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Innovative well-defined acidic photopolymerizable phosphorus-based copolymers were prepared and tested in well-known dental applications to improve the adhesion of dental self-etch adhesives (SEAs). Thus, innovative diblock copolymers of dimethyl-(methacryloyloxy)ethyl phosphonate (DMAOyEP) and 2-hydroxyethyl methacrylate (HEMA) were first synthesized by RAFT polymerization using a dithioester chain transfer agent (CTA) and then modified. First blocks were prepared with good control over the molecular weights and low dispersities. They were then used as macro-chain transfer agents (macroCTAs) to control well the polymerization of a second block. Appropriate functionalization of the diblock copolymers was performed. First, the dithiobenzoate chain-end was removed, leading to the discoloration of the copolymers. Secondly, polymerizable groups were incorporated by a partial functionalization of the hydroxyl group of the HEMA moiety with 2-isocyanatoethyl methacrylate (IEMA). Finally, the acidic copolymers were obtained via the deprotection of phosphonated ester groups. Following this strategy, a range of copolymers was developed and compared, varying the percentage of polymerizable groups, block compositions, molecular weights and architecture. Even if the adhesion of dental self-etch adhesives (SEAs) is currently adequate, improvements are still welcomed, and these new phosphonic acid-based materials are an opportunity to develop new dental formulations. So, dental adhesive properties were evaluated with shear bond strength (SBS) experiments to highlight the best developed materials. This contribution shows the interest of employing appropriate polymerization techniques, and appropriate functionalization reactions to develop new materials that could improve the specific properties of dental formulations.

International audience; Lipidic polyols based on α‐hydroxyketone reactive groups were investigated for polyurethane thermosets. The reactivity of this peculiar secondary alcohol group in triacylglycerol structure was compared, without use of catalyst, to that of poly(1,2‐diol) triacylglycerol and castor oil to demonstrate the influence of ketone in the α position of the alcohol group in the presence of HDI for the urethanization rate. The kinetic effect of the ketone group was also studied on various lipidic architectures: mono(α‐hydroxyketone) ester, di(α‐hydroxyketone) diester and tri(α‐hydroxyketone) triacylglycerol. The presence of hydrogen bonds in the network coming from urethane, residual alcohol, and ketone in hard segments of PU was discussed and correlated with the thermal stability and the soft mechanical properties of the resulting polyurethane thermosets.

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International audience; Well‐defined linear alkyl benzene surfactants (COxn) were successfully synthesized using cardanol as a green phenolic alternative and initiator for polyoxazoline (POx), the hydrophilic block of nonionic surfactants. Various hydrophilic lipophilic balance values were investigated by varying the POx length according to the [monomer]/[initiator] ratio. The chemical structure of the surfactants, in particular the terminal groups, was well identified by matrix assisted laser desorption ionization time of flight mass spectrometry demonstrating the good progress of the cationic ring‐opening polymerization. The COxn surfactants spontaneously self‐assembled in water at a critical aggregation concentration of 1–2 µmol L−1 into nano‐objects characterized by a hydrodynamic diameter of 11–24 nm and a number of aggregations ranging from 30 to 60 according to the worm‐like micelle model.

International audience; Polymeric materials derived from fatty acids (FA)s were synthesized through free radical polymerization and evaluated as viscosity index improvers (VII) in an organic triglyceride lube oil (OTO). For this purpose, various FA-based copolymers were designed to own a reduced solubility at low temperature in OTO which can be gradually improved by increasing temperature. Different fatty amide methacrylates were chosen for their poorly oil-miscible repeating units while fatty ester methacrylates, 2-(methacryloyloxy)ethyl oleate (MAEO) and 2-(methacryloyloxy)ethyl 4-(dodecylthio)oleate (MAEOSC12), were used as oil-miscible comonomers for providing copolymers with a minimum of solubility in the lube oil. All copolymers were synthesized with a 50:50 M feed ratio and were fully characterized through 1H NMR, SEC, DSC, and TGA analyses. Then, rheological study of oil-copolymer blends revealed that copolymers containing –NH function were able to have a higher impact on oil viscosity at high than at low temperatures suggesting the coil copolymer expansion. This improvement of thickening power with temperature in OTO was further optimized by increasing the copolymer molecular weight, dispersity, concentration, pendant aliphatic chain length or by adding an additional aliphatic chain in the copolymer backbone. Moreover, copolymer additions in OTO did not disturb the initial Newtonian behavior of OTO at −30 °C which corresponds to the lube oil pour point.

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This work described the design of an efficient oleic‐acid based viscosity control additive for lubricating oils as potential alternative to petroleum poly(alkyl)methacrylates (PAMAs) additives. Hence, Poly(2‐(methacryloyloxy)ethyl oleate) (PMAEO) was synthesized by free radical homopolymerization to afford a comb‐like polymer structure similar to common PAMAs. Then, in order to evaluate its efficiency as viscosity control additive, the resulting polymer was mixed at several concentrations from 1%wt to 10%wt with different oil compositions, including a mineral paraffinic oil (MPO) and an organic triglyceride oil (OTO). For all polymer‐solution blends, relative viscosities (RV) measurements showed that addition of PMAEO in MPO had a better contribution on oil viscosity at 100°C than at 20°C (RV = 1.16 at 40°C while RV = 1.25 for 3%wt of PMAEO in MPO). These results were attributed to the coil expansion of polymer chains with increasing temperature. Additionally, rheological studies showed that addition of 3%wt of PMAEO in MPO improved the MPO cold flow properties at −30°C by decreasing the required yield stress to put the oil in motion from 310 mPa to 42 mPa. These results are in total accordance with the common viscosimetric properties of PAMAs‐based viscosity control additives at low and high temperature in mineral oils.

