Study on preparation and properties of gel polymer electrolytes based on comb-like copolymer matrix of poly(ethylene glycol) monomethylether grafted carboxylated butadiene-acrylonitrile rubber

Abstract

A novel kind of gel polymer electrolytes (GPE) based on comb-like copolymers of poly(ethylene glycol) monomethylether (mPEG) grafted carboxylated butadieneacrylonitrile rubber (XNBR) were prepared by introducing ionic liquids and LiClO 4 into polymer framework. FTIR spectra confirmed the grafting of mPEG to XNBR as side chains, and the content of grafted mPEG were calculated from the integral area of related peaks in 1 H NMR spectra. Such grafted copolymer based GPE with ionic liquids as solvent showed higher ionic conductivity and reached a maximum ionic conductivity of 1.64×10 −3 S/cm (30°C) in the experimental range, because the copolymers performed better polymer chain flexibility, which could be concluded from the decrease of T g and crystallinity through DSC analysis. The generated GPE exhibited high electrochemical stability and the unit cell of LiFePO 4 /GPE/Li could be cycled at room temperature.

Recent Development in Topological Polymer Electrolytes for Rechargeable Lithium Batteries

“…Li et al designed a comb-like GPE based on carboxylated butadiene-acrylonitrile rubber (XNBR), poly(ethylene glycol) monomethylether (mPEG), and ionic liquids (1-butyl-3-methylimidazolium trifluoromethane-sulfonate) (Figure 13d). [116] Compared with traditional polymer matrix, butadiene-acrylonitrile rubber (NBR) with low glass transition temperature (T g ), non-crystallinity, and good elasticity can facilitate tight contact of the interface. Thus, the ionic conductivity of the GPE could achieve a maximum value of 1.64 × 10 −3 S cm −1 at 30 °C, as shown in Figure 13d.…”

“…Copyright 2009, Elsevier B.V. d) Preparation route and schematic structure of GPE; ionic conductivity of GPE based on XNBR, XNBR-mPEG750, and XNBR-mPEG1900 at 30 °C; the second and third circle of cyclic voltammogram with LiFePO 4 /GPE/Li cell using XNBR-mPEG1900/150% LiClO 4 -IL as electrolytes. Reproduced with permission [116]. Copyright 2012, Springer Science Business Media B.V.…”