Controlling the self-assembly of binary copolymer mixtures in solution through molecular architecture

M.J. Greenall, P. Schuetz, S. Furzeland, D. Atkins, D.M.A. Buzza, M.F. Butler, T.C.B. McLeish

Research output: Contribution to journalArticlepeer-review

31 Citations (SciVal)

Abstract

We present a combined experimental and theoretical study on the role of copolymer architecture in the self-assembly of binary PEO-PCL mixtures in water-THF and show that altering the chain geometry and composition of the copolymers can control the form of the self-assembled structures and lead to the formation of novel aggregates. First, using transmission electron microscopy and turbidity measurements, we study a mixture of sphere-forming and lamella-forming PEO-PCL copolymers and show that increasing the molecular weight of the lamella-former at a constant ratio of its hydrophilic and hydrophobic components leads to the formation of highly curved structures even at low sphere-former concentrations. This result is explained using a simple argument based on the effective volumes of the two sections of the diblock and is reproduced in a coarse-grained mean-field model: self-consistent field theory (SCFT). Using further SCFT calculations, we study the distribution of the two copolymer species within the individual aggregates and discuss how this affects the self-assembled structures. We also investigate a binary mixture of lamella-formers of different molecular weights and find that this system forms vesicles with a wall thickness intermediate to those of the vesicles formed by the two copolymers individually. This result is also reproduced using SCFT. Finally, a mixture of sphere-former and a copolymer with a large hydrophobic block is shown to form a range of structures, including novel elongated vesicles.
Original languageEnglish
Pages (from-to)5510-5519
Number of pages10
JournalMacromolecules
Volume44
Issue number13
Early online date16 Jun 2011
DOIs
Publication statusPublished - 12 Jul 2011

Fingerprint

Dive into the research topics of 'Controlling the self-assembly of binary copolymer mixtures in solution through molecular architecture'. Together they form a unique fingerprint.

Cite this