We report on the rapid formation of charge density gradients in polymer films by exposing poly([2-dimethylaminoethyl] methacrylate) (PDMAEMA) films resting on flat silica substrates to methyl iodide (i.e., MI, also known as iodomethane) vapors. We adjust the charge gradient by varying the MI concentration in solution and the process time. The thickness of the parent PDMAEMA film does not affect the diffusion of MI through and the reaction kinetics in the films. Instead, the diffusion of MI through the gaseous phase constitutes the limiting step in the overall process.
This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS macro letters, copyright c American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/doi/10.1021/acsmacrolett.9b00930.