%0 Journal Article %1 doi:10.1063/1.2812564 %A Foster, Tobias %A Sottmann, Thomas %A Schweins, Ralf %A Strey, Reinhard %D 2008 %J The Journal of Chemical Physics %K Sottmann from:mkrappel %N 6 %P 064902 %R 10.1063/1.2812564 %T Small-angle-neutron-scattering from giant water-in-oil microemulsion droplets. II. Polymer-decorated droplets in a quaternary system %U https://doi.org/10.1063/1.2812564 %V 128 %X Amphiphilic block copolymers of the type poly(ethylenepropylene)-co-poly(ethyleneoxide) dramatically enhance the solubilisation efficiency of non-ionic surfactants in microemulsions that contain equal volumes of water in oil. Consequently, the length scale of the microstructure of such bicontinuous microemulsions is dramatically increased up to the order of a few 100nm. In this paper, we show that this so-called efficiency boosting effect can also be applied to water-in-oil microemulsions with droplet microstructure. Such giant water-in-oil microemulsions would provide confined compartments in which chemical reactions of biological macromolecules can be performed on a single molecule level. With this motivation we investigated the phase behavior and the microstructure of oil-rich microemulsions containing D2O, n-decane(d22), C10E4 and the amphiphilic block copolymer PEP5-PEO5 poly(ethylenepropylene)-co-poly(ethyleneoxide), weight per block of 5000g∕mol. We found that 15wt% of water can be solubilised by 5wt% of surfactant and block copolymer when about 6wt% of surfactant is replaced by the block copolymer. Small-angle-neutron-scattering experiments were performed to determine the length scales and microstructure topologies of the oil-rich microemulsions. To analyze the scattering data, we derived a novel form factor that also takes into account the scattering contribution of the hydrophobic part of the block copolymer molecules that reside in the surfactant shell. The quantitative analysis of the scattering data with this form factor shows that the radius of the largest droplets amounts up to 30nm. The novel form factor also yielded qualitative information on the stretching of the polymer chains in dependence on the polymer surface density and the droplet radius

@article{doi:10.1063/1.2812564, abstract = {Amphiphilic block copolymers of the type poly(ethylenepropylene)-co-poly(ethyleneoxide) dramatically enhance the solubilisation efficiency of non-ionic surfactants in microemulsions that contain equal volumes of water in oil. Consequently, the length scale of the microstructure of such bicontinuous microemulsions is dramatically increased up to the order of a few 100nm. In this paper, we show that this so-called efficiency boosting effect can also be applied to water-in-oil microemulsions with droplet microstructure. Such giant water-in-oil microemulsions would provide confined compartments in which chemical reactions of biological macromolecules can be performed on a single molecule level. With this motivation we investigated the phase behavior and the microstructure of oil-rich microemulsions containing D2O, n-decane(d22), C10E4 and the amphiphilic block copolymer PEP5-PEO5 [poly(ethylenepropylene)-co-poly(ethyleneoxide), weight per block of 5000g∕mol]. We found that 15wt% of water can be solubilised by 5wt% of surfactant and block copolymer when about 6wt% of surfactant is replaced by the block copolymer. Small-angle-neutron-scattering experiments were performed to determine the length scales and microstructure topologies of the oil-rich microemulsions. To analyze the scattering data, we derived a novel form factor that also takes into account the scattering contribution of the hydrophobic part of the block copolymer molecules that reside in the surfactant shell. The quantitative analysis of the scattering data with this form factor shows that the radius of the largest droplets amounts up to 30nm. The novel form factor also yielded qualitative information on the stretching of the polymer chains in dependence on the polymer surface density and the droplet radius}, added-at = {2020-08-03T08:28:46.000+0200}, author = {Foster, Tobias and Sottmann, Thomas and Schweins, Ralf and Strey, Reinhard}, biburl = {https://puma.ub.uni-stuttgart.de/bibtex/20c2ec2246c7184e783f8b33ac7b92525/ak_sottmann}, doi = {10.1063/1.2812564}, eprint = {https://doi.org/10.1063/1.2812564}, interhash = {7bc82f09d0a5bf4ccfeca70cf165392d}, intrahash = {0c2ec2246c7184e783f8b33ac7b92525}, journal = {The Journal of Chemical Physics}, keywords = {Sottmann from:mkrappel}, number = 6, pages = 064902, timestamp = {2020-08-03T06:28:46.000+0200}, title = {Small-angle-neutron-scattering from giant water-in-oil microemulsion droplets. II. Polymer-decorated droplets in a quaternary system}, url = {https://doi.org/10.1063/1.2812564 }, volume = 128, year = 2008 }