foam because of an increase of foam density. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A new material-epoxy resin (R) with added glycydyl derivative - 9-(2, 3-epoxypropyl)carbazole (EPK) was studied. RxEPK (x- wt. of EPK) emits light in the range from 330 nm to 470 nm. To obtain the best luminescence properties we analyzed the influence of various factors including different solvents used during preparation, different concentration of carbazole group and curing agent. The dependence of the absorption and photoluminescence (PL) spectra of RxEPK on these factors was determined. The best PL efficiency was obtained for x = 5% in fully crosslinked polymer. [ABSTRACT FROM AUTHOR]

Organic materials containing carbazole moiety are promising photonic materials for numerous applications including holographic storage, real-time optical processing, imaging, non-destructive testing and phase conjugation. The purpose of our research is the synthesis of functionalised polymers and copolymers of carbazole based derivatives containing p-nitrophenyl diazene moiety and study their optical response in thin film matrices. Some qualitative results concerning their potential in photorefractivity are reported. [ABSTRACT FROM AUTHOR]

Novel acrylate copolymer with carbazole pendant groups and derivatives of bipyridine as side chains were synthesized, in which derivatives of bipyridine as electro-optic chromophores and carbazolyl as photoconductive moiety were covalently linked to the acrylate backbone. 2-(9-Carbazolyl)ethyl methacrylate (CEM) and 2-methylacrylic acid 2-{4,4'-dimethyl-5'-[2-(5-methyl-thiophen-2-yl)-vinyl]- [2,2']bipyridinyl-5-yl}-ethyl ester (BiPy) were synthesized and then copolymerized to give (99:1), (98:2), and (92:8 mol/mol) CEM/BiPy copolymers. Solutions of the copolymers in dioxane were examined for their photoluminescence properties. [ABSTRACT FROM AUTHOR]

A study of polyaniline (PANI) doping with various cobalt compounds, that is, cobalt(II) chloride, cobalt(II) acetate, and cobalt(II) salen, is presented. The catalysts were prepared by depositing cobalt compounds onto the polymer surface. PANI powders containing cobalt ionswere obtained by one- or two-stepmethod suspending PANI in the following acetonitrile/acetic acid solution or acetonitrile and then acetic acid solution. Moreover different ratios of Co(II) : PANI were studied. Catalysts obtained with both methods and at all ratios were investigated using various techniques includingAAS and XPS spectroscopy.The optimum conditions for preparation of PANI/Co catalysts were established. Catalytic activity of polyaniline cobalt(II) supported catalysts was tested in dec-1-ene epoxidation with molecular oxygen at room temperature. The relationship between the amount of cobalt species, measured with both AAS and XPS techniques, and the activity of PANI-Co catalysts has been established. [ABSTRACT FROM AUTHOR]

Refractive index dispersion of thin films of deoxyribonucleic acid (DNA)-surfactant (CTMA) and doped DNA-CTMA-Nile Blue (NB) (5 w%) complexes are reported and discussed. The thermal variation of the thin film thickness was measured by ellipsometry. The DNA-CTMA complex exhibits a rarely observed negative thermal expansion between room temperature and ca. 85°C. Doping with NB decreases the temperature range of negative thermal expansion to between room temperature and ca. 70°C. The dopping by 5 w% of NB lowers the absolute value of negative thermal expansion of DNA-CTMA system from 5% to 2% within this temperature range. [ABSTRACT FROM PUBLISHER]

The article describes a modified method of polyaniline synthesis. The classical oxidizer-aqueous solution of hydrogen peroxide was replaced by different solid state hydrogen peroxide complexes, what helped keep constant temperature of the reaction mixture. The highest yield of the polymerization was obtained using urea-hydrogen peroxide. [ABSTRACT FROM AUTHOR]

Aspartic acid/lactic acid copolymers were synthesized under microwave radiation, without a catalyst, by bulk and solution method. The reaction was carried out also in the presence of phosphoric acid as the catalyst and with the use of a conventional heating. Furthermore, partial degradation of the copolymers by hydrolysis in a physiological NaCl solution and in the Lactated Ringer's solution was investigated. The structure of the products was characterized by Fourier-transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (1H NMR). Thermalproperties of the aspartic acid/lactic acid copolymers were determined by thermogravimetry (TG) and differential scanning calorimetry (DSC), while their molecular weight was measured by gel permeation chromatography (GPC). [ABSTRACT FROM AUTHOR]

