We use cookies to ensure that we give you the best experience on our website. You can change your cookie settings at any time. Otherwise, we'll assume you're OK to continue.

Department of Physics

Staff profile

Publication details for Prof Tom McLeish

Greenall, Martin J., Schuetz, Peter, Furzeland, Steve, Atkins, Derek, Buzza, D. Martin A., Butler, Michael F. & McLeish, Tom C.B. (2011). Controlling the Self-Assembly of Binary Copolymer Mixtures in Solution through Molecular Architecture. Macromolecules 44(13): 5510-5519.

Author(s) from Durham


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.