Highly efficient reversible addition-fragmentation chain-transfer polymerization in ethanol/water via flow chemistry

Abstract

Utilization of a flow reactor under high pressure allows highly efficient polymer synthesis via reversible addition–fragmentation chain‐transfer (RAFT) polymerization in an aqueous system. Compared with the batch reaction, the flow reactor allows the RAFT polymerization to be performed in a high‐efficiency manner at the same temperature. The adjustable pressure of the system allows further elevation of the reaction temperature and hence faster polymerization. Other reaction parameters, such as flow rate and initiator concentration, were also well studied to tune the monomer conversion and the molar mass dispersity (Đ) of the obtained polymers. Gel permeation chromatography, nuclear magnetic resonance (NMR), and Fourier transform infrared spectroscopies (FTIR) were utilized to monitor the polymerization process. With the initiator concentration of 0.15 mmol L−1, polymerization of poly(ethylene glycol) methyl ether methacrylate with monomer conversion of 52% at 100 °C under 73 bar can be achieved within 40 min with narrow molar mass dispersity (D) Đ (<1.25). The strategy developed here provides a method to produce well‐defined polymers via RAFT polymerization with high efficiency in a continuous manner. © 2017 Society of Chemical Industry

Pressure-assisted solvent- and catalyst-free production of well-defined poly(1-vinyl-2-pyrrolidone) for biomedical applications

“…Thus, at some thermodynamic conditions, polymerization is favored and proceeds much faster with respect to the reactions carried out at ambient conditions. 8 Herein one can stress that such results were obtained for the HP controlled ATRP, 9,10 RAFT [11][12][13][14][15] and also FRP. 16,17 Moreover, we have also applied high-pressure to control, 'pseudo-living' RAFT polymerization of sterically hindered imidazolium-based ionic liquids (IL) LAMs.…”

“…2S, ESI †) and SEC analysis. Note that the 1 H and 13 C NMR spectra of PVP, as well as SEC traces for polymers produced by both studied systems (ambient-and high-pressure), are collected in the ESI. † The data for the homopolymerization of VP performed at ambient-pressure are collected in Table 1.…”

Harnessing autocatalytic reactions in polymerization and depolymerization

“…A number of advances have been made in having a desirable control over kinetics of polymerization by using a continuous flow during polymerization. Examples include control over molecular weight (MW) and its distribution in free-radical polymerization, living free-radical polymerization by reversible addition fragmentation chain transfer (RAFT) in ethanol and water [51] as well as diblock copolymerization on grafted polymers [52] (cf. Fig.…”

Effect of Binder Architecture on the Performance of Silicon/Graphite Composite Anodes for Lithium Ion Batteries

“…Glycol chitosan (≥60%-NH 2 by titration, degree of polymerization (DP n ) ≥ 400, see compound 1 in Scheme ), N -(3-(dimethylamino)­propyl)- N ′-ethylcarbodiimide hydrochloride (EDC), 4,4′-azobis­(4-cyanopentanoic acid) (ACPA), lithium hydroxide (LiOH), and N -hydroxysuccinimide (NHS) were obtained from Sigma-Aldrich and used directly. 2-(((Butylthio)­carbonothioyl)­thio)­propanoic acid (compound 2 ) was synthesized following previous literature . Acrylic acid was passed through a column with alternative inhibitor remover and aluminum oxide (basic) to remove any inhibitor before the polymerization.…”

“…Among the polymers with different architectures, − the graft polymers, which are called either combs or bottle brushes depending on grafting density, have been attracting significant attention due to their efficient control over the structure and the corresponding properties of obtained materials. ,− The graft copolymer with chemically distinguished grafted side chains and polymer backbones can retain their desired properties from both polymer components and enable efficient control of both chemical–physical interaction and mechanical performance, , which are extremely important for polymer binder applications. PAA grafted polyvinylidene fluoride (PVDF) and NaPAA grafted CMC are reported to exhibit improved cycling performance compared with linear analogues, while their architecture effect on polymer binder performance was not investigated due to the limitation of synthetic strategy, which did not allow a defined polymer architecture. , Conventional knowledge of “structure–property” relationships in polymers indicates that the structural parameters, such as the side chain length and grafting density, significantly affect the properties of graft polymers. − Another important issue in the real application of typically reported silicon based anode materials is their low mass loading of active materials (usually lower than 0.5 mg/cm 2 ) that renders low areal capacity and energy density despite the high specific capacity. , Utilization of silicon/graphite composite anode materials instead of pure silicon nanoparticles (SiNPs) is one of the solutions to increase the mass loading for practical applications, and this approach is especially popular among the manufacturers because the electrode made of graphite has a mature manufacturing process and relatively low price. − Herein, to elucidate the architecture effect of synthetic polymers on the polymer binder performance for silicon-based anodes, graft block copolymers with well-defined architecture were synthesized by reversible addition–fragmentation chain transfer (RAFT) polymerization − and tested as the polymer binder for the high-mass loading silicon/graphite composite electrode.…”