The use of DMSO as solvent for transition metal mediated living radical polymerization was investigated using copper (I) bromide/N‐(n‐propyl)‐2‐pyridyl‐methanimine catalyst system and ethyl‐2‐bromoisobutyrate as initiator. The best conditions for polymerization in DMSO of different methacrylates (MMA, BMA, DMAEMA, HEMA) were determined. In all cases, the measured number‐average molar mass of the product increased linearly with monomer conversion in agreement with the theoretical Mn with low polydispersity products (1.16 < PDI < 1.4) achieved. Solvent was found to play a crucial role in the process. The effect of the polar solvent has been investigated and it was shown that DMSO could coordinate copper (II), increasing the activation process, or copper (I), changing the nature of the copper catalyst by competitive complexation of ligand and DMSO. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 6299–6308, 2004

A first generation phosphorus-containing dendrimer with twelve terminal benzyl dithiobenzoate functions was designed and subsequently used as a multifunctional agent to derive hybrid star copolymers consisting of a dendritic core surrounded by twelve polystyrene branches by reversible addition-fragmentation chain transfer (RAFT).

A new functional lactone, α-iodo-ε-caprolactone (αIεCL), was synthesized from ε-caprolactone by anionic activation using a non-nucleophilic strong base (lithium diisopropylamide) followed by an electrophilic substitution with iodine chloride. Ring-opening (co)polymerizations of the resulting monomer with ε-caprolactone were carried out using tin 2-ethylhexanoate as a catalyst in toluene at 100 °C. Homopolymerization of αIεCL was achieved, and poly(αIεCL) was fully characterized by SEC, (1) H NMR and elemental analysis. Random copolymerizations of αIεCL with εCL were controlled with experimental molecular weights close to the theoretical values, narrow molecular weight distributions and a good agreement between experimental and theoretical molar compositions of αIεCL.

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International audienceAmphiphilic and cationic PCL-based degradable polyester was synthesized by copper-catalyzed azide-alkyne cycloaddition (CuAAC)

A straightforward approach based on thiol-ene click chemistry was used to prepare novel functional polyesters containing amino groups. First, a series of well-defined alkene-functional poly(3caprolactone)s were prepared by ring-opening polymerization of a-allyl-3-caprolactone with 3caprolactone in toluene and in bulk using tin 2-ethylhexanoate as catalyst. These functional polyesters were fully characterized by 1 H NMR, GPC, and MALDI-TOF MS. The resulting random copolyesters were obtained with a wide range of molar masses from 3000 to 50 000 g mol À1 and a good incorporation of the a-allyl-3-caprolactone monomer unit. Then, thiol-ene reaction of alkene-functional PCL with the 2-(Boc-amino)ethanethiol was used to prepare efficiently polyesters bearing protected amino groups without chain degradation. Finally, cationic and water-soluble polyesters bearing free amino groups were recovered by cleavage of the Boc protecting group. These aminated polyesters were characterized by 1 H NMR in deuterated water.

Well-defined graft copolymers were obtained using a copper-catalysed azide-alkyne Huisgen's cycloaddition click reaction from both biocompatible and non-toxic poly(ε-caprolactone) and poly(2-methyl-2-oxazoline) homopolymers. Resulting amphiphilic copolymers proved to form micelles that could be used as potential drug carriers.