TY  - JOUR
A1  - Casse, Olivier
A1  - Shkilnyy, Andriy
A1  - Linders, Jürgen
A1  - Mayer, Christian
A1  - Häussinger, Daniel
A1  - Völkel, Antje
A1  - Thünemann, Andreas F.
A1  - Dimova, Rumiana
A1  - Cölfen, Helmut
A1  - Meier, Wolfgang P.
A1  - Schlaad, Helmut
A1  - Taubert, Andreas
T1  - Solution behavior of double-hydrophilic block copolymers in dilute aqueous solution
JF  - Macromolecules : a publication of the American Chemical Society
N2  - The self-assembly of double-hydrophilic poly(ethylene oxide)-poly(2-methyl-2-oxazoline) diblock copolymers in water has been studied. Isothermal titration calorimetry, small-angle X-ray scattering, and analytical ultracentrifugation suggest that only single polymer chains are present in solution. In contrast, light scattering and transmission electron microscopy detect aggregates with radii of ca. 100 nm. Pulsed field gradient NMR spectroscopy confirms the presence of aggregates, although only 2% of the polymer chains undergo aggregation. Water uptake experiments indicate differences in the hydrophilicity of the two blocks, which is believed to be the origin of the unexpected aggregation behavior (in accordance with an earlier study by Ke et al. [Macromolecules 2009, 42, 5339-5344]). The data therefore suggest that even in double-hydrophilic block copolymers, differences in hydrophilicity are sufficient to drive polymer aggregation, a phenomenon that has largely been overlooked or ignored so far.
Y1  - 2012
U6  - https://doi.org/10.1021/ma300621g
SN  - 0024-9297
VL  - 45
IS  - 11
SP  - 4772
EP  - 4777
PB  - American Chemical Society
CY  - Washington
ER  -