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Abstract
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Y-type block copolymers were synthesized based on the poly(ethylene glycol) (PEG), polythiophene (PTh), and
poly(3-dodecyl thiophene) (PDDTh) precursors including PEG-b-(PTh)2 and PEG-b-(PDDTh)2. Polymers were
applied in designing the semiglobular (semiglob(PEG-star-PTh)) and globular (glob(PEG-star-PDDTh)) nanostructures, in which the PEG lamellar crystals were confned between the PTh and PDDTh chains without and
with alkyl side chains, respectively. The designed scrolled confgurations were comprehensively investigated
from the perspectives of curvature, crystal dimension, side chain effect, etc. Thanks to a low enough crystallization temperature (Tc ¼ 10 �C), the PEG blocks were capable of being assembled into the ordered lamellar
structures, which was verifed by the selected area electron diffraction (SAED) patterns. According to (120)
growth prisms in grazing incidence wide-angle X-ray scattering (GIWAXS), the average d-spacing values of 4.70
and 4.75 Å were acquired for the sandwiched PEG crystals between PTh and PDDTh chains, respectively,
demonstrating the higher ordering in alkyl side chain-less systems. The molecular weights of PDDTh and PTh
arms were to some extent the same and this was the role of alkyl side chains in PDDTh chains which provided a
higher surface stress on the PEG arrangements. The narrower PEG crystals (16–22 nm versus 45–50 nm) as well
as a higher degree of curvature were reached in the glob(PEG-star-PDDTh) nanostructures.
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