Preparation of non-spherical particles from amphiphilic block copolymers

Kempe, K., Wylie, R. A., Dimitriou, M. D., Tran, H., Hoogenboom, R., Schubert, U. S., Hawker, C. J., Campos, L. M. and Connal, L. A.
J. Polym. Sci. Part A: Polym. Chem.
20 October

Simple self-assembly techniques to fabricate non-spherical polymer particles, where surface composition and shape can be tuned through temperature and the choice of non-solvents was developed. A series of amphiphilic polystyrene-b-poly(2-ethyl-2-oxazoline) block copolymers were prepared and through solvent exchange techniques using varying non-solvent composition a range of non-spherical particles were formed. Faceted phase separated particles approximately 300 nm in diameter were obtained when self-assembled from tetrahydrofuran (THF) into water compared with unique large multivesicular particles of 1200 nm size being obtained when assembled from THF into ethanol (EtOH). A range of intermediate structures were also prepared from a three part solvent system THF/water/EtOH. These techniques present new tools to engineer the self-assembly of non-spherical polymer particles.