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The aim of this work is to encapsulate a self-healing photo-polymerisable material for aerospace applications. To meet the technical requirements of space applications - low and high temperatures: -120 °C (dark side) to +250 °C (solar side); UV radiations: 200-400 nm; low pressure: 10(-4 )Pa - we chose trimethylolpropane triacrylate as healing agent. This monomer polymerises at 190 °C. To avoid its earlier thermal polymerisation, an inhibitor was added to the monomer/photo-initiator formulation. Moreover, among several microencapsulation techniques tested, we chose the sol-gel process to form silica microcapsules containing the self-healing formulation. These microcapsules were characterised by different analysis (scanning electron microscopy (SEM), thermo gravimetric analysis (TGA), Fourier transform infra-red spectroscopy (FTIR), etc.) and satisfied our requirements (size 1-30 μm, thermal stability >250 °C). After the microcapsules breakage, the generation of poly(TMPTA) film by radical photopolymerisation of the released TMPTA monomer was proved by disappearance of the IR peak at 1635 cm(-1) (assigned to TMPTA). The obtained film has a thermal stability above 300 °C.

The present paper was aimed at studying the possibility of zinc (Zn) removal from the wastewater discharged from zinc electroplating processes. In order to save industrial and environmental resources, the concentrated solution could be reused after electrodialysis process. A mini-electrodialysis system with three cylindrical compartments and different membranes containing various resins (Purolite A500 and Hypersol-Macronet MN500) was employed, which can be further applied for the treatment of synthetic effluent which contained zinc ions. The electrodialysis system was operated at constant voltage using different concentrations of synthetic solutions of zinc ions, without and with electrolyte recirculation for 1.5 h. The pH and conductivity of solutions were measured before and after the electrodialysis process occurs. Also the removal ratio (Rr) and mass flow (J) of zinc ions, energy consumption (EC) and current efficiency (CE) were determined. It was found that electrodialysis treatment generated a very low conductivity solution, enabling its reuse as rinse water. According to the obtained results when using a membrane pair with higher ion exchange capacity (IEC) the removal ratio is improved (over 80%). The physico-chemical, structural and mechanical properties of prepared membranes were registered, before and after electrodialysis process takes place, by means of complementary analytical techniques, namely, ion-exchange capacity, water content and thickness measurements. Furthermore analysis were also carried out by Fourier transform infrared spectroscopy (FT-IR), environmental scanning electron microscopy (ESEM), thermal gravimetric analysis (TGA) and electrochemical impedance spectroscopy (EIS).

A cationic functionalization was carried out on poly(ethylene terephtalate) (PET) nonwovens by the method of padding with a solution of polymer (P1 and Px). An atmospheric pressure plasma treatment was prior used to improve the hydrophilic property of the nonwoven surface before the functionalization with cationic agents. The zeta potential measurements of the nonwovens, based on streaming potential, show the presence of cationic groups at the PET surface depending on the pH value. The analysis of washing water showed that the PET nonwoven functionalized with cationic polymer Px needed more washing cycles than with polymer P1, to remove all the species non fixed at the surface. The cytotoxicity tests show that both of ammonium polymers are toxic toward endothelial cells. This means that it leaves many active chemicals on the surface of the functionalized materials, even after washing. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

The sol–gel synthesis strategies combined with the templated growth of organic–inorganic hybrid networks provide access to an immense new area of innovative multi-functional advanced materials. One possible way to prepare such new advanced materials is to encapsulate liquid active agents (such as monomers, dyes, catalysts and hardeners) in microcapsules. Silica microcapsules of tetraethylortosilicate (TEOS) and 3-(trimethoxysilyl)propyl methacrylate (MPTS) were prepared in a precursor-monomer/NH4OH water microemulsion system. Trimethylolpropane triacrylate (TMPTA)—a trifunctional monomer useful in manufacturing of coatings, inks and adhesives—and a corresponding photoinitiator (DAROCUR 1173) were entrapped inside the obtained microcapsules. MPTS was used to increase compatibility between TMPTA and the sol–gel precursors. As stability agent we added a “home made” product resulted from functionalization of poly (ethylene glycol) methyl ether (MPEG) with (3-isocyanatopropyl) triethoxysilane (NCOTEOS). Were obtained microcapsules containing incorporated monomer and having average particle size in range of 0.5–50 μm. Thermal analysis, morphology study and the increase of the silica microcapsules average diameter, measured by DLS technique confirm the monomer encapsulation.

