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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

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 .

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

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

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 methyl methacrylate with 2-aminoethanethiol hydrochloride initiated by 2,2'-azobisisobutyronitrile, was investigated in dimethylformamide (DMF). First, the peculiar behavior of 2-aminoethanethiol was highlighted because it behaves as a peculiar transfer agent; this is because its transfer constant (C T ) is weak compared with that of other thiols. The presence of the amine function greatly disturbs the free radical telomerization reaction. Telomerization was performed in the presence of hydrochloric acid (HCl) to protect the amine group. The transfer constant was strongly influenced by the acid and water concentration. This work emphasized that the nature of the solvent plays an important role in the determination of the transfer constant. Thus, the value of C T increased from 0.23 in DMF to 0.56 in the HCl/DMF mixture. The primary and secondary amines were recovered after the reaction. The functionality of the primary and secondary amines was measured by titration. The influence of the concentration of HCl on the resulting amine functionality was investigated. The acid presence prevents the formation of secondary amines, arising from Michael's reaction, on methyl methacrylate. Finally, these results were applied to the synthesis of amine-functionalized telomers with molecular masses of 2000 to 15,000 g/mol. The amine function was correlated with the decrease of R 0 ([telogen]/[monomer]).

This article explores the use of a new relation correcting theoretical (DPn) with experimental values obtained in the dead-end polymerization of styrene with azocompound. The syntheses were realized for several starting initiator-to-monomer ratios (C0's); values comprised between 10 and 0.1%, and the experimental (DPn) were obtained by size exclusion chromatography. Concerning the theoretical (DPn), a new relation is proposed considering the loss of initiating radicals [I · ] used in primary termination and both stationary states of I · and M · (macromolecular radicals) introduced as Bamford. Finally, (DPn)cum, previously defined by us, is introduced to consider the monomer conversion during oligomerization. Our relation fit very well in a large range of C0's, contrary to the application of the usual Mayo rule, and a discussion of validity is proposed. Our model also allows the prediction of (DPn)cum in a large range of telechelic oligomers from 10 to 150. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 236–247, 2003

Styrene was polymerized with azobiscyanovaleric acid (ACVA) to obtain carboxy-telechelic polystyrene. Our aim was to synthesize an oligostyrene with a molecular weight of about 2000 g/mol. Thus, styrene was polymerized at 90 °C, where t 1/2ACVA is very short, and at very high initiator concentrations. In these conditions a new termination reaction appeared, known as the primary radical termination (PRT). At first, PRT was observed by a deviation from the simple kinetic law. Then, the constant of PRT was determined by several kinetic models to be more important than the constant of bimolecular termination. Finally, the PREDICI simulation program was used to confirm the predominance of PRT. This simulation program allowed the determination of the constant of primary radical deactivation k rr and the influence of this reaction on the conversion rate.