Synthesis and Characterization of Poly(acrylic acid) Brushes: “Grafting‐Onto” Route

Abstract

A guideline for the synthesis of poly(acrylic acid) brushes on planar silica surfaces by the "grafting-onto" approach is described. It is demonstrated that some thermal precautions must be taken to obtain extended brushes. It is also shown that neutron refl ectivity is well suited for the characterization of each step of the synthesis, while it is (unfortunately) rarely used for that purpose. The steps are the following: fi rst, the substrates are covered with a self-assembled monolayer of epoxy-terminated molecules; then, the poly( tert -butyl acrylate) brushes are built using preformed and end-functionalized chains; fi nally, the deprotection of the ester group is performed using a pyrolysis reaction to convert the poly( tert -butyl acrylate) brushes into poly(acrylic acid) brushes.

pH‐Responsive Swelling of Poly(acrylic acid) Brushes Synthesized by the Grafting Onto Route

“…It allows the cover of the GPS silane molecules, which are not connected to long chains to neutralize epoxy functions. It was shown that this additional step allows the achievement of “real” polymer brushes by preventing from the formation of loops . The brush with dry thickness of 50 Å has swollen thicknesses of 93 Å at pH 2 and 120 Å at pH 9.…”

“…The PAA brushes were synthesized by following the “grafting onto” strategy, as already published here . In a first step, the self‐assembled monolayer of GPS was grafted on silicon wafers by immersing the freshly cleaned Si wafers in a 2 vol% GPS solution in anhydrous toluene for 5 h. Then, a P t BuA reservoir was spread on the surface by spin‐coating from 1 wt% THF solution.…”

“…In this paper, we report the swelling behavior of PAA brushes. The brushes are synthesized on silicon wafers using the “grafting onto” route as reported in a previous paper . We study the stretching of the brushes in aqueous solutions at different pH using neutron reflectivity and we determine their density profile.…”

“…The brushes are synthesized on silicon wafers using the "grafting onto" route as reported in a previous paper. [ 23 ] We study the stretching of the brushes in aqueous solutions at different pH using neutron refl ectivity and we determine their density profi le. We compare the experimental density profi les with the analytical forms from self-consistent fi eld calculations.…”

Synthesis of naringin‐based polymer brushes via seATRP

“…These polymerization methods include ring‐opening polymerization, click reaction, cationic polymerization, anionic polymerization, radical (co)polymerization, reversible addition‐fragmentation chain transfer polymerization (RAFT), nitroxide‐mediated polymerization (NMP), and atom transfer radical polymerization (ATRP), as well as combinations of different methods . Considering these techniques, macromolecular brushes can be synthesized via three main approaches: “grafting through”, “grafting onto”, or “grafting from” . Undoubtedly, “grafting from” is one of the most useful technique which involves attachment of initiator molecules to the backbone and growing of polymer chains via polymerization; therefore, macromolecular brushes with high grafting density can be prepared by using these tactics …”