Living self- assembly of block copolymers into fibre-like
structures in solution and from surfaces
By Mitchell A. Winnik
Department of Chemistry, University of Toronto, Toronto ON
Canada M5S 3H6
Fiber-like micelles formed by polyferrocenylsilane block
copolymers (PFS) in selective solvents have many features in
common with β-amyloid fibers formed by protein self assembly in
water. The two types of structures have similar dimensions
(microns in length, nanometers in diameter), similar stiffness,
and both are sensitive to fragmentation when sonicated. The most
remarkable similarity is that they appear to form by a similar
growth mechanism: nucleated growth by the condensation of polymer
molecules onto the ends of fiber fragments. A special feature of
the PFS block copolymer micelles is that they can be prepared
essentially monodisperse in length. Since the nucleation sites
appear to be the exposed crystal faces of the ends of the PFS
micelle cores, it should be possible to create these nucleation
sites at the surface of thin films of PFS homopolymer, annealed
to induce crystallization. These experiments, carried out in
collaboration with the Manners group in Bristol UK, have
generated some exciting initial results which will be reported at
the conference.
