TY - JOUR
T1 - The collapse transition and the segmental dynamics in concentrated micellar solutions of P(S-b-NIPAM) diblock copolymers
AU - Adelsberger, Joseph
AU - Meier-Koll, Andreas
AU - Bivigou-Koumba, Achille M.
AU - Busch, Peter
AU - Holderer, Olaf
AU - Hellweg, Thomas
AU - Laschewsky, André
AU - Müller-Buschbaum, Peter
AU - Papadakis, Christine M.
N1 - Funding Information:
We kindly acknowledge the given beam time by the Jülich Centre for Neutron Science at FRM II. This work was supported by the DFG priority program SPP1259 “Intelligente Hydrogele” (Pa771/4, Mu1487/8, La611/7, He2995/2). A. M. Bivigou-Koumba gratefully acknowledges a personal grant from Deutscher Akademischer Austauschdienst (DAAD).
PY - 2011/4
Y1 - 2011/4
N2 - We investigate concentrated solutions of poly (styrene-b-N-isopropyl acrylamide) (P(S-b-NIPAM)) diblock copolymers in deuterated water (D2O). Both structural changes and the changes of the segmental dynamics occurring upon heating through the lower critical solution temperature (LCST) of PNIPAM are studied using small-angle neutron scattering and neutron spin-echo spectroscopy. The collapse of the micellar shell and the cluster formation of collapsed micelles at the LCST as well as an increase of the segmental diffusion coefficient after crossing the LCST are detected. Comparing to our recent results on a triblock copolymer P(S-b-NIPAM-b-S) [25], we observe that the collapse transition of P(S-b-NIPAM) is more complex and that the PNIPAM segmental dynamics are faster than in P(S-b-NIPAM-b-S).
AB - We investigate concentrated solutions of poly (styrene-b-N-isopropyl acrylamide) (P(S-b-NIPAM)) diblock copolymers in deuterated water (D2O). Both structural changes and the changes of the segmental dynamics occurring upon heating through the lower critical solution temperature (LCST) of PNIPAM are studied using small-angle neutron scattering and neutron spin-echo spectroscopy. The collapse of the micellar shell and the cluster formation of collapsed micelles at the LCST as well as an increase of the segmental diffusion coefficient after crossing the LCST are detected. Comparing to our recent results on a triblock copolymer P(S-b-NIPAM-b-S) [25], we observe that the collapse transition of P(S-b-NIPAM) is more complex and that the PNIPAM segmental dynamics are faster than in P(S-b-NIPAM-b-S).
KW - Block copolymers
KW - Neutron spin-echo spectroscopy
KW - Responsive polymers
KW - Small-angle neutron scattering
UR - http://www.scopus.com/inward/record.url?scp=79959200227&partnerID=8YFLogxK
U2 - 10.1007/s00396-011-2382-3
DO - 10.1007/s00396-011-2382-3
M3 - Article
AN - SCOPUS:79959200227
SN - 0303-402X
VL - 289
SP - 711
EP - 720
JO - Colloid and Polymer Science
JF - Colloid and Polymer Science
IS - 5-6
ER -