Characterization of Diblock Copolymers by Capillary Electrophoresis: From Electrophoretic Mobility Distribution to Distribution of Composition Auteur(s): Phimphachanh A., Chamieh Joseph, Leclercq Laurent, Harrisson Simon, Destarac Mathias, Lacroix-Desmazes Patrick, Gerardin Corine, In M., Cottet Hervé (Article) Publié: Macromolecules, vol. 53 p.334-345 (2020) Texte intégral en Openaccess : Ref HAL: hal-02462075_v2 DOI: 10.1021/acs.macromol.9b01978 WoS: 000507721500036 Exporter : BibTex | endNote Résumé: Free solution capillary-electrophoresis (CE) is a powerful separation technique for the characterization of diblock copolymers. In this work, four series of double-hydrophilic anionic and cationic block copolymers, namely, poly(acrylamide)-block-poly(acrylic acid) (PAM-b-PAA), poly(acrylamide)-block-poly((3-acrylamidopropyl)trimethylammonium chloride) (PAM-b-PAPTAC), poly(ethylene oxide)-block-poly(acrylic acid) (PEO-b-PAA) and poly(poly(ethylene glycol) methyl ether acrylate)-block-poly(acrylic acid) (P(PEGA)-b-PAA), were synthesized by reversible additionfragmentation chain transfer (RAFT) polymerization and characterized by CE. The electrophoretic mobility distributions of the copolymers were transformed into distributions of composition ratio by introducing a retardation parameter, Xexp,, that represents the hydrodynamic drag retardation due to the neutral block of the copolymer. A linear correlation between Xexp and the ratio of the degrees of polymerization of each blocks was experimentally established and was consistent with the model of electrophoretic mobility of composite macromolecules with hydrodynamic coupling. Finally, the comparison of the distributions between the different copolymer families was significantly improved by considering the distributions in composition ratio compared to the electrophoretic mobility distributions, since it takes into account the differences in solvation, expansion and drag force according to the chemical nature of the blocks. |