Abstract
Self-assembly of block copolymers provides numerous opportunities to create
functional materials, utilizing self-assembled microdomains with a variety of
morphology and periodic architectures as templates for functional nanofi llers. Here
new progress is reported toward the fabrication of thermally responsive and electrically
conductive polymeric self-assemblies made from a water-soluble poly(thiophene)
derivative with short poly(ethylene oxide) side chains and Pluronic L62 block
copolymer solution in water. The structural and electrical properties of conjugated
polymer-embedded self-assembled architectures are investigated by combining
small-angle neutron and X-ray scattering, coarse-grained molecular dynamics
simulations, and impedance spectroscopy. The L62 solution template organizes the
conjugated polymers by stably incorporating them into the hydrophilic domains
thus inhibiting aggregation. The changing morphology of L62 during the micellarto-
lamellar phase transition defi nes the embedded conjugated polymer network. As a
result, the conductivity is strongly coupled to the structural change of the templating
L62 phase and exhibits thermally reversible behavior with no signs of quenching of
the conductivity at high temperature. This study shows promise for enabling more
fl exibility in processing and utilizing water-soluble conjugated polymers in aqueous
solutions for self-assembly based fabrication of stimuli-responsive nanostructures
and sensory materials.
