TY  - JOUR
A1  - de Molina, Paula Malo
A1  - Ihlefeldt, Franziska Stefanie
A1  - Prevost, Sylvain
A1  - Herfurth, Christoph
A1  - Appavou, Marie-Sousai
A1  - Laschewsky, André
A1  - Gradzielski, Michael
T1  - Phase Behavior of Nonionic Microemulsions with Multi-end-capped Polymers and Its Relation to the Mesoscopic Structure
T2  - Langmuir
N2  - The polymer architecture of telechelic or associative polymers has a large impact on the bridging of self-assembled structures. This Work presents: the phase behavior, small angle neutron scattering (SANS), dynamic light scattering (DLS), and fluorescence correlation spectroscopy (FCS) of a nonionic oil-in-water (O/W) microemulsion with hydrophobically end-capped multiarm polymers With functionalities f = 2, 3, and 4. For high polymer concentrations and large average interdroplet distance relative to the end-to-end distance of the polymer, d/R-ee; the system phase separates into a dense, highly connected droplet network phase, in equilibrium with a dilute phase. The extent of the two-phase region is larger for polymers With similar length but higher f. The Interaction potential between the droplets in the presence of polymer has both a repulsive and an attractive contribution as a result of the counterbalancing effects of the exclusion by polymer chains and bridging between droplets. This study experimentally demonstrates that higher polymer functionalities induce a stronger attractive force between droplets, which is responsible for a more extended phase separation region., and correlate with lower Collective droplet diffusivities and higher amplitude of the second relaxation time in DLS. The viscosity and the droplet self-diffusion obtained from FCS, however, are dominated by the end-capped chain concentration.
Y1  - 2015
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/38930
SN  - 0743-7463
VL  - 31
IS  - 18
SP  - 5198
EP  - 5209
PB  - American Chemical Society
CY  - Washington
ER  -