Ultrafast SET-LRP in biphasic mixtures of the non-disproportionating solvent acetonitrile with water

Abstract

The two kinetic regime, low conversion and low chain end functionality seen in copper catalyzed polymerization of acrylates in acetonitrile was transformed into a SET-LRP kinetic, to complete conversion and quantitative chain end functionality in a biphasic mixture containing 10% water.

SET-LRP in biphasic mixtures of fluorinated alcohols with water

“…1, 2 and Table 1) in order to maintain comparable conditions with similar experiments performed with acetone/water 36 aceto-nitrile/water 38 and alcohols/water, 41 although a similar trend of the rate of reaction was observed up to solvent/water = 6/4, v/v. 36,38,41 At lower ratios between solvent and water corresponding to less solvent in the reaction mixture the concentration of the solvent becomes too low to maintain a biphasic system 41 and the mechanism of SET-LRP changes from biphasic to triphasic. The second part of this mechanism will be investigated and be reported in different publications.…”

“…[20][21][22][23][24] When biphasic mixtures of TFE and TFP with water were employed, the ratio between TFE and TFP to water was varied from 9/1 to 8/2 and to 7/3 ( Fig. 1, 2 and Table 1) in order to maintain comparable conditions with similar experiments performed with acetone/water 36 aceto-nitrile/water 38 and alcohols/water, 41 although a similar trend of the rate of reaction was observed up to solvent/water = 6/4, v/v. 36,38,41 At lower ratios between solvent and water corresponding to less solvent in the reaction mixture the concentration of the solvent becomes too low to maintain a biphasic system 41 and the mechanism of SET-LRP changes from biphasic to triphasic.…”

“…16,[32][33][34] Our laboratory recently developed a library of "programmed" multiphasic SET-LRP systems based on mixtures of organic solvents with water. [35][36][37][38][39][40][41] Previous experiments that inspired this concept will be discussed in a later subchapter. This approach relies on the unexpected immiscibility between a solution of water containing Cu(II)Br 2 and a ligand with organic solvents, including water miscible organic solvents, containing a monomer and a polymer.…”

“…To support this statement, we reported relevant examples of SET-LRP synthesis of hydrophobic polymers in biphasic aqueous mixtures of non-polar and polar-non-disproportionation solvents. [35][36][37][38] This approach can also be applied to solvents with good disproportionation capabilities such as alcohols as well as dipolar aprotic solvents (i.e. DMSO, sulfolane, NMP, DMAC and DMF).…”

Facile preparation of superhydrophobic and oleophobic surfaces via the combination of Cu(0)‐mediated reversible‐deactivation radical polymerization and click chemistry

“…Since the disproportionation of Cu(I) is the crucial step of SET‐LRP, the solvent dependency of this process is a limitation of the technique. However, the development of multiphase SET‐LRP has expanded the solvent classes that can be used, including less disproportionating solvents, such as acetonitrile and acetone, and even the mixture of ethanol and water with non‐disproportionating solvents, such as hexanes, cyclohexane, ethyl acetate, diethyl carbonate, toluene, and anisole . These improvements together with the intrinsic advantages of the Cu(0)‐mediated RDRP process, such as high reaction rates, tolerance to air, impurities, and radical inhibitors, and near perfect chain‐end fidelity, make it a method of choice for performing surface initiated RDRP reactions …”