Speaker
Natalya Vishnevetskaya
(Fachgebiet Physik weicher Materie/Lehrstuhl für Funktionelle Materialien, Physik-Department, Technische Universität München)
Description
Diblock copolymers consisting of a thermo-responsive poly(N-isopropylmethacrylamide) (PNIPMAM block) and a zwitterionic poly(sulfobetaine) (PSB block) feature both a lower and an upper critical solution temperature (LCST and UCST) in aqueous solution. P(SB-b-NIPMAM) expected to form in water the following phases: (i) micelles with PNIPMAM shell and PSB core or vice versa at low and high temperatures and unimers and (ii) large aggregates in the intermediate temperature range, depending on the chemical structure and the molecular mass of the PSB block as well as on the presence of electrolyte.
The aggregation behavior in D2O with dual stimuli (temperature and electrolyte concentration) is studied by temperature-resolved small-angle X-ray and neutron scattering (SAXS, SANS). We have found that the aggregation of P(SB-b-NIPMAM) in D2O occurs above LCST and below UCST and that the structure depends on the blocks lengths, whereas the salt-induced structural changes were only minor.
Primary author
Natalya Vishnevetskaya
(Fachgebiet Physik weicher Materie/Lehrstuhl für Funktionelle Materialien, Physik-Department, Technische Universität München)
Co-authors
Prof.
André Laschewsky
(Institut für Chemie, Universität Potsdam; Fraunhofer Institut für Angewandte Polymerforshung, Potsdam-Golm)
Prof.
Christine M. Papadakis
(Fachgebiet Physik weicher Materie/Lehrstuhl für Funktionelle Materialien, Physik-Department, Technische Universität München)
Dr
Martine Philipp
(Technische Universität München)
Prof.
Peter Müller-Buschbaum
(Fachgebiet Physik weicher Materie/Lehrstuhl für Funktionelle Materialien, Physik-Department, Technische Universität München)
Viet Hildebrand
(Institut für Chemie, Universität Potsdam)
