Bandeau LBPB

Polymères biodégradables : synthèse et applications

  • Microphase Separation of Polybutyrolactone-​Based Block Copolymers with Sub-​20 nm Domains
    F. Kayser, G. Fleury, S. Thongkham, C. Navarro, B. Martin-Vaca, D. Bourissou
    Macromolecules 2018, 51, 6534-6541.

    TOC Macromolecules Franck

    Polybutyrolactone tri- and diblock copolymers with well-defined structures and narrow molar distributions were prepared by trifluoromethanesulfonic acid-organocatalyzed ring-opening polymerization of β-butyrolactone initiated with dihydroxylated poly(hydrogenated butadiene) and hydroxylated polystyrene. Study of the phase separation behavior of these block copolymers in the bulk and in thin film shows their ability to segregate even for low molecular weights, giving rise to spherical, cylindrical, and lamellar morphologies with periodicities in the range 10–20 nm. The Flory–Huggins interaction parameters estimated from the order-to-disorder transition temperatures are in the same range or higher than those of other block copolymers associating biodegradable and polyolefin blocks.

  • Impact of the architecture on the crystallization kinetics of poly(ε-​caprolactone)​/poly(trimethylene carbonate) block copolymers
    R. V. Castillo, G. Fleury,* C. Navarro, A. Couffin, D. Bourissou,* B. Martin-Vaca*
    Eur. Polym. J. 2017, 95, 711-727.

    EUR polym 2017
    Well defined block copolymer architectures based on poly(ε-caprolactone) and poly(trimethylene carbonate) were prepared thanks to the methane sulfonic acid (MSA) organocatalyzed ROP of the corresponding monomers. The interplay between the crystallization kinetics, self-assembling behavior and superstructural morphology was investigated. In order to probe the influence of the block copolymer architecture (molecular weight, number of blocks and sequence), kinetics theories of polymer crystallization were applied to the isothermal crystallization kinetics data obtained by differential scanning calorimetry and polarized optical microscopy. The results suggest that the PCL crystallization kinetic is only slightly disturbed by the segregation strength for weakly segregated systems while the block copolymer sequence shows a strong impact on the overall crystallization kinetics, and particularly on the nucleation step due to topological constraints.

  • Ring-opening polymerization of ε-caprolactone catalyzed by ionic hydrogen bond activation with bis-pyridiniums
    G. Gontard, A. Amgoune*, D. Bourissou*
    Polym. Sci., Part A: Polym. Chem. 2016, 54, 3253-3256.

    toc gwen

    Pyridinium and bispyridinium salts are shown to be efficient ionic hydrogen bond catalysts for the controlled ring–opening polymerization of ε–caprolactone. The catalytic activity is significantly enhanced thanks to the participation of the two hydrogen bond donor sites in the monomer activation.

  • PEG–PLGA copolymers bearing carboxylated side chains: Novel hydrogels with enhanced crosslinking via ionic interactions
    S. J. Buwalda, A. Amgoune, D. Bourissou
    Polym. Sci., Part A: Polym. Chem. 2016, 54, 1222-1227

    toc sytze

    Novel water-soluble amphiphilic block copolymers with pendant carboxylic acid groups are synthesized and used for the preparation of ionically crosslinked hydrogels. d,l-Lactide (DLLA) and l−3-(2-benzyloxycarbonyl)ethyl-1,4-dioxane-2,5-dione (BED) are copolymerized at different ratios via organo-catalyzed ring-opening polymerization using a hydroxyl-terminated poly(ethylene glycol) (PEG–OH) macroinitiator. Dynamic light-scattering experiments show that, at low concentrations, aqueous solutions of these PEG-P(BED-DLLA) copolymers form micelles and aggregates. At higher concentrations, thermo-sensitive gels are obtained, exhibiting a reversible gel-to-sol transition upon a temperature increase. Ionic interactions between the COOH groups and metal ions (Cu2+ or Ca2+) are shown to significantly shift the gel–sol transition to higher temperatures. Thus, the introduction of COOH groups significantly enhances the water solubility of the amphiphilic PEG–polyester copolymer and allows additional crosslinking interactions to form functionalized hydrogels with improved physical properties, making this new class of hydrogels interesting for various applications.

  • Direct ring-opening of lactide with amines: application to the organo-catalyzed preparation of amide end-capped PLA and to the removal of residual lactide from PLA samples
    A. Alba, O. Thillaye du Boullay, B. Martin-Vaca*, D. Bourissou*
    Polym. Chem., 2015, 6, 989-997

    Polym Chem PLA

    Amide end-capped PLA can be efficiently prepared by taking advantage of the ability of amines to ring-open lactide. A two-step one-pot strategy has been developed in which primary or secondary amines are reacted with an excess of lactide prior to the addition of the ROP catalyst, DBU. Amide-functionalised PLA of different structures (linear, telechelic, star-shaped etc.) have been prepared using polyfunctional amines as initiators. Primary amines supported on resins also readily react with lactide, and this has been applied to remove unreacted monomer from PLA samples without affecting the polymer properties.

