Recent Developments in Atom Transfer Radical Polymerization (ATRP): Methods to Reduce Metal Catalyst Concentrations

Abstract

Atom transfer radical polymerization (ATRP) was initially developed in the mid-1990s, and with continued refinement and use has led to significant discoveries in new materials. However, metal contamination of the polymer product is an issue that has proven detrimental to widespread industrial application of ATRP. The laboratories of K. Matyjaszewski have made significant progress towards removing this impediment, leading the development of "activators regenerated by electron transfer" ATRP (ARGET ATRP) and electrochemically mediated ATRP (eATRP) technologies. These variants of ATRP allow polymers to be produced with great molecular weight and functionality control but at significantly reduced catalyst concentrations, typically at parts per million levels. This Concept examines these polymerizations in terms of their mechanism and outcomes, and is aimed at giving the reader an overview of recent developments in the field of ATRP.

Copper(0)-mediated radical polymerisation in a self-generating biphasic system

“…21 A variety of different routes have been explored to decrease the amount of metallic residues. 5, 22,23 A range of methods has been reported which keeps the catalyst insoluble in the polymerisation phase including the use of fluorous biphase systems, [24][25][26][27] supported catalysts [28][29][30][31] and ionic liquids. [32][33][34][35] A solid supported catalyst can be easily removed, 36,37 but diffusion of reactants to the catalytic site can present a problem.…”

RAFT Polymerization of Monomers with Highly Disparate Reactivities: Use of a Single RAFT Agent and the Synthesis of Poly(styrene-block-vinyl acetate)

“…The success of RAFT polymerization is based on the use of thiocarbonyl thio compounds (normally referred to as RAFT agents) that act as efficient and reversible chain transfer compounds. One of the great advantages that RAFT polymerization has over other reversible-deactivation radical polymerization (RDRP) [10,11] methods, such as nitroxidemediated polymerization (NMP) [12][13][14] and atom transfer radical polymerization (ATRP), [15][16][17][18][19][20] is the breadth of vinyl monomers that can be polymerized using the technique. For example, with judicious choice of RAFT agent a well controlled polymerization (in terms of predictable molecular weights and low dispersities) of activated monomers such as acrylates, methacrylates, and styrenics, or less activated monomers such as vinyl acetate and vinyl esters, can be achieved with relative ease.…”

“Nascent” Cu(0) nanoparticles‐mediated single electron transfer living radical polymerization of acrylonitrile at ambient temperature

“…Atom transfer radical polymerization (ATRP) is an important technique to provide well control over molecular dimension and polymer structure 1–15. To date, two promising techniques are activators regenerated by electron transfer (ARGET) ATRP and initiators for continuous activator regeneration (ICAR) ATRP as they can allow for a substantial reduction in the amount of metal catalyst required (usually ca.…”