TY - GEN
T1 - Structural study of star polyelectrolytes and their porous multilayer assembly in solution
AU - Xu, Weinan
AU - Malak, Sidney T.
AU - Plamper, Felix A.
AU - Synatschke, Christopher V.
AU - Müller, Axel H.E.
AU - Heller, William T.
AU - Melnichenko, Yuri B.
AU - Tsukruk, Vladimir V.
N1 - Publisher Copyright:
© Springer International Publishing Switzerland 2015.
PY - 2015
Y1 - 2015
N2 - Star polyelectrolytes with responsive properties to external stimuli, such as pH, temperature and ionic condition, were utilized to fabricate layer-by-layer (LbL) microcapsules. The microstructure of star polyelectrolytes was first studied in semi-dilute solution by in situ small-angle neutron scattering (SANS). These measurements show that with the addition of salts, arms of strong cationic star polyelectrolytes will contract and the spatial ordering of the stars would be interrupted. SANS measurements were also performed on the microcapsules in order to study their internal structure and responsive properties in solution. The results show that with the increase of shell thickness, microcapsules undergo a change of fractal dimension. Microcapsules with thinner shell have a surface fractal structure with rough interface, while those with thicker shell generally have a mass fractal structure of 3D random network. With the change of surrounding environment (pH, temperature, or ionic condition), the morphology and permeability of microcapsules are changed concurrently, for example, with the addition of multivalent salt, there isa surface- to mass-fractal transition, with the correlation length decreasing by around 50 %. This study provides insight into the mechanism of the responsiveness of novel star polyelectrolytes and their assembled multilayer structures.
AB - Star polyelectrolytes with responsive properties to external stimuli, such as pH, temperature and ionic condition, were utilized to fabricate layer-by-layer (LbL) microcapsules. The microstructure of star polyelectrolytes was first studied in semi-dilute solution by in situ small-angle neutron scattering (SANS). These measurements show that with the addition of salts, arms of strong cationic star polyelectrolytes will contract and the spatial ordering of the stars would be interrupted. SANS measurements were also performed on the microcapsules in order to study their internal structure and responsive properties in solution. The results show that with the increase of shell thickness, microcapsules undergo a change of fractal dimension. Microcapsules with thinner shell have a surface fractal structure with rough interface, while those with thicker shell generally have a mass fractal structure of 3D random network. With the change of surrounding environment (pH, temperature, or ionic condition), the morphology and permeability of microcapsules are changed concurrently, for example, with the addition of multivalent salt, there isa surface- to mass-fractal transition, with the correlation length decreasing by around 50 %. This study provides insight into the mechanism of the responsiveness of novel star polyelectrolytes and their assembled multilayer structures.
UR - http://www.scopus.com/inward/record.url?scp=84950289068&partnerID=8YFLogxK
U2 - 10.1007/978-3-319-20875-6_11
DO - 10.1007/978-3-319-20875-6_11
M3 - Conference contribution
AN - SCOPUS:84950289068
SN - 9783319208749
T3 - Springer Proceedings in Physics
SP - 299
EP - 315
BT - Physics of Liquid Matter
A2 - Bulavin, Leonid
A2 - Lebovka, Nikolai
PB - Springer Science and Business Media, LLC
T2 - 6th International Conference on Physics of Liquid Matter: Modern Problems, PLMMP 2014
Y2 - 23 May 2014 through 27 May 2014
ER -