TY  - JOUR
AU  - Schmid, Andreas Josef
AU  - Riest, Jonas
AU  - Eckert, Thomas
AU  - Lindner, Peter
AU  - Naegele, Gerhard
AU  - Richtering, Walter
TI  - Comparison of the Microstructure of Stimuli Responsive Zwitterionic PNIPAM-co-Sulfobetaine Microgels with PNIPAM Microgels and Classical Hard-Sphere Systems
JO  - Zeitschrift für physikalische Chemie
VL  - 228
IS  - ISSN (Online) 2196-7156, ISSN (Print) 0942-9352
SN  - 0942-9352
CY  - Berlin
PB  - De @Gruyter
M1  - FZJ-2014-05340
SP  - 1033-1052
PY  - 2014
AB  - In this study, we compare the experimental static structure factors of concentrated solutions of amphoteric poly(N-isopropylacrylamide) (PNIPAM) microgels with those of the polydisperse hard-sphere model. We use zwitterionic microgels as model systems for amphoteric microgels with an equal amount of positive and negative charges located in a defined distance. Using small angle neutron scattering (SANS), we measure the static structure factors, SM(q), of a series of zwitterionic microgels with increasing amount of zwitterion, including a reference sample of pure PNIPAM. The experimental SM(q) is compared with predictions based on the Percus-Yevick approximation for hard spheres. We also compare with the PNIPAM reference sample measured for zwitterionic microgels. We find no significant influence of the zwitterionic comonomer on the effective pair potential. The PNIPAM and the zwitterionic microgels can be described by the hard-sphere model for smaller volume fractions ϕT ≲ 0.4 only.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000347491400006
DO  - DOI:10.1515/zpch-2014-0559
UR  - https://juser.fz-juelich.de/record/171775
ER  -