Free-radical copolymerization of cyclohexyl methacrylate (CHMA) and tetra (ethylene glycol) dimethacrylate (TtEGDMA) were carried out at 60 °C in tetrahydrofuran solution in presence of 2,2-azobisisobutyronitrile. The random copolymers were prepared with nominal crosslinking ratios, X of 1, 5 and 10% mol TtEGDMA / mol CHMA. The copolymers were characterized by 13C NMR spectroscopy. The copolymers was characterized by 13C RMN analysis and determined the copolymers composition. The monomer reactivity ratios r1 (TtEGDMA) and r2 (CHMA) were determined with the linearized copolymerization equations of the Fineman–Ross methods (r1 = 1.77 and r2 = 0.48) and Kelen–Tüdös (r1 = 1.81 and r2 = 0.46). Parameters of Alfrey-Price Q1 = - 1.10 (specific activity) and e1= - 0.64 (polarity) for TtEGDMA.

The classical techniques of PI film metallization by either vapour deposition or electrochemical reduction of metals involve necessary technological steps such as polymer surface modification via plasma or ion beam, electron beam, or photolytic treatment, or surface sensitization by the conferment of catalytic properties, in order to enhance metal- PI adhesion, which is the main problem to be overcome in all processes. The technology presented differs by the use of another chemical approach yielding electro-conductive materials with high reflectivity, but without damaging the films in the process. The metalized polyimide films have been prepared by heterogeneous chemical modification of the polyimide surface and the suggested technology includes several chemical conversion steps (hydrolysis, chelating by metal salts and reduction) requiring no complicated procedures and proceeding under mild conditions, at room temperature and without aggressive agents. This new process allows the formulation of metal phase while both simplifying the technology and making use of commercial PI films, such as Kapton®HN and Upilex®S. In memoriam of Dr. Saule K. Kudaikulova

β-Cyclodextrin ( 1 -CD) and 2 -cyclodextrin ( 2 -CD) (hosts) formed inclusion complexes with 4,41-bipyridinium dication derivatives with long chains (guests), in which the substituents on the bipyridinium nitrogen atoms are 1,3-bis(chloromethylphenethyl)-1,1,3,3-tetramethyldisiloxane. The number of 2 -CD molecules threaded onto the polymer chain increases with the length of the guest chain. In contrast, the number of β-CD molecules threaded onto the polymer is approximately 4 corresponding to each molecular chain, due to the repulsive interaction between β-CD and the quaternary bipyridinium units. The complexes were isolated in high yield and characterized by 1H NMR, 13C NMR, X-ray diffraction, thermal and scanning electron micrographs studies. As proven by X-ray analysis, the synthesized polyrotaxanes are crystalline materials with crystalline patterns significantly different from that of native cyclic oligosaccharide. The thermal stabilities of polyrotaxanes are higher than that of the physical mixture between cyclodextrin and the alternating copolymer, denoting the formation of the inclusion complexes. Scanning electron micrographs of polyrotaxanes reveal cubic and linear shapes without a well formed shape. Shape regularity and geometrical regularities in the agglomerating forms can be observed.

Epoxy-terminated polydimethylsiloxanes (E-PDMSs) of different molecular weight Mn were proved to undergo inclusion complexation into the inner cavity of β-cyclodextrin (β-CD), resulting in polyrotaxanes (PRots). The dethreading of the macrocycle was prevented by blocking the siloxane chain with a bulky substituent derived from 4-aminophenyltriphenyl methane (APhTPhM). As revealed by thermogravimetric analysis, differential scanning calorimetry, scanning electron microscopy (SEM), wide-angle X-ray diffraction and statistical analysis of SEM images, the thermal properties and the morphology of polyrotoxanes are dependent upon Mn, β-CD/E-PDMS molar ratio and the presence of free β-CD in the complexes.

