Study of the concentration dependence of the depletion length of free polymer inhighly concentrated microgel dispersions
The major part of the huge re-entry region of microgel colloids in mixtures with free polymer is located at effective polymer concentrations cP,Vfree above the overlap concentration. This suggests that the concept of the radius of gyration Rg becomes obsolete in semi-dilute polymer solutions and should be replaced by the screening length xs. Thus the depletion length should be defined by d=xs/Rcolloid and as xs<Rg the depletion length should decrease when entering the semi-dilute regime in the phase diagram. This could explain the large re-entry region in microgel-polymer-mixtures as compared to other systems with the same apparent depletion length. The extension of the fluid pocket increases significantly with a decrease of d as predicted by theory and verified in recent experiments. To obtain a complete picture of the size and the arrangement of the free PS polymer in the colloid-polymer mixture at different concentrations it is neccesary to determine the screening length xs and the structure factor of the free polymer. In addition the complementary structure factor of the microgel particles is also needed. To achieve the required q-range and resolution use of D11 is requested.
Please note that you will need to login with your ILL credentials to download the data.
Download DataThe recommended format for citing this dataset in a research publication is in the following format:
WERNER Marcel; BARTSCH Eckhard; GISIN Joshua and LINDNER Peter. (2016). Study of the concentration dependence of the depletion length of free polymer inhighly concentrated microgel dispersions. Institut Laue-Langevin (ILL) doi:10.5291/ILL-DATA.9-12-475
ILL has partnered with DataCite as the registration agency
for data persistent identifiers.