What is the correct reason for different concentration of polyelectrolyte shows different growth behavior of film thickness?

I encountered following:Polyethyleneimine different concentration: 0.5,1.0,1.5,2.0 wt% got linear growing thickness of multilayer when used 1.0 wt%. when used 1.5, 2.0 wt% after 3 layers it starts...

10 March 2017 370 2 View