Background and objectives To assess lung ultrasound for the diagnosis and monitoring of respiratory complications in thoracic surgery. Methods Prospective observational study in a University hospital, single institution. Adult patients scheduled for pulmonary resection surgery excluding pneumonectomy. An ultrasound follow-up was performed from the day before the surgery to the third day after surgery with calculation of B-line and lung score (reaeration and loss of aeration scores). Respiratory complications were collected throughout the hospitalization period. Results Fifty-six patients were included. Eighteen patients presented a respiratory complication (32%), and they presented significantly higher BMI and ASA scores. Patients operated by videothoracoscopy were less at risk of complications. At day 3, a reaeration score ≤ 2 on the ventilated side or ≤ -2 on the operated side, and a B-line score > 6 on the operated side were in favor of a complication. Conclusion Lung ultrasound can help in the diagnosis of respiratory complications following pulmonary resection surgery.

International audience; Oligomers coming from glycerin carbonate acrylate (GCA) and solketal acrylate (SolA) were synthesized in good yields by free-radical chain transfer polymerization using 2-mercaptoethanol (ME) as chain transfer agent. These oligomers were totally soluble in solvents and did not exhibit branching or gelation. The efficiency of the chain transfer polymerization process on these glycerol-based acrylate monomers was demonstrated and reactive cotelomers bearing both acetal and cyclocarbonate groups were obtained. The structure of these oligomers was well-characterized by NMR, SEC, FTIR and MALDI-Tof spectroscopies. The oligo(GC-stat-Sol)s are particularly interesting, notably in terms of reactivity and solubility in various organic solvents and water that can be modulated by varying different SolA/GCA ratios. These results open the way to a widespread valorization of glycerol.

Photopolymerization is the subject of a growing interest both at industrial and academic levels because it provides high reaction kinetics, low emissions of volatile organic solvents and in some cases, low shrinking stress. This polymerization route has been largely developed using radical polymerization of vinyl monomers, but to a lesser extent by ring-opening polymerization (ROP). Beyond epoxides, which were the first monomers polymerized by a cationic ring-opening polymerization (CROP), the photopolymerization of other cyclic monomers has recently spread out thanks to the emergence of novel initiating systems. This review states an overview of the spectrum of cyclic monomers that have been polymerized by light-induced polymerization processes. In a first part, the photosensitive species able to trigger or to induce a change of kinetics of ROP reactions are presented according to their activation mechanism, i.e photouncaging, photoswitching or photoredox. In a subsequent part, the different monomer classes and their photopolymerization mechanisms are described with an emphasis on the properties of resulting materials. The last part covers the use of photoROP for several applications.

Vegetable oil-based microparticles were elaborated using environmentally friendly chemistry for pharmaceutical applications such as drug delivery systems. Castor oil (CO) was cross-linked by sol–gel chemistry to obtain a hybrid material offering original properties. CO functionalization was successfully achieved in the bulk with 3-isocyanatopropyltriethoxysilane (IPTES), then a simple and robust o/w emulsion process allowed both shaping functionalized oil into microparticles and favoring oil cross-linking. Several parameters were studied such as the stirring mode or the gelling agent for controlling microparticle characteristics. Spherical hybrid microparticles with a monodispersed size (around 300 μm) and a hybrid composition (13% w/w of mineral part) were characterized by size measurement, electronic microscopy, energy-dispersive X-ray spectroscopy, and thermal analysis. The effectiveness of the microparticles as potential drug delivery systems using ibuprofen as model molecule was demonstrated with a l...

International audience; Amphiphilic photo-induced triblock copolymers were successfully prepared by photodimerization of a photo-active initiator bearing coumarin moieties (CmTs2) before synthesizing, by cationic ring-opening polymerization (CROP), various lengths of polyoxazoline block. The DLS and TEM studies of the triblock copolymers self-assembly in water revealed that over 99% of the nanoparticles have a DH-value of 10 nm. The total photo-activity of the coumarin units permitted p-stacking interactions in the nanoparticle core and further its crystallization as demonstrated by DSC and X-ray diffractometry. An original nonspherical morphology of the nanoparticles resulted with an elongated shape.

International audience; The effects of polylactide-graft-cellulose nanocrystals on the thermal and mechanical properties of poly(l-lactide) matrices were investigated. Cellulose nanocrystals (CNCs) were grafted with polylactide chains via a solvent-free process by ring-opening polymerization of l-lactide using magnesium hydride as a catalyst. The efficiency of grafting was determined by infra-red, X-ray photoelectron spectroscopy and nuclear magnetic resonance analyses. X-ray diffraction analyses showed that the crystalline nature of the CNCs was preserved. Nanocomposites based on poly(l-lactide) matrix containing ungrafted nanocrystals (PLLA/CNCs) and grafted nanocrystals (PLLA/PLLA-g-CNCs) were investigated. DSC revealed that the grafted nanocrystals exhibited a strong influence on the crystallinity of the nanocomposites, inducing a significant enhancement of the mechanical properties of PLLA/PLLA-g-CNCs compared with PLLA/CNCs material. The role played by the polylactide grafted layer on the interaction between the CNCs and PLLA matrix was revealed by mechanical analyses in the solid and molten states.

