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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.

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.

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.

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.

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.

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.

Novel interpenetrated polymer network type microparticles of gelatin and poly(vinyl alcohol) (PVA) were prepared by reverse-emulsion crosslinking method using glutaraldehyde (GA) as crosslinking agent. Microparticles morphology, particle size, swelling behaviour and drug loading/release are discussed in respect to the preparation parameters such as the influence of the polymer concentration in the aqueous phase, pH of the aqueous phase, ratio between the total amount of polymers and the amount of crosslinking agent and the ratio between Gel and PVA in initial aqueous solution (w/w). Chloramphenicol (CLF), a model hydrosoluble drug, was successfully loaded into these microspheres.