In the present work slow-release phosphorus fertilizers were prepared by formation of crosslinked acrylic acid networks, modified by poly(ethylene glycol). The effect of polymerization conditions on swelling capacity was investigated. The results showed that the swelling capacity was affected by concentration of the fertilizer and amount of poly(ethylene glycol). Morphological analysis (SEM) shows the large surface of the hydrogels matrix. Besides, relationship between the release profiles and swelling capacity was observed. The influence of PEG macrochains in the polymer networks on fertilizer ions migration from hydrogel matrix to water has been discussed. [ABSTRACT FROM AUTHOR]

The oxidation of organic compounds with carbon-carbon double bond with molecular oxygen under atmospheric pressure in the presence of new polyaniline supported catalyst 1 has been studied. This catalyst turned out to be efficient and selective for oxidation of some unsaturated organic compounds. Oxidation of alkenes, cycloalkenes and terpenes give corresponding epoxy derivatives, whereas organic compounds with carbon carbon double bond in benzylic position give ketones as a main product. [ABSTRACT FROM AUTHOR]

Azocarbazole dyes are organic molecules that have already shown potential in nonlinear optical applications in host-guest systems. These molecules should be covalently bound to a host polymer network. This can be easily achieved if the host polymer is an epoxy resin. The work reports synthesis and properties of four new azocarbazoles dyes bearing a hydroxy function, which enables binding to epoxy resin. [ABSTRACT FROM AUTHOR]

Introduction: The function of reconstructed bladder depends on the contracting bladder wall. This can be obtained with a proper innervating segment. Polyglycolic acid (PGA) is used as cell vehicle. Chitosan supported the adhesion and differentiation of neurons. The aim of the study was to compare PGA with PGA/chitosan ‘sandwich’ grafts for bladder regeneration. Methods: 3T3 fibroblasts were seeded on 6 PGA and on 3 chitosan scaffolds and incubated for 3 days at 37°C in 5% CO2 before implantation. Three rats underwent bladder reconstruction with PGA cell-seeded grafts and 3 with PGA grafts covered with chitosan cell-seeded grafts (‘sandwich’ graft). Three rats in the control group were not operated. After 6 months, reconstructed tissue was stained with hematoxylin and eosin. Neurons were identified by synaptophysin and neuron-specific enolase staining. Results: No complications were noticed. PGA/chitosan grafts were evaluated as (+++) and (++), while PGA grafts were evaluated as (++) and (+) with use of synaptophysin antibody. The control group was evaluated as (+). PGA/chitosan grafts were evaluated as (++) and (+), while PGA grafts were evaluated as (++) and (+) in neuron-specific enolase staining. The control group was evaluated as (+). Conclusion: Chitosan improved PGA’s abilities as a cell matrix and in guiding neurons into the graft. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

We report results of diffraction grating inscription on thin films prepared from epoxy resin doped with azo-carbazole based dyes. Diffraction gratings were recorded at the wavelength 532 nm and monitored through intensity of first order of diffraction (632 nm). Atomic force microscope scans of the gratings show that a surface relief grating also appeared. [ABSTRACT FROM AUTHOR]

A foreword to the April 2008 issue of "Molecular Crystals and Liquid Crystals" is presented.

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Results of investigations on novel formulations, structure-property relationships, curing, and compositions with fillers and reinforcing fibers (1997--2004) are reviewed with about 200 references to articles and several references to patents. The following topics are considered in particular: novel dibasic acids, glycols, crosslinking monomers, and curing systems, “vinyl ester” resins, fire retardant materials, IPNs and other systems comprising built-in thermoplastic polymers and oligomers with terminal functional groups. Information on unsaturated polyesters manufactured using PET scrap is given. Analytical (mainly spectrometric) methods for studying the chemical structure of crosslinked unsaturated polyester resins are presented. Approaches to the decrease in styrene emission on processing of unsaturated polyester resins are also discussed. [ABSTRACT FROM AUTHOR]

The oxidation of some arenes with the alkyl side groups by means of hydrogen peroxide is been presented. As the activator of hydrogen peroxide tungstoboric acid was chosen. The catalyst was examined under both homogeneous and heterogeneous conditions. The reactions under conventional conditions were compared with the microwave assisted reactions. [ABSTRACT FROM AUTHOR]

Fluorenone was nitrated using cupric nitrate in the presence of acetic acid and acetic anhydride. Nitration was carried out under mild conditions; 2-nitrofluorenone was obtained as the only product. [ABSTRACT FROM AUTHOR]