  • O-Carboxyanhydrides: Useful Tools for the Preparation of Well-Defined Functionalized Polyesters
    B. Martin Vaca * and D. Bourissou *
    ACS Macro Lett., 2015, 4 , 792–798

    ACS Macroletters 2015 OCA
    Over the last ten years, O-carboxyanhydrides (OCA) have attracted increasing attention as ring-opening polymerization (ROP) monomers. They are readily available from α-hydroxyacids and are significantly more reactive than 1,4-dioxane-2,5-diones. Thus, softer catalysts and milder reaction conditions can be used, allowing for a better control of the polymerization. Most attractive are the functionalized OCA that enable the introduction of functional groups along the polyester backbone and thereby vary and finely tune their physicochemical properties. In this viewpoint, the achievements made over the last years are critically overviewed. Particular attention is paid to the different catalytic approaches that have been reported for the ROP of these heterocycles and to the comparison with lactide ROP. In addition, the most representative examples of functionalized polyesters and polymer conjugates prepared from OCA are discussed.

  • Selective O-acyl ring-opening of b-butyrolactone catalyzed by trifluoromethane sulfonic acid: application to the preparation of well-defined block copolymers
    A. Couffin, B. Martín-Vaca, D. Bourissou, C. Navarro
    Polymer Chem. 2014, 5, 161.


    A detailed study of b-butyrolactone (b-BL) ring-opening polymerization (ROP) with methane and trifluoromethane sulfonic acids (MSA and HOTf, respectively) is reported. HOTf affords the best results in terms of activity and selectivity, leading to PBL of controlled molecular weights (Mn up to 8 200 g/mol) and narrow distributions (Ð < 1.25). Ring-opening of b-BL occurs selectively via O-acyl bond cleavage and crotonisation reactions do not occur to a significant extent. This leads to hydroxyl terminated PBL that are able to initiate efficiently ROP of e-caprolactone (e-CL). Using mono and dihydroxylated initiators, including macroinitiators, a variety of well-defined block copolymers have been prepared upon successive monomer addition.

  • Ring-Opening Polymerization with Zn(C6F5)2‑Based Lewis Pairs: Original and Efficient Approach to Cyclic Polyesters.
    E. Piedra-Arroni, C. Ladavière, A. Amgoune,* D. Bourissou*
    J. Am. Chem. Soc. 2013, 135, 13306


    Dual systems combining Zn(C6F5)2 with an organic base (an amine or a phosphine) promote the controlled ring–opening polymerization of lactide and e–caprolactone. The Lewis pairs cooperate to activate the monomers, affording well–defined high–molecular weight cyclic polyesters. Efficient chain–extension gives access to cyclic block copolymers.

  • Y-Shaped mPEG-PLA Cabazitaxel Conjugates: Well-Controlled Synthesis by Organocatalytic Approach and Self-Assembly into Interface Drug-Loaded Core–Corona Nanoparticles
    F. Bensaid, O. Thillaye du Boullay, A. Amgoune, C. Pradel, L. H. Reddy, E. Didier, S. Sablé, G. Louit, D. Bazile, D. Bourissou*
    Biomacromolecules, 2013, 14, 1189.


    A well-defined poly(ethylene glycol) methyl ether-b-poly(lactic acid) copolymer (mPEG-PLA) featuring a new, Y-shaped, architecture with a hydroxyl functional group between the two blocks has been prepared and thoroughly characterized. The functional copolymer was then readily coupled to diglycolyl-cabazitaxel. The resulting copolymer conjugates assembled into stable and monodisperse nanoparticles (NPs) in aqueous suspension. The architecture of the copolymer conjugate is shown to impact the spatial distribution of the drug within the nanoparticles. With the Y-shaped architecture, cabazitaxel was found localized at the interface of the hydrophobic PLA core and the hydrophilic mPEG corona of the NPs. Preliminary in vitro release studies reveal dependence on the architecture of the copolymer conjugate. This new approach offers promising perspectives to finely tune the position of the active ingredient in polymeric nanoparticles.

  • PLGA Microparticles with Zero-Order Release of the Labile Anti-Parkinson Drug Apomorphine
    C. Regnier-Delplace, O. Thillaye du Boullay, F. Siepmann, B. Martin-Vaca, N. Degrave, P. Demonchaux, O. Jentzer, D. Bourissou, J. Siepmann*
    Int. J. Pharm. et J. Control. Release 2013, 166, 256.


    Novel PLGA derivatives bearing carboxylated side chains have been synthesized and used to encapsulate the fragile drug apomorphine HCl with a solid-in-oil-in-water solvent extraction/evaporation method. Blends of D,L-lactide and L-3-(2-Benzyloxycarbonyl)Ethyl-1,4-Dioxane-2,5-dione (BED) were co-polymerized at different ratios via ring-opening using benzyl alcohol as initiator. Optionally, the ester groups in the side chains as well as the terminal ester groups were hydrogenolyzed (leading to free -COOH groups). Importantly, microparticles based on the new polymers bearing carboxylic groups in the polymeric side chains: (i) allowed a significant reduction of the amount of residual solvent (dichloromethane), and (ii) provided different types of drug release patterns compared to microparticles based on "conventional" PLGAs (at least partially due to altered polymer degradation kinetics).

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