Effect of Hydrophilic Monomer Distribution on Self-Assembly of a pH-Responsive Copolymer: Spheres, Worms and Vesicles from a Single Copolymer Composition

Zhang, Junliang; Farias-Mancilla, Barbara; Kulai, Ihor; Höppener, Stephanie; Lonetti, Barbara; Prevost, Sylvain; Ulbrich, Jens; Destarac, Mathias; Colombani, Olivier; Schubert, Ulrich S.; Sanchez, Carlos Guerrero; Harrisson, Simon

Abstract:

A series of copolymers containing 50 mol % acrylic acid (AA) and 50 mol % butyl acrylate (BA) but with differing composition profiles ranging from an AA-BA diblock copolymer to a linear gradient poly(AA-grad-BA) copolymer were synthesized and their pH-responsive self-assembly behavior was investigated. While assemblies of the AA-BA diblock copolymer were kinetically frozen, the gradient-like compositions underwent reversible changes in size and morphology in response to changes in pH. In particular, a diblock copolymer consisting of two random copolymer segments of equal length (16 mol % and 84 mol % AA content, respectively) formed spherical micelles at pH >5, a mix of spherical and wormlike micelles at pH 5 and vesicles at pH 4. These assemblies were characterized by dynamic light scattering, cryo-transmission electron microscopy and small angle neutron scattering.

Year:

2021

Type of Publication:

Article

Journal:

Angewandte Chemie International Edition

Volume:

60

Pages:

4925 - 4930

DOI:

https://doi.org/10.1002/anie.202010501