Cu-Mediated Butadiene ATRP

Abstract

Despite over two decades of research, butadiene (BD) remains one of the most challenging monomers for atom transfer radical polymerization (ATRP). A comprehensive mechanistic investigation of the effect of the reaction parameters (initiator structure, halide, Cu catalyst, ligand, solvent, temperature, reagent ratios, ATRP method, etc.) on the polymerization outcome (kinetics, dependence of the molecular weight (M n ), polydispersity (PDI), and halide chain end functionality (CEF) on conversion) affords a quantitative understanding of diene ATRP and reveals that despite drawbacks such as low boiling point, Diels−Alder dimerization, a very low polymerization rate, and especially, a very weak and side-reaction-prone allyl halide chain end, a rational selection of the polymerization conditions (normal-or ICAR (initiators for continuous activator regeneration)-ATRP, tertiary bromoester initiators, low nucleophilicity ligands including bipyridyl, nonpolar solvents such as toluene at 110−130 °C), still enables the synthesis of welldefined polybutadiene (PBD) with a wide range of M n values (1000−100000), low PDIs (1.3−1.5) and high Br-CEFs (>90%), suitable for the synthesis of complex architectures including star PBD and ABA triblock copolymers with styrene and methyl methacrylate.

Imine‐based covalent organic framework as photocatalyst for visible‐light‐induced atom transfer radical polymerization

“…Atom transfer radical polymerization (ATRP) is a powerful technique for preparing well-defined polymers, [1][2][3] which requires external stimulus to achieve controllability. The possible external stimulus include temperature, 4,5 pH, 6,7 light, [8][9][10] electrochemistry, 11 ultrasound, 12 and others. Particularly, due to the excessive consumption of fossil fuel energy, the utilization of clean and green light energy has attracted much more attention.…”

Radical polymerization of butadiene mediated by molecular iodine: a kinetic study of solution homopolymerization

“…The industrial production of diene-based homo-and copolymers is estimated to be billions of pounds annually [1,2]. 1,3-Butadiene (Bu), isoprene (Ip), and chloroprene (Cp) are the most important conjugated 1,3-diene monomers.…”

“…Statistical copolymers of Bu with comonomers such as styrene and acrylonitrile (AN) are synthesised by radical emulsion polymerization. Corresponding copolymers are used in various fields such as production of tires, rubbers, adhesives, coatings and high impact materials [1,2]. On the other hand, corresponding block copolymers with a thermoplastic elastomeric characteristics are synthesized by sensitive and expensive anionic/ coordination polymerizations under strict conditions [1,3,4].…”

“…free radical telomerization, as well as by expensive (living) anionic polymerizations [7][8][9]. However, alternative polymerization methods based on low-cost, applicable in green water/ emulsion medium, reversible-deactivation radical polymerizations (RDRPs) are preferred due to a linear dependence of molecular weight M n on the conversion, low dispersity index ( D ), and high chain-end functionality suitable for synthesis of (multi)block or other condensation polymer architectures [1,10,11]. Equilibrium process of reversible termination (e.g.…”

“…Equilibrium process of reversible termination (e.g. nitroxide-mediated polymerization (NMP) [12] and atom transfer radical polymerization (ATRP) [1,13,14]) or reversible transfer (e.g. reversible addition-fragmentation chain transfer polymerization (RAFT) [15,16] and (reverse) iodine transfer radical polymerization ((R)ITP) [17][18][19][20][21] is basis of these methods.…”