TY - JOUR
AU - Malo de Molina, Paula
AU - Ihlefeldt, Franziska Stefanie
AU - Prévost, Sylvain
AU - Herfurth, Christoph
AU - Appavou, Marie-Sousai
AU - Laschewsky, André
AU - Gradzielski, Michael
TI - Phase Behavior of Nonionic Microemulsions with Multi-end-capped Polymers and Its Relation to the Mesoscopic Structure
JO - Langmuir
VL - 31
IS - 18
SN - 1520-5827
CY - Washington, DC
PB - ACS Publ.
M1 - FZJ-2015-07110
SP - 5198 - 5209
PY - 2015
N1 - "final draft post referee" kann nicht beigebracht werden
AB - 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/Ree, 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.
LB - PUB:(DE-HGF)16
UR - <Go to ISI:>//WOS:000354578700023
DO - DOI:10.1021/acs.langmuir.5b00817
UR - https://juser.fz-juelich.de/record/278935
ER -