10.1021/la204100d.s001
Cameron
P. Glagola
Cameron
P.
Glagola
Lia M. Miceli
Lia M.
Miceli
Marissa A. Milchak
Marissa A.
Milchak
Emily H. Halle
Emily H.
Halle
Jennifer L. Logan
Jennifer L.
Logan
Polystyrene–Poly(ethylene
oxide) Diblock Copolymer:
The Effect of Polystyrene and Spreading Concentration at the Air/Water
Interface
American Chemical Society
2016
microphase separation
polymer templates
impact
Diblock Copolymer
PS
interface
PEO
amphiphilic diblock copolymer
oxide
AFM results
200 000
nanosized domains
polymer composition
sample
concentration
AFM analysis
force microscopy
weight percent
polymer behavior
Spreading Concentration
nanostructure
dot
2016-02-21 17:12:20
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Polystyrene_Poly_ethylene_oxide_Diblock_Copolymer_The_Effect_of_Polystyrene_and_Spreading_Concentration_at_the_Air_Water_Interface/2538739
Polystyrene-<i>block</i>-poly(ethylene oxide)
(PS-PEO)
is an amphiphilic diblock copolymer that undergoes microphase separation
when spread at the air/water interface, forming nanosized domains.
In this study, we investigate the impact of PS by examining a series
of PS-PEO samples containing constant PEO (∼17 000 g·mol<sup>–1</sup>) and variable PS (from 3600 to 200 000 g·mol<sup>–1</sup>) through isothermal characterization and atomic force
microscopy (AFM). The polymers separated into two categories: predominantly
hydrophobic and predominantly hydrophilic with a weight percent of
PEO of ∼20% providing the boundary between the two. AFM results
indicated that predominantly hydrophilic PS-PEO forms dots while more
hydrophobic samples yield a mixture of dots and spaghetti with continent-like
structures appearing at ∼7% PEO or less. These structures reflect
a blend of polymer spreading, entanglement, and vitrification as the
solvent evaporates. Changing the spreading concentration provides
insight into this process with higher concentrations representing
earlier kinetic stages and lower concentrations demonstrating later
ones. Comparison of isothermal results and AFM analysis shows how
polymer behavior at the air/water interface correlates with the observed
nanostructures. Understanding the impact of polymer composition and
spreading concentration is significant in leading to greater control
over the nanostructures obtained through PS-PEO self-assembly and
their eventual application as polymer templates.