The use of functional polymers for the sorption of metallic species in water was widely practiced in treatment processes. Such sorbents offered the possibility to remove a large range of metals because of the variety of possible functional groups on polymeric backbones. In particular, acidic groups (carboxylic, phosphonic or sulfonic groups) proved to be of great interest for the sorption of different cations. Sorption efficiency and selectivity through complexation or ion exchange interactions were directly linked to the nature of both the functional groups and the cationic metallic ions. In addition, the physical nature of materials was another important parameter that had to be considered. Depending on the polymer solubility, the cross-linking density, and the polymeric architecture, significant differences regarding sorption properties were observed in the sorption kinetics. Thus, it was challenging to select the appropriate polymeric sorbent with the most relevant physical nature and functionality in the area of wastewater treatment. This review aims at reporting organic polymeric materials bearing acidic groups able to interact (selectively or not) with metallic cations. Both synthetic and bio-based materials were reviewed and main parameters that had to be considered when choosing functional organic sorbents for the removal of metallic pollution were highlighted. Finally, recyclability of the polymeric sorbents was also considered.

An iodine modified polypropylene surface was synthesized by iodine plasma activation. The obtained polypropylene surface was found to be a useful platform for secondary reactions. For instance, an azide-functionalized PP was prepared by nucleophilic exchange reaction. The surface was proven to be reactive toward R group of an alkyne modified RAFT agent via the copper-catalyzed azide–alkyne cycloaddition. RAFT mediated graft polymerization of methacrylic acid was carried out and lead to a controlled polymerization from the surface. Characterizations of the modified surface and the grafted polymers were performed through FTIR-GATR, XPS, AFM and colorimetric assays.

Vegetable oil based hybrid films were developed thanks to a novel solvent- and heating-free method at the air-water interface using silylated castor oil cross-linked via a sol-gel reaction. To understand the mechanism of the hybrid film formation, the reaction kinetics was studied in detail by using complementary techniques: rheology, thermogravimetric analysis, and infrared spectroscopy. The mechanical properties of the final films were investigated using nano-indentation, whereas their structure was studied using a combination of wide-angle X-ray scattering, electron diffraction, and atomic force microscopy. We found that solid and transparent films form in 24 hours and, by changing the silica precursor to castor oil ratio, their mechanical properties are tunable in the MPa-range by about a factor of twenty. In addition to that, a possible optimization of the cross-linking reaction with different catalysts was explored, and finally cytotoxicity tests were performed on fibroblasts proving the absence of film toxicity. The results of this work pave the way to a straightforward synthesis of castor-oil films with tunable mechanical properties: hybrid films cross-linked at the air-water interface combine an easy and cheap spreading protocol with the features of their thermal history optimized for possible future micro/nano drug loading, thus representing excellent candidates for the replacement of non-environmentally friendly petroleum-based materials.

A series of amphiphilic photo-responsive heterografted copolymers have been successfully synthesized. The random copolymers were composed of a methacrylate backbone, with various compositions of hydrophilic oligomeric 2-methyl-2-oxazoline side chains (OMOx) and hydrophobic long alkyl chains terminated by a coumarin moiety (Cm). Using dynamic (DLS) and static light scattering (SLS), and transmission electron microscopy (TEM), their self-assembling behavior was studied in water using the nanoprecipitation method. Depending on the system, one, two or three particle size distributions co-exist in solution. However, DLS measurements showed that monomodal and slightly polydisperse self-assemblies were obtained with the more hydrophobic copolymers (i.e., 85% of hydrophobic monomers with a long alkyl chain terminated by a coumarin moiety (MCm) per molecule) with hydrodynamic diameters ranging from ca. 130 to 300 nm. Morphological information on these self-assembly structures was obtained using SLS: a Gaussian behavior has thus been evidenced. Finally, these heterografted copolymers were illuminated using UV light at λ = 350 nm inducing photo-crosslinking of the coumarin units. The influence of UV illumination on the thus-formed nanoparticles was investigated by carrying out complementarily DLS-measurements and UV spectroscopy.

To encapsulate and deliver poorly water-soluble drugs, castor oil/silica hybrid microparticles (HMP)s were synthesized. Green chemistries were used to silylate the oil and further cross-link it into solid microparticles by sol-gel reaction. Silylated castor oils (ICO)s at various silylation ratios were prepared and allowed the solubilization of ibuprofen at several concentrations up to 16 wt%. The HMPs were formulated by ThermoStabilized Emulsion (TSE) process which permits to “freeze” the oil-in-water emulsion while the sol-gel reaction occurs. The hybrid mineral/organic composition and the morphology (spherical shape and micrometric size) of these HMPs were determined by complementary technics (SEM, TGA, EDX, 29Si NMR and FTIR spectroscopies). The HMPs reached a good ibuprofen loading efficiency regardless to the formulation used while the release kinetics in simulated oral administration exhibited a tunable release during 3 h according to the silylation ratio. The ibuprofen rate also influenced its own amorphous or crystalline character within the HMPs. For subcutaneous conditions, ibuprofen release took place over 15 days. Finally, biodegradability assays in simulated digestion medium suggested a surface-limited hydrolysis of the particles and cytocompatibility studies on NIH-3T3 and Caco-2 cells demonstrated an excellent cellular viability.

