Grafting PMMA onto P(VDF‐TrFE) by CF Activation via a Cu(0) Mediated Controlled Radical Polymerization Process

Abstract

In the present work, poly(methyl methacrylate) (PMMA) is successfully grafted onto poly(vinylidene fluoride‐trifluoroethylene) (P(VDF‐TrFE)) side chains via directly activated CF bonds using Cu(0)/2,2′‐bipyridine as catalyst. The reaction mechanism and the initiating sites can be confirmed by the structure of the graft copolymer. The graft copolymerization exhibits first‐order kinetics, and reaction conditions can affect the chemical composition of the graft copolymer, including reaction time, reaction temperature, solvents, the amount of catalyst, and monomer. The introduction of rigid PMMA side chains onto P(VDF‐TrFE) can effectively tune the displacement–electric field hysteresis behaviors of P(VDF‐TrFE) from normal ferroelectric to anti‐ferroelectric, even linear‐like dielectric, under high electric field, resulting in dramatically reduced energy loss while maintaining the discharged energy density. This work may provide an effective strategy to introduce functional groups into P(VDF‐TrFE) copolymer via activation of CF bonds.

Grafting Modification of Poly(vinylidene fluoride‐trifluoroethylene) via Visible‐Light Mediated C–F Bond Activation

“…More importantly, no double bond (–CF 2 C H = C H CF 2 –) characteristic peaks are observed in the 1 H NMR spectrum of the resulting graft copolymer, indicating that the dehydrofluorination reaction ( β ‐H elimination) is effectively avoided in the current photocatalytic system, which occurs in the Cu(0)‐mediated SET‐CRP process. [ 22,23 ] Therefore, the composition of h‐P(VDF‐TrFE)‐ g ‐PMMA referring to the molar ratio of VDF, TrFE, and MMA units can be estimated according to formula (1), $$\begin{eqnarray}{\rm{VDF/TrFE/MMA}} = 80/20/\left(\frac{2}{3} \times \frac{{{I_4}}}{{{I_1} + {I_2}}} \times 80\right){\rm{ }}\end{eqnarray}$$…”

“…As previously reported, the inevitable homo‐polymerization of MMA can compete with the graft polymerization initiated from h‐P(VDF‐TrFE). [ 37 ] Although the content of grafted MMA is relatively low compared with the Cu(0)‐mediated SET‐CRP method, [ 22 ] this photocatalytic system effectively avoids the side reaction of dehydrofluorination. On the other hand, due to the extremely low catalyst content, the purification process is greatly simplified.…”

A Novel Aminomethacrylate-Based Copolymer for Solubility Enhancement—From Radical Polymer Synthesis to Manufacture and Characterization of Amorphous Solid Dispersions

“…The impact of CTAs on the average M w of a (co-)polymer to be synthesized is concentration dependent and the M w of the resulting (co-)polymer typically decreases with increasing CTA concentration. Regardless of whether a CTA is added or not, it is desirable to achieve a high monomer conversion by choosing suitable reaction conditions for the polymerization process, which at the same time promises a very low number of residual monomers [ 18 ]. Altogether, this would not only increase the yield, but also reduce the time required for the purification of the (co-)polymer.…”

“…Altogether, this would not only increase the yield, but also reduce the time required for the purification of the (co-)polymer. By means of a robust synthesis method, (co-)polymers which reflect the mass ratio of the monomers used, and consequently also the ratio of their functional units, can be obtained in a reproducible way [ 18 ].…”

In-Situ Synchrotron SAXS and WAXS Investigation on the Deformation of Single and Coaxial Electrospun P(VDF-TrFE)-Based Nanofibers

“…The most commonly used PVDF-based terpolymer is poly(vinylidene fluoride-trifluoroethylene-chlorotrifluoroethylene), denoted as P(VDF-TrFE-CTFE). When producing a relaxor-based ferroelectric polymer, the third monomer, chlorotrifluoroethylene (CTFE), is inserted in the P(VDF-TrFE) copolymer chain to compose the terpolymer, P(VDF-TrFE-CTFE) [ 34 ]. P(VDF-TrFE-CTFE) owns a narrow hysteresis loop, higher polarization, higher dielectric constant, higher electrostriction, and higher electromechanical response [ 35 , 36 ].…”