The paper deals with the synthesis and physico-chemical characterization of polydimethylsiloxanes modified with piperazinyl ligand groups and of their Cu(II) complexes. 1H NMR, Fourier transform infrared, UV-VIS and electron spin resonance spectroscopy were used to follow the structure of the coordination compounds. Three different types of copper bonding to the macromolecular ligand were identified. An uniform distribution of Cu(II) cations into the polymeric material was evidenced by an environmental scanning electron microscopy/microanalysis by energy dispersive spectrometry combined method.

New polyurethane microcapsules incorporated with an antituberculous drug, isoniazid, have been synthesized through the interfacial polycondensation of tolylene 2,4-diisocyanate with different poly(ethylene glycols) in a water-toluene emulsion. As the poly(ethylene glycol) chain is elongated, the conversion of diiso- cyanate decreases with time; the content of urea groups in polyurethanes increases; and the morphology of cap- sule walls changes, with the walls becoming looser. At high poly(ethylene glycol) concentrations, the efficiency of isoniazid encapsulation decreases owing to displacement of the drug into the organic phase. An increase in the poly(ethylene glycol) concentration above 50 vol % leads to densification of polymer capsule walls because of enhancement of the diffusive accessibility of the monomer. As a result, the release of isoniazid decelerates almost twofold.

Polyfunctional aromatic imines with a zwitterionic character involving sulfonic acid and N,N-dimethylamino functionalities are synthesized by oxidative condensation of 5-aminonaphthalene-2-sulfonic acid (Cleve's β-acid) and N,N-dimethyl-p-phenylenediamine.

New acridine derivatives have been prepared via Ullman condensation involving benzoxazole (5) and 2-bromo-benzoic acid. Linear products were obtained. The structure of oxazolo[4,5-b]acridine was determined by NMR spectroscopy.

The chemical dehydrochlorination of polyvinyl chloride was studied in solution in tetrahydrofuran. The dehydrochlorinated products were characterized by their chlorine contents and by UV/visible spectroscopy. The absorption spectra of dehydrochlorinated PVC consist of a series of absorption maxima between 200 and 600 nm due to the formation of conjugated polyenic sequences. In this article we describe a new method for polyenic sequences evaluation based on deconvolution of the experimental spectrum. A comparison with the former technique usually employed is presented.

Self-standing and coated-on-glass films were prepared from polymer-inorganic ormosils, using the cationic polymer poly(methacrylamide propyl quaternarydimethyldodecyl bromide). The inorganic compound was grown in sol-gel reactions based on methyltriethoxysilane (MeTES), with or without addition of the titanium-precursor: tetraisopropyl orthotitanate. As evidenced by thermogravimetric analysis and differential scanning calorimetry data, the thermal properties of the films are highly dependent on the internal morphology. Inorganic granules with a TiO2 rich shell have a more polar surface, which stimulates stronger electrostatic interactions with the polymer, hence, a reduced mobility for the amino end and a smaller probability to have amino ends engaged in interactions at the surface of the granules. Coated-on-glass films drawn from pure cationic polymer suffer from partial dewetting. Topographic and force-versus-distance recordings using atomic force microscopy showed a change in the energy balance and no dewetting regions were encountered for polymer/MeTES based composites. However, because of nongrafted polymer, these films are not immune at washing with water/ acetone. Explorations of antibacterial activity against the gram-negative bacteria, Pseudomonas aeruginosa, were done using ormosil films with alkoxysilanes combinations.

Polyfunctional aromatic imines with a zwitterionic character involving sulfonic acid and N,N-dimethylamino functionalities are synthesized by oxidative condensation of 5-aminonaphthalene-2-sulfonic acid (Cleve's β-acid) and N,N-dimethyl- p-phenylenediamine.

The most common way to prevent biofouling of immersed surfaces is to coat the exposed surfaces with a paint containing a biocide acting on marine organisms by diffusion into the surrounding water. However diffusion of toxins into the marine environment causes pollution and serious economic problems. This paper outlines the anti-microfouling properties of some insolubilized quaternary ammonium salts (grafted onto a vinyl copolymer by means of a covalent non-hydrolyzable bond). After immersion times in sea-water up to 4 months, the microbial cover was limited to bacterial forms, without microalgae or cyanobacteria as observed on the untreated, or tin-salt painted surfaces. Bacteria are mostly on unicell forms and numerous areas appear free of any microorganisms. As microbiofouling is an obligate step to macrofouling, this unleachable antifouling treatment could result in a prolonged protection.