Experimental conditions for the synthesis of poly(e-caprolatone)-graft-poly(vinyl alcohol) (PCL-g-PVA) and poly( l -lactide)-graft-poly(vinyl alcohol) (PLLA-g-PVA) via a PVA/MgH2 macroinitiator were optimized. Heat stability of PVA (99% hydrolyzed) in l -lactide (L-LA) melt was studied by DSC, TGA to lower the reaction temperature and time in order to avoid degradation. Thus, no degradation of copolymers occurred and 13C NMR study showed that l -lactide was incorporated in graft chains as isotactic poly( l -lactide) without racemisation for 140–160 °C, up to 25 h, L-LA/PVA ratio in the range 3–12. Such synthesis using non-toxic catalyst and reactants in a solvent-free medium can be described as environment-friendly. Amphiphilic behavior of copolymers was studied in aqueous solution according to their chemical structures: critical micelle concentration CMC (0.03–0.5 g L−1), average diameter of micelles (80–150 nm), surface tension γCMC (46–63 mN m−1), hydrophilic to lipophilic balance HLB (Griffin definition 4–7), and also from cast films: surface energy γs (36–50 mJ m−2). This environment-friendly process is suitable for the use of graft PVA copolymers in biomedical area for investigations under micelle applications.

International audience; The synthesis and the aggregation behavior of novel well-defined poly(N,N-diethylacrylamide)-b-poly- (L-lysine) (PDEAm-b-PLL) double hydrophilic block copolymers are reported. PDEAm-b-PLL was prepared using an original strategy which consisted of the ring opening polymerization (ROP) of N3- trifluoroacetyl-L-lysine N-carboxyanhydride using terminated-thiol PDEAm as a macroinitiator. After deprotection of the amine group of the L-lysine, pH- and thermo-sensitive poly(N,N-diethylacrylamide)- b-poly(L-lysine) block copolymers were obtained. The structure of the copolymers was characterized by 1H NMR and FT-IR. Then, pH and temperature sensitivities were measured by 1H NMR and UV/Vis spectroscopy. At different pH values and temperatures, poly(L-lysine) and poly(N,N-diethylacrylamide) showed typical behaviors, which led to different types of aggregation in aqueous solution. The influence of both stimuli was carefully investigated by DLS, TEM, and SANS.

International audience; Organomodified layered silicates and silicas have been incorporated in thermoplastic elastomers such as styrene-ethylene-butylene-styrene copolymers (SEBS) and polyurethanes (PU) in order to improve mechanical properties - especially tear strength. The organically modified layered silicates used were Cloisite (R) 30B, a montmorillonite modified with a ternary ammonium salt with hydroxyls as end groups and Nanofil (R) 2 which is organically modified by long chains of hydrocarbon and benzyl groups. Sepiolite, a natural clay with fibrous morphology was also used. The silicas incorporated are Aerosil 300, hydrophilic fumed silica and Aerosil R202, hydrophobic fumed silica. Nano-particles are incorporated between I and 5 weight percent. A compatibilizer SEBS grafted with maleic anhydride has been incorporated in some of the formulations for a better dispersion of some of the nano-particles. Different ways of incorporation have been investigated. For SEBS formulations, melt blends of SEBS pellets and clays have been prepared with an internal mixer and then films have been casted. For polyurethanes, solvent blending of polyols and clays were carried out in a vessel and then, compression molding of the blend with diisocyanates was made to synthesize polyurethanes. Materials have been compared on the basis of normalized tear test and sequenced tensile test. Mechanical parameters, as stabilization ratio (Mullins effect) and viscoelastic ratio, have been defined by integration of the stress-strain curves obtained. An interesting improvement of tear strength was observed for modified materials.

International audience; Polyurethanes cover a large range of materials exhibiting various physical and mechanical properties making them useful in different applications such as elastomers or biomaterials, for instance. The introduction of ionic groups in the polyurethane backbone opens the way to new applications where the ionic groups can act as physical crosslinkers that greatly modify the final mechanical and thermal properties of the materials. Furthermore, the hydrophilicity of the chains can be enhanced by the presence of the ionic species, and so the materials can be processed as conventional dispersions even in a polar solvent such as water. As a consequence the applications are numerous; the main commercial outlets are focused on coatings and textiles industries where they can be used as waterproof coatings or substitutes for leather. But these materials can also be used in high-tech industries for shape memory materials, biomedical devices and biocompatible materials. This review summarizes the latest developments of this class of promising materials and provides the reader with the potentialities of these polymers in various areas.

