Poly(phosphazene−ethylene oxide) Di- and Triblock Copolymers as Solid Polymer Electrolytes

Abstract

The synthesis of polyphosphazene-co-poly(ethylene oxide) block copolymers with well-defined molecular weights has been accomplished via end-functionalized polymer intermediates. Mono-and diamine-terminated poly(ethylene oxides) (PEO ) (CH 2CH2O)n-CH2CH2-) were used to produce polymerbased phosphoranimines, CH3O-(CH2CH2O)n-CH2CH2-NH(CF3CH2O)2PdNSiMe3 and Me3SiNdP(OCH2-CF3)NH-(CH2CH2O)n-CH2CH2-NH(CF3CH2O)2PdNSiMe3. These were then converted to macroinitiators via reaction with PCl5 to produce CH3O-PEO-NH[(CF3CH2O)2PdNPCl3] + [PCl6]and [Cl3PNdP(OCH2-CF3)NH-PEO-NH[(CF3CH2O)2PdNPCl3] 2+[PCl6]2 -, respectively. These macroinitiators were used to polymerize Cl3PdNSiMe3 in a living manner to produce diblock copolymers of polyphosphazenes with poly(ethylene oxide) or triblock copolymers with poly(ethylene oxide) blocks flanked by polyphosphazene components. In addition, the monophosphoranimine-terminated PEO was employed as a terminator in the living, cationic polymerization of Cl3PdNSiMe3 to produce triblock copolymers with a polyphosphazene block flanked by two poly(ethylene oxide) blocks. Polymers for use as solid-ionic conduction media or hydrogels were produced by nucleophilic replacement of the chlorine atoms along the polyphosphazene segments by methoxyethoxyethoxy units. The ionic conductivities of these materials, after complexation with varying ratios of lithium triflate, ranged from 7.6 × 10 -6 to 1.0 × 10 -4 S cm -1 for a temperature range of 20-80 °C.

Recent Research Progress in the Synthesis of Polyphosphazene and Their Applications

“…By this method, polyphosphazene block co-polymers are synthesized conveniently and polyphosphazenes are produced with wide range of different macromolecule block structures; for example, polyphosphazene-block-polyphosphazene copolymers [5], poly(ethylene oxide)-block-polyphosphazene co-polymers [36,37] and polystyrene-block polymer phosphazene co-polymers [38,39]. These polymers are utilized for biomedical applications.…”

Silicon-Containing Carbonates—Synthesis, Characterization, and Additive Effects for Silicon-Based Polymer Electrolytes

“…Over the past three decades, ion-conducting polymers have been investigated as promising and safe alternatives to the commercially available electrolytes currently used in lithium batteries [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. The initial discoveries that polymer complexes could be used as either liquid [1] or solid [2] ionic conductors has led to the development of a wide range of polymer-based electrolytes.…”

“…However, PEO is crystalline at room temperature and can be electrochemically unstable. Therefore, efforts have focused on the combination of PEO with amorphous polymers such as polyphosphazenes [3][4][5][6][7][8] and polysiloxanes [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] via copolymerization reactions.…”

“…Although significant research has concentrated on the development of polysiloxane-PEO copolymer structures, alternative polymer electrolytes structures have also been investigated [3][4][5][6][7][8][27][28][29]. For example, Wnek and coworkers [27] introduced carbonate groups onto the polysiloxane backbone in order to study them as potential polymer electrolytes.…”

Synthesis and Self-Assembly of Condensation Polymer Architectures

“…Furthermore, the polymers self-assembled in a unique way. KEY WORDS Self-Assembly / Polymer Architectures / Chain-Growth Condensation Polymerization / Aromatic Polyamide / Aromatic Polyether / (Received June 25, 2007: Accepted September 10,2007) [ Kobunshi Ronbunshu, 64(12), 907-921 (2007)]…”