AGET ATRP of Methyl Methacrylate Based on Thermoregulated Phase Transfer Catalysis in Organic/Aqueous Biphasic System: Facile and Highly Efficient In Situ Catalyst/Ligand Separation and Recycling

Abstract

A novel polymerization system with activators generated by electron transfer for atom transfer radical polymerization (ATRP) for sustainable catalyst/ligand separation and recycling in situ is developed based on thermoregulated phase transfer catalysis in organic/aqueous biphasic system. Herein, a typical iniferter agent 1-cyano-1-methylethyldiethyldithiocarbamte is used as the initiator, and CuBr 2 , monomethoxy poly(ethylene glycol)-350-supported substituted dipicolylamine (L 350 ), ascorbic acid, and methyl methacrylate are employed as the catalyst, thermoresponsive ligand, reducing agent, and the model monomer, respectively. The "living" nature of the system is confi rmed by polymerization kinetics with recycled catalyst complex aqueous solution and chain-extension experiments via iniferter and ATRP mechanism, respectively. In addition, the catalyst residue in polymers is less than 2 ppm and the recycling effi ciency of catalyst complex in water kept more than 95% even after 5 times of recovery experiments while keeping narrow molecular weight distribution ( M w / M n < 1.33).

Atom Transfer Radical Polymerization: Billion Times More Active Catalysts and New Initiation Systems

“…Fluorinated ligands based on PMDETA or bpy were used in normal ATRP in a mixture of perfluoromethyl cyclohexane and toluene at 90 °C . Other thermoregulated catalysts are based on PEG‐supported pyridyl ligands . ICAR ATRP of MMA was conducted in a mixture of toluene and water; at 75 °C: under stirring, enough Br‐Cu II TPMA + deactivator diffused to the organic layer to trigger the polymerization, then, upon cooling, the hydrophilic catalyst diffused to the aqueous layer.…”

Iron-Mediated Homogeneous ICAR ATRP of Methyl Methacrylate under ppm Level Organometallic Catalyst Iron(III) Acetylacetonate

“…Reversible deactivation radical polymerization (RDRP) [1,2,3,4,5,6,7] including initiator-transfer agent-terminator (Iniferter) [8,9,10,11], nitroxide-mediated polymerization (NMP) [12,13,14,15,16,17,18], atom transfer radical polymerization (ATRP) or metal-catalyzed living radical polymerization [19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43] and reversible addition−fragmentation chain transfer polymerization (RAFT) [44,45,46,47,48,49,50,51,52,53,54,55] has been used to design and synthesize various polymeric structure and architectures extensively. Among those methods, ATRP is the most widely used method and has been used to produce different topological polymers, such as star, brush, block and hyperbranched polymers [56,57,58,59].…”

Facilely Recyclable Cu(II) Macrocomplex with Thermoregulated Poly(ionic liquid) Macroligand: Serving as a Highly Efficient Atom Transfer Radical Polymerization Catalyst

“…Theoretically speaking, the used transition metal and ligand can be recycled since they just serve as a catalyst complex in an ATRP process. Till now, there have been some intelligent strategies to separate and recycle the transition metal catalyst from the polymerization systems, which were well summarized by the reviews of our group and others. , For example, we developed a series of methods based on thermoregulated ligands of small organic molecules, such as thermoregulated phase transfer catalysis (TRPTC) ATRP, − diffusion-regulated phase-transfer catalysis (DRPTC) ATRP, and thermoregulated phase separated catalysis (TPSC) ATRP, − to separate and recycle transition metal catalyst in situ . However, these ligands of small organic molecules are easily lost in the separation and recycle process, which results in loss of control over polymerizations or necessary supplement of additional ligands in next recycle experiments.…”