We report the synthesis by RAFT polymerization of well-defined diblock copolymers bearing carbamoylmethylphosphonate moieties which proved to sorb gadolinium. These poly(diethyl-6-(acrylamido)hexylcarbamoylmethylphosphonate-b-acrylic acid) (P(CPAAm6C-b-AA)) copolymers were able to self-assemble as a function of temperature, above their cloud point value.

Methyl methacrylate was copolymerized with propyl N,N-tetramethylbis(phosphonate)-bis(methylene)aminemethyl methacrylate (MAC3NP2). The thermal degradation and flammability of this modified poly(methyl methacrylate) (PMMA) were compared with those of pure PMMA using thermogravimetric analysis (TGA) and pyrolysis combustion flow calorimetry (PCFC). The morphology of char was investigated using scanning electron microscopy and the yield of phosphorus using energy-dispersive X-ray analysis. The gases evolved during degradation in TGA were analysed using Fourier transform infrared spectroscopy. The total heat release and heat release capacity of the reactively modified PMMA are reduced, as compared to pure PMMA. The modified PMMA presents a better thermal stability (above 290 °C) than pure PMMA and leads to an important char formation. A comparison among TGA, PCFC and the amount of phosphorus in the condensed phase gives useful information about the role of phosphorus in the flame retardancy of the copolymer. The result reveals the effect of phosphorus not only in the condensed phase but also in the vapour phase. Copyright © 2011 Society of Chemical Industry

A novel vegetable oil-based polyamine issued from grapeseed oil (GSO) was prepared using cysteamine chloride (CAHC) by thiol-ene coupling (TEC). The structure of the polyamine oil (AGSO) was carefully examined using a large range of chemical analyses (FTIR, 1H NMR and 13C NMR, LC-MS…). The effects of the amination of GSO on the vegetable oil properties were also studied using viscosimetry. Then, AGSO was employed as a novel curing agent for bio-based epoxy resin. The thermal crosslinking reaction between AGSO and epoxidized linseed oil (ELO) was studied by DSC and rheology. This study also dealt with the definition of the thermomechanical properties of the final material obtained by the mixing and curing of AGSO with ELO in stoichiometric proportions. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011

We report the cationic ring-opening polymerization of 2-methyl-2-oxazoline (MOx) using bio-based initiator (GCTs). The functional initiator GCTs was prepared by tosylation of the corresponding alcohol: glycerol carbonate (GC). The termination stage of the polymerization was achieved in presence of KOH and the telechelic polyoxazoline carrying five-membered cyclic carbonate and oxazolium end groups (GC-POxium) was converted to ((HO)2-POx-OH) carrying α-diol and ω-hydroxyl groups. End-functionalized polyoxazolines (HO)2-POx-OH with Mn ranging from 4200 to 8400 g mol−1 were synthesized. According to GPC results, the polymerizations of MOx using GCTs and other initiator coming from 1,2-isopropylidene-glycerol (Solk-Ts) were compared. On the basis of FTIR and NMR spectroscopies, the chemical modification of end chains of polyoxazolines was investigated by two alternative synthetic routes. The isocyanate route is a postpolymerization urethanization. The nucleophilic reactivity of the α-diol and ω-hydroxyl groups of (HO)2-POx-OH was studied with functional isocyanate (TESPI). In the carbonate route, the electrophilic reactivity of α- and ω-end groups of GC-POxium were explored with amine. It was demonstrated that during the termination stage of the polymerization in presence of allylamine both urethane linker in α-end chain was synthesized and the ω-oxazolium group was converted into terminal amine. The carbonate route is an alternative to synthesize urethane without isocyanate. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 4027–4035, 2010

International audience; The cationic ring-opening polymerization of 2-methyl-2-oxazoline (MOx) using iodine initiating system was reported. Uncolored polyoxazolines were produced in spite of the use of iodine initiator, well-known dye molecule. Low molecular weight asymmetric telechelic polyoxazolines carrying an acetylimine head group and an oxazolinium end group were synthesized, with a good control over the molecular weight. NMR and MALDI-Tof experiments allowed the full determination of the chemical structures of the produced poly(2-methyl-2-oxazoline)s, notably with the acetylimine head group, explained by spontaneous α-HI elimination. Finally, to our knowledge, we reported the first detailed mechanism of cationic ring-opening polymerization of 2-methyl-2-oxazoline in acetonitrile according to UV experiments. An ionic-type mechanism was involved with the dissociation of molecular iodine to active initiating species.

Peroxide-containing PDMS was synthesized according to a new pathway. Although hydrosilylation is one of the main reactions carried out in silicone chemistry, the catalysts used are very sensitive to the chemical nature of the reactants and remained inefficient to graft allylic peroxide. Radical catalyzed thiol-ene chemistry was involved for the first time to yield an initiator group containing polymer. The peroxide-grafted polysiloxane structure and decomposition were characterized using 1 H, 13 C and 29 Si NMR, FT-IR and Raman spectroscopies, SEC and DSC. These macroinitiators can be used to obtain polysiloxane able to undergo crosslinking.

