Synthesis of block copolymers by atom transfer radical polymerization oftert-butyl acrylate with poly(oxyethylene) macroinitiators

Abstract

SUMMARY: Poly(oxyethylene)s terminated at both ends with 2-bromopropionate end-groups were prepared and characterized by means of MALDI TOF mass spectrometry. It was shown, that atom transfer radical polymerization (ATRP) of methyl methacrylate with a poly(oxyethylene) macroinitiator in bulk proceeds with low initiation efficiency while polymerization of tert-butyl acrylate proceeds with practically quantitative initiation, leading to ABA block copolymers. Originally formed tert-butyl acrylate blocks contain terminal bromine, as expected for the ATRP mechanism. MALDI TOF analysis indicates, however, that in the later stages of polymerization side reactions lead to elimination of terminal bromine.

Double-Hydrophilic Block Copolymers: Synthesis and Application as Novel Surfactants and Crystal Growth Modifiers

“…ATRP of tert-butyl acrylate with a PEO macroinitiator was also described using CuBr as the catalyst and pentamethyldiethylenetriamine as a complexing agent. [63] The block copolymer was obtained in high yields (A 80%) and rather narrow polydispersity (a1.35). Although PEO, which had been reacted with 2-bromopropionyl bromide, was used as a macroinitiator, thus leading to ABA block copolymers, the synthesis could be modified for the preparation of AB block copolymers by just using monomethoxy-PEO, as described in the literature.…”

Atom-Transfer Radical Polymerization of Acrylates in an Ionic Liquid

“…[15,16] The analysis of the isotope distribution of signals of the minor series (m/z = 1 404, 1 532) indicates the presence of two species differing by two molar mass units and, thus, giving partly overlapping signals. Neither of these species contains bromine.…”

“…It therefore seems that, in addition to disproportionation, there is another process by which the macromolecules containing the saturated end groups may be formed, as suggested in our previous paper. [16] The extent of this sidereaction is much less than in bulk polymerizations studied previously under similar conditions. [16] This is shown in Figure 5, where the fractions of macromolecules containing terminal C1Br groups (i. e. potentially active macromolecules) at different stages of polymerization are compared for polymerization in bulk and in IL.…”

Low-fluorinated homopolymer from heterogeneous ATRP of 2,2,2-trifluoroethyl methacrylate mediated by copper complex with nitrogen-based ligand

“…However, for PMDETA system as shown in Fig. 5, the curved plot demonstrates that the radical concentration is continuously decreased during the polymerization reactions because of continuous consumption of monomer, irreversible termination of radical-radical coupling or a side reaction involving a radical transfer from the propagating chain to the ligand species to form nonpropagatable (dead) chains, as has been proposed by other research groups [63,64].…”