TY  - JOUR
A1  - Zhong, Qi
A1  - Metwalli, Ezzeldin
A1  - Rawolle, Monika
A1  - Kaune, Gunar
A1  - Bivigou Koumba, Achille Mayelle
A1  - Laschewsky, Andre
A1  - Papadakis, Christine M.
A1  - Cubitt, Robert
A1  - Wang, Jiping
A1  - Mueller-Buschbaum, Peter
T1  - Influence of Hydrophobic Polystyrene Blocks on the Rehydration of Polystyrene-block-poly(methoxy diethylene glycol acrylate)-block-polystyrene Films Investigated by in Situ Neutron Reflectivity
JF  - Macromolecules : a publication of the American Chemical Society
N2  - The rehydration of thermoresponsive polystyrene-block-poly(methoxy diethylene glycol acrylate)-block-polystyrene (PS-b-PMDEGA-b-PS) films forming a lamellar microphase-separated structure is investigated by in situ neutron reflectivity in a D2O vapor atmosphere. The rehydration of collapsed PS-b-PMDEGA-b-PS films is realized by a temperature change from 45 to 23 degrees C and comprises (1) condensation and absorption of D2O, (2) evaporation of D2O, and (3) reswelling of the film due to internal rearrangement. The hydrophobic PS layers hinder the absorption of condensed D2O, and a redistribution of embedded D2O between the hydrophobic PS layers and the hydrophilic PMDEGA layers is observed. In contrast, the rehydration of semiswollen PS-b-PMDEGA-b-PS films (temperature change from 35 to 23 degrees C) shows two prominent differences: A thicker D2O layer condenses on the surface, causing a more enhanced evaporation of D2O. The rehydrated films differ in film thickness and volume fraction of D2O, which is due to the different thermal protocols, although the final temperature is identical.
Y1  - 2016
U6  - https://doi.org/10.1021/acs.macromol.5b02279
SN  - 0024-9297
SN  - 1520-5835
VL  - 49
SP  - 317
EP  - 326
PB  - American Chemical Society
CY  - Washington
ER  -