International audience; The synthesis of amphiphilic lipid-polyoxazoline based on copolymers (CO-POxn) with narrow distribution has been achieved via cationic ring-opening polymerization of 2-methyl-2-oxazoline (MOx). Lipid-macroinitiator (COTs) was obtained from commercial castor oil (CO), widely renewable agricultural resource. CO-POxn with various length segments were synthesized from a macroinitiator COTs in order to investigate the effect of the length of the hydrophilic segment on the solution behavior of the nonionic polymer surfactants CO-POxn. The results showed that the critical micelle concentration rised with the increase of POx content and inversely surface tension decreased. The average size of aggregates of these structures suggested the formation of vesicles or nonspherical micelles. Star-shaped morphology of CO-POxn in solid state has also been observed using environmental scanning electron microscopy (ESEM). Addionally energy dispersive X-ray (EDX) analysis demonstrated the presence of POx block in the concentric stripes of the texture.

The free-radical cotelomerization of 3-(trimethoxysilyl)propyl methacrylate (TMSPMA) with 1,1,2,2-tetrahydroperfluorodecyl acrylate (PFDA) in the presence of 2-mercaptoethanol was performed at 80 °C in acetonitrile. Hydroxy end-groups of the cotelomers were reacted with 2-isocyanatoethyl methacrylate to give macromonomers. The P(TMSPMA-stat-PFDA) cotelomers, containing fluoro and silane groups, were then grafted onto silica nanoparticles. Optimal grafting conditions were found with TMSPMA monomer alone in toluene at 110 °C. The structure of the modified silica was analyzed by FTIR and 29 Si solid-state NMR. The amount of grafted TMSPMA or P(TMSPMA-stat-PFDA) was calculated by thermogravimetric and elemental analyzes. The grafting yield increased with the copolymer/silica weight ratio until a maximum value of 2.26 μmol/m 2 .

International audience; Novel organic/inorganic hybrid material was synthesized from poly(acrylazapropyl-trimethoxysilane)-b-poly( Ne-trifluoroacetyl-L-lysine) (P(AAPTMS)-b-P(TLL)) block copolymer using the sol–gel process. The treatment with ammonia solution permitted the hydrolysis of both trifluoro acetyl and trimethoxysilyl groups of the hydride copolymer followed by the condensation of the silanol groups, leading to crosslinked copolymers. The resulting cross-linked hybrid material was characterized using FT-IR, 29Si NMR, DSC, TGA, and environmental scanning electron microscopy. These techniques evidenced that a siloxane network was obtained. Amphiphilic polypeptide/inorganic hybrid copolymers were achieved and selforganized as particles in water.

10 pages; International audience; The telomerization of 3-(trimethoxysilyl)propyl methacrylate (TMSPMA) in the presence of 2-mercaptoethanol was investigated at 80 C in acetonitrile. In our case, the efficiency of 2-mercaptoethanol as telogen agent, with TMSPMA, was demonstrated and the transfer constant (CT) was determined. Moreover, cotelomerization of TMSPMA with perfluorodecylacrylate (PFDA) using various PFDA contents was investigated in order to obtain a-hydroxy oligomers with statistical copolymer-type main chains bearing trimethoxysilyl and perfluoro pendant chains. Until 10 mol% PFDA, no phase separation occured. In this composition, rTMSPMA and rPFDA reactivity ratios were calculated, thus showing a tendency for a statistical distribution of the monomer units in the copolymer.

International audience; A new method to prepare ionomers bearing terminal ionic groups has been developed by modification of different hydroxyl terminated oligomers and using vinyl phosphonic acid as reagent. The different oligomers have been characterized by NMR, MALDI-TOF, SAXS, SEM-EDX, thermal analysis and their ionic crosslinking was achieved using different cations. Characterization of the network was performed and proved that an efficacious crosslinking was reached depending on the nature of the cations.

International audience; Glycolysates coming from the chemical recycling of PET scraps are most often very crystalline compounds making them difficult to perform in further reactions like step growth polyaddition with diisocyanates to obtain polyurethanes. The glycolysis of PET was investigated using unusual reagents: polyesters based oligomers, bisphenol A, cycloaliphatic alcohol and aliphatic diols. The thermal properties of the glycolysates obtained were compared in terms of crystallinity with that of coming from the glycolysis with DEG. The crystallinity extents were calculated using X-ray diffraction. Surprisingly, the crystalline or non-crystalline nature of the reactants do not predict the morphology of the final glycolysates.

New phosphonated cross-linked polymers were synthesized from telomers obtained by reaction between 10-undecenol and dialkyl hydrogenphosphonates. Telomers were studied using MALDI-TOF MS. It was proven that side products were produced, corresponding to cross-esterification reactions of dialkyl hydrogenphosphonate on telomers and to radical additions of telomer on 10-undecenol. The same behavior was also observed with allyl alcohol. Telomers were then converted to resins by methacrylation reactions. Finally, photopolymerization of the different resins synthesized was achieved and influence of the nature of the phosphonate group (diester, monoacid and diacid) was also evaluated.

