Dresden 2017 – wissenschaftliches Programm
CPP 51.10: Poster
Mittwoch, 22. März 2017, 18:30–21:00, P3
Annealing in polyelectrolyte multilayers: influence of entanglements — Peter Nestler, Malte Paßvogel, Annkatrin Sill, •Amir Azinfar, and Christiane A. Helm — Inst. of Physics, Greifswald University, Germany
Polyelectrolyte multilayer films were assembled by the layer-by-layer (LbL) technique using poly(stryrene sulfonate) PSS as polyanion and poly (diallyldimethylammonium) (PDADMA) as polycation. The first compartment of the film is built with protonated PSS, the second compartment with deuterated PSSd. The films were annealed in 1 M NaCl and the time dependent intermixing recorded with neutron reflectivity. If the layers are adsorbed from 0.1 M NaCl, the largest diffusion constant is found for Mw(PDADMA) = 45 kDa. If Mw(PDADMA) was lower, so was the diffusion constant. If Mw(PDADMA) was higher, then the diffusion constant dropped by two orders of magnitude. These findings suggest the diffusion of PDADMA/PSS complexes. The largest diffusion constant was obtained if the salt concentration of the preparation solution was decreased (0.03 M, 0.005 M). At low salt concentrations, less polyelectrolyte adsorbs with each deposition step, and fewer entanglements occur. These results suggest that polycation/polyanion complex formation and polymer entanglements influence the diffusion constant within polyelectrolyte multilayers.