Simple In-Based Dual Catalyst Enables Significant Progress in ε-Decalactone Ring-Opening (Co)polymerization
S. Thongkham, J. Monot, B. Martin-Vaca, D. Bourissou
Macromolecules, 2019, 52, 8103–8113.
A dual catalyst associating InCl3 and triethylamine was found to promote controlled ring-opening polymerization of ε-decalactone (ε-DL), a monomer derived from sustainable resources. Polydecalactones (PDL) of well-defined structures with Mn up to 30 000 g/mol (Đ ≈ 1.2) have been obtained free of catalytic residues under mild conditions (toluene, 3M, 60 °C, 1–20 h). Besides the typical ester end-capped PDLs, amide end groups have been installed thanks to the ability of the dual catalyst to perform with primary amines as initiators. Block PDL-b-PCL/PCL-b-PDL and random P(DL-r-CL) copolymers have been also prepared by sequential and simultaneous ROP with ε-caprolactone, respectively. The absence of undesirable transesterifications reactions, as apparent from NMR, SEC, and DSC analyses, enable the preparation of well-defined copolymers.
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.
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.
- 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
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
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.
Biodegradables polymers : synthesis and applications