Valorization of poly(ethylene terephthalate) (PET) waste has been achieved using glycolysis. The resulting diols were employed for the synthesis of triblock copolymers by atom transfer radical polymerization using copper (I) bromide and (1,1,4,7,10,10)-hexamethyltriethylenetetramine as catalyst system. Macroinitiator was obtained after depolymerization of PET waste followed by functionalization of the obtained glycolysate with 2-bromoisobutyrate bromide. Polymerization of styrene (S) and glycidyl methacrylate (GMA) has been achieved leading to PS-b-PETG-b-PS and (PS-stat-PGMA)-b-PETG-b-(PS-stat-PGMA) triblock copolymers. Best results were obtained at 100 °C. At this temperature, termination reaction were negligible and the measured number-average molar mass of the product increased linearly with monomer conversion in agreement with the theoretical Mn with low polydispersity products achieved. Polymers were also characterized by 1H NMR. This work presents a original valorization of PET waste as (PS-stat-PGMA)-b-PETG-b-(PS-stat-PGMA) copolymer could be used as heat curable coatings. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 433–443, 2008

The synthesis of macromonomers of acrylic acid was performed by telo- merization in a three-step process. The first step was the telomerization of tert-butyl acrylate in the presence of thioglycolic acid. Different molecular weights were obtained with different ratios of the monomer to the transfer agent. Good control of the molecular weights and architectures of the oligomers (e.g., the presence of an acid function on the chain end) was observed. The transfer constant of tert-butyl acrylate with thioglycolic acid was assessed (chain-transfer constant ¼ 0.6). In the second step, the terminal unsaturation of the oligomers was obtained by the reaction of the terminal acid groups with 2-isocyanatoethyl methacrylate to yield the macromono- mers of tert-butyl acrylate. In the last step, the tert-butyl acrylate groups were hydro- lyzed in the presence of trifluoroacetic acid at room temperature. The macromono- mers were copolymerized with styrene to obtain graft copolymers, and the reactivity ratios were evaluated. Finally, the copolymers were characterized with surface elec- tron microscopy and atom force microscopy. V C 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 395-415, 2007

Mono- and di-(trimethylammonium)-terminated polystyrenes with similar molar masses were synthesized. Bromopolystyrenes were first prepared by atom transfer radical polymerization (ATRP) using (N-Boc-propylamino)-2-bromoisobutyrate as initiator and Cu(I)Br/2,2'-bipyridine as catalytic system in bulk at 110 °C. α,ω-Telechelic polymer with double molecular weight with respect to the starting polystyrene was then obtained under atom transfer radical coupling process using 2,2/-bipyridine and copper(0) mediated reductive conditions in anisole. Final (trimethylammonium)-terminated polystyrenes were eventually obtained after removal of the tert-butyloxycarbonyl group and permethylation reactions. Intermediate and final polymers were characterized by 1 H NMR. The aligning properties of the obtained polymers for liquid crystals have been investigated. Pretilt and zenithal anchorings on ITO/glass substrates were measured. Finally, the possibility for the telechelic polystyrene to form a network in an inverted microemulsion was also considered.

National audience; The synthesis and characterization of photopolymerizable unsaturated polyester resins based on PET waste are described. The resins came from a depolymerization process based on the glycolysis of PET by diethylene glycol (DEG). Different molecular weights of glycolysates were synthesized. Then, the latter was functionalized by a methyl hemiester of maleic acid to obtain unsatured ,-bismaleate PET oligomers. In the presence of an electron donor monomer, such as triethylene glycol divinyl ether, these electron acceptor oligomers were copolymerized by way of charge-transfer complexes under UV irradiation. The reaction was monitored in situ by real-time IR spectroscopy to study the kinetics of photopolymerization. This one was studied in relation with the physical and chemical characteristics of oligoesters and the composition of mixtures containing divinyl ethers. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1324-1335, 2007

International audience; The polymerization of methyl methacrylate (MMA) initiated by 2,2'-azobis(isobutyronitrile) (AIBN) as radical initiator in the presence of iodine (I2) was studied at different temperatures (T = 70 C and 80 C). This process, called reverse iodine transfer polymerization (RITP), is based on the direct reaction of radicals with molecular iodine. RITP efficiently controls the molecular weight (determined by size exclusion chromatography, SEC) and the structure of the polymer chains (confirmed by 1H and 13C NMR spectroscopy). For instance, PMMA samples of Mn,SEC = 2300 g mol-1 and polydispersity index PDI = Mw/Mn = 1.5 (Mn,theoretical = 2300 g mol-1), Mn,SEC = 4600 g mol-1 and PDI = 1.6 (Mn,theoretical = 4700 g mol-1), Mn,SEC = 9600 g mol-1 and PDI = 1.6 (Mn,theoretical = 10 000 g mol-1), and Mn,SEC = 19 200 g mol-1 and PDI = 1.5 (Mn,theoretical = 18400 g mol-1) were successfully prepared by RITP. The polymerization was followed by on-line 1H NMR spectroscopy, and the conversion of iodine was followed by titration with a thiol (thioglycolic acid). It was shown by SEC, titration of iodine, gas chromatography, and NMR analyses that RITP was split into two different periods: a first "inhibition" period during which iodine is consumed to form very short -iodotelomers, and a second period where the polymerization follows the kinetics of a conventional free radical polymerization governed by degenerative chain transfer. The degenerative chain transfer constant was estimated to be Cex 2.6 at T = 80 C. Last, the iodine-end-capped structure of the polymers was demonstrated by different analytical techniques, and the iodine functionality of the PMMA chains was up to 95%.

