TY  - JOUR
A1  - Adelsberger, Joseph
A1  - Kulkarni, Amit
A1  - Jain, Abhinav
A1  - Wang, Weinan
A1  - Bivigou Koumba, Achille Mayelle
A1  - Busch, Peter
A1  - Pipich, Vitaliy
A1  - Holderer, Olaf
A1  - Hellweg, Thomas
A1  - Laschewsky, André
A1  - Müller-Buschbaum, Peter
A1  - Papadakis, Christine M.
T1  - Thermoresponsive PS-b-PNIPAM-b-PS micelles : aggregation behavior, segmental dynamics, and thermal response
N2  - We have studied I lie thermal behavior of amphiphilic, symmetric triblock copolymers having short, deuterated polystyrene (PS) end blocks and a large poly(N-isopropylacrylarnicle) (PNIPAM) middle block exhibiting a lower critical solution temperature (LCST) in aqueous solution. A wide range of concentrations (0.1-300 mg/mL) is investigated using it number of analytical methods such as fluorescence correlation spectroscopy (FCS), turbidimetry, dynamic light scattering (DLS), small-angle neutron scattering (SANS), and neutron spin-echo spectroscopy (NSE). The critical micelle concentration is determined using FCS to be 1 mu M or less. The collapse of the micelles at the LCST is investigated using turbidimetry and DLS and shows a weak dependence on the degree of polymerization of the PNIPAM block. SANS with contrast matching allows its to reveal the core-shell Structure of the micelles as well as their correlation as a function of temperature. The segmental dynamics of the PNIPAM shell are studied as a function of temperature and arc found to be faster in the collapsed state than in the swollen state. The mode detected has a linear dispersion in q(2) and is found to be faster in the collapsed state as compared to the swollen state. We attribute this result to the averaging over mobile and immobilized segments.
Y1  - 2010
UR  - http://pubs.acs.org/journal/mamobx
U6  - https://doi.org/10.1021/Ma902714p
SN  - 0024-9297
ER  -