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In this work, silica microcapsules containing phosphonium ionic liquid (IL), denoted SiO 2 @IL, were successfully synthesized for the first time using the one step sol-gel method in IL/H 2 0 emulsion. The morphologies of the obtained micron-size microcapsules, including their diameter distribution, were characterized using dynamic light scattering (DLS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The thermal behavior of these microcapsules and the mass fraction of the encapsulated IL in the silica microcapsules were determined using thermogravimetric analysis, showing an excellent thermal stability (up to 220 °C) and highlighting that an amount of 20 wt.% of IL is contained in the silica microcapsules. In a second step, SiO 2 @IL microcapsules (1 wt.%) were dispersed into epoxy-amine networks to provide proof of concept of the ability of such microcapsules to act as healing agents as microcracks propagate into the epoxy networks., Competing Interests: The authors declare no conflicts of interest.

Thermo-reversible Diels-Alder (DA) bonds formed between maleimide and furan groups have been used to generate an interphase between carbon fiber surface and an epoxy matrix leading to the ability of interfacial self-healing in carbon:epoxy composite materials. The maleimide groups were grafted on an untreated T700 carbon fiber from a three step surface treatment: (i) nitric acid oxidization, (ii) tetraethylenepentamine amination, and (iii) bismaleimide grafting. The furan groups were introduced in the reactive epoxy system from furfuryl glycidyl ether. The interface between untreated carbon fiber and epoxy matrix was considered as a reference. The interfacial shear strength (IFSS) was evaluated by single fiber micro-debonding test. The debonding force was shown to have a linear dependence with embedded length. The highest healing efficiency calculated from the debonding force was found to be about 82% more compared to the value for the reference interface. All the interphases designed with reversible DA bonds have a repeatable self-healing ability. As after the fourth healing, they can recover a relatively high healing efficiency (58% for the interphase formed by T700-BMI which is oxidized for 60 min during the first treatment step)., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Hydrogen bond mediated films made by step by step deposition of poly(4-vinylpyridine) (P4VP) and hydroxylated poly(2,3,4,5,6-pentafluorostyrene) (PPFS) copolymers prepared by thiol para-fluoro coupling, bearing either one (PPFSME) or two (PPFSMPD) hydrogenated hydroxyl groups or a (poly)fluorinated hydroxyl (PPFSOH), respectively, were successfully constructed. The influence of the structural parameters, such as the hydroxyl environment (which dictates the H-bond strength) was in-depth investigated in terms of their impact on (i) growth mechanism, (ii) internal organization, and (iii) surface features. The use of the weaker H-bond donor partner (PPFSME) leads to low quality films composed of irregularly distributed aggregates. While [PPFSMPD/P4VP] multilayer films are comparatively thick and composed of stratified layers with smooth topology, the use of PPFSOH with P4VP yields thin films made of mixed and interpenetrated polymer layers. Playing on the interaction strength appears as a powerful tool to elaborate tailored multilayer films with molecularly tunable properties.

The microstructure, thermal stability, surface energy, and swelling characteristics of two kinds of commercial organoclays, before and after washing treatment with a mixture of H2O/ethanol, were investigated using X-ray diffraction (XRD), thermogravimetric analysis (TG/DTG), wettability measurement, and swelling measurement. This study demonstrates that the external-surface physically adsorbed surfactant can be removed after washing treatment, resulting in an increase in thermal stability and a decrease in surface energy of the resultant organoclays. Organoclays are difficult to be introduced into a solvent when their surface energies are lower than that of the solvent. On the other hand, the organoclay with gamma(organoclay) < gamma(solvent) is easier to be swollen and expandable by the solvent. The swelling and basal spacing measurements of the organoclays introduced into organic media indicate that the swelling factor and the interlayer swelling are two independent parameters. Both the polar character of the solvent and the swelling capacity of clay have a prominent effect on the interlayer swelling of the organoclays.

The grafting reaction between a trifunctional silylating agent and two kinds of 2:1 type layered silicates was studied using FTIR, XRD, TGA, and 29Si CP/MAS NMR. XRD patterns clearly indicate the introduction of 3-aminopropyltriethoxysilane (gamma-APS) into the clay interlayer. In the natural montmorillonite, gamma-APS adopts a parallel-bilayer arrangement, while it adopts a parallel-monolayer arrangement in the synthetic fluorohectorite. These different silane arrangements have a prominent effect on the mechanism of the condensation reaction within the clay gallery. In natural montmorillonite, the parallel-bilayer arrangement of gamma-APS results in bidentate (T2) and tridendate (T3) molecular environments, while the parallel-monolayer arrangement leads to monodentate (T1), as indicated by 29Si CP/MAS NMR spectra. This study demonstrates that the silylation reaction and the interlayer microstructure of the grafting products strongly depend on the original clay materials.

This study aims to determine the relevant parameters controlling the organophilic montmorillonite dispersion in various organic solvents which can be used as dispersion media for polymer coatings. These suspensions were studied at three scales: At nanometer scale by looking to interlayer distance: When the solvent surface energy is higher than the organophilic clay surface energy, i.e., gamma solvent > or = gamma montmorillonite, the intercalated organic chains of the quaternary ammonium modifier swell, leading to an increase of the interlayer distance. The balance between hydrophilic and hydrophobic character is the key to dispersion of nanoclays. At micrometer scale by studying the rheological behaviour of clay suspensions: Gels are formed by percolation of microgels, based on swollen 3-4 platelet tactoids. The viscoelastic properties and the flow behavior reveal the gel structuration by measuring the gel stiffness and the flowing stress. At macroscopic scale analyzed from the swelling of the nanoclay into solvents: The compatibility between solvent and organophilic clay governs the macroscopic swelling, i.e., interactions between organic chains borne by the intercalated ions and solvents govern the final suspension morphologies. The same methodology can be adopted for monomers or prepolymers selected for one in situ intercalation/exfoliation processing route.

14 cases of idiopathic rapidly progressive glomerulonephritis (I. R. P. G. N.) treated by heparin between 1968 and 1974 were collected by the authors. Extra-capillary crescents (E. C. C.) occurred in 75 to 100% of glomeruli in ten patients and in 50 to 75% in four. Gross proteinuria, hematuria and renal failure were always present. 9 patients were admitted with primary oligo-anuric renal failure. 11 patients were treated by repeated hemodialysis before and during anticoagulant treatment. Heparin was given by intra-venous injection every 3 hours for one to two months with Howell times range from 150 to 200% of control. Heparin was the only treatment in 6 cases, and was given with dipyridamole in 4, with prednisone in 3 and with azathioprine in one case. 5 severe or fatal hemorragic complications were observed. The clinical course was usually unfavorable with 5 early deaths, 3 provisional steady-states with 2 late deaths. Six patients were treated by periodic hemodialysis. Repeat kidney biopsies were obtained in 8 patients. The findings suggest that heparin affects mainly the E. C. C. and fibrinoid deposits but not glomerular sclerosis. The inefficiency of all current treatments of primary oligo-anuric IRPGN is stressed. In patients with better initial renal function choice between anticoagulant and/or immuno-depressive drugs must be scrutinized in individual cases bearing in mind potential iatrogenic complications. In equivocal cases, patients should be referred to the chronic hemodialysis and/or transplantation program.