Hypothesis The interfacial compatibility between hydrophilic cellulose and hydrophobic poly( l -lactide) film surfaces is dependent on the interactions and interlocking of the macromolecular chains of the uppermost layers of both polymers. Grafting or coating the cellulose surface with molecular structures similar to the lactide monomer or oligomer is expected to improve the compatibility. Therefore, it should be possible to enhance the adhesive properties. Experiments Cellulose films were oxygen plasma treated and immersed in a l -lactide solution. The grafting was performed under various conditions (power, pressure, time). The treated cellulose and poly( l -lactide) films were hot-pressed, and the resulting bi-layer laminates were subjected to a peel test. Comparative experiments were performed with the bi-layer laminates prepared from the cellulose films coated with poly( l -lactide- graft -vinyl alcohol) copolymers. Findings X-ray photoelectron spectroscopy, infra-red analyses and wettability measurements revealed that chains bearing ester groups similar to that of lactide were covalently grafted onto the cellulose. The possible grafting mechanism that was initiated by the ionic species from the surface is discussed. As a result, the peel strength to separate the cellulose and the poly( l -lactide) films increased significantly. A comparison with data in the literature highlights the formation of entanglements inside the interfacial zone showing the efficiency of the plasma treatment.

Besides usual coupling agents such as, for instance, silane, thiol, or carboxylic acids, phosphonated-based low molecular weight molecules and polymers appear of great interest for the modification of metal oxides. In such contexts, this Review is focused on the use of phosphonated derivatives for the surface treatment of metal oxides as such compounds are known to establish strong and stable links with inorganic phases. Functionalization of metal oxides leads to the obtaining of hybrid materials that can find applications in numerous fields. As a result, an interesting prospect will be to enhance the development of new hybrid materials in the future, especially bio-based ones.

International audience; The glycolysis of PET by oligoester diols in the presence of zinc acetate was carried out in two successive twin-screw extruders with total residence times of 4 min and without solvent. These new glycolysates were analyzed and used in polyurethane formulation with a commercial polyol. The reactivity of these formulations was studied. The mechanical properties, thermal and swelling behavior of these polyurethanes were investigated. Mechanical properties are improved with the addition of glycolysate. The thermal e behavior is not modified with the addition of glycolysate. The swelling behavior of the material depends on the solvent nature. The addition of glycolysate allows a decrease in material swelling in chloroform but increases this swelling in acetone.

Different acrylate oligomers were synthesized by atom transfer radical polymerization in the presence of a transfer agent and CuBr/1,1,4,7,10,10-hexamethyltriethylenetetramine. The functionality in bromine was determined by 1H NMR. These oligomers were coupled in the presence of Cu(0) and the ligand 2,2′-bipyridine. The coupling yield was determined by size exclusion chromatography and NMR analysis and depended on the nature of the monomer and not on the molecular weight. In other words, the preliminary functionalization of the brominated chain end with styrene increased the coupling yield. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2377-2394, 2005

The telomerization of dimethylaminoethyl methacrylate (DMAEMA) with mercaptoethanol initiated by 2,2′-azobisisobutyronitrile was first investigated at 70 °C and the influence of the type of solvent was studied. The results showed that well-defined telomers of DMAEMA could not be synthetized via telomerization of DMAEMA in water or water/acetonitrile mixture since the telomerization reaction is in competition with the nucleophilic addition of thiol onto the monomer. Transfer constants for mercaptoethanol in benzene and acetonitrile were determined by Mayo's and O'Brien's methods. The transfer constant obtained in acetonitrile (0,6) was higher than that obtained in benzene. This difference can be explained by the fact that the thiol was consumed by two reactions: nucleophilic addition and telomerization. The influence of solvents on the polymerization kinetics was enlightened. These results were applied to the synthesis of macromonomers of DMAEMA with isocyanatoethyl methacrylate (IEM). These macromonomers were copolymerized with styrene.

The telomerization of 10-undecenol with alkyl hydrogenphosphonate was studied in order to synthesize telomers of different molecular weights. The study showed that telomers from 10-undecenol could be obtained despite the fact that the double bond has a low reactivity. The kinetic constan Kp 2 /K Tc was determined to be 7 x 10 -4 l.mol -1 . s -1 at 135°C and the transfer constant C T was 0.057. These values are normal for a low activity telogen such as hydrogenphosphonate and for slightly reactive monomers like 10-undecenol.

The synthesis of novel methacrylic phosphonated surface-active monomer by an original method is described. The crucial stage is the telomerization of undec-10-enyl acetate with dialkyl (alkyl = methyl or ethyl) hydrogenphosphonate. The phosphonated acetate obtained is selectively hydrolysed to give dialkyl(11-hydroxyundecyl)phosphonate as a precursor. The alcohol function allows setting of methacrylic side, which is highly reactive in radical polymerization. Particularly, by mono-dealkylation of dimethyl phosphonate in a selective and quantitative way, the potassium iodide permits to get, at one stage, the expected salt of sodium methyl phosphonate. The new surface-active sodium methyl(11-methacryloyloxyundecyl)phosphonate is characterized by 1 H and 31 P NMR. Its critical micelle concentration evaluated by conductometry is 2.4 × 10 -2 mol . l -1 .