Facile Access to CO₂‐Sourced Polythiocarbonate Dynamic Networks And Their Potential As Solid‐State Electrolytes For Lithium Metal Batteries

Abstract

Poly(monothiocarbonate)s are an interesting class of sulfurcontaining materials whose application as solid polymer electrolytes was barely studied, certainly due to the elusive production of diversified polymer architectures. Herein, a new liquid CO 2 -sourced bis(α-alkylidene cyclic carbonate) monomer was designed at high yield to allow its one-step and solventfree copolymerization with thiols to produce linear and crosslinked polymers in mild conditions. The influence of the monomer structure on the thermal properties and the ionic conductivity of linear polymers was assessed. The polymer network showed to be thermally re-processable owing to the dynamic nature of the monothiocarbonate bonds. A solid polymer electrolyte was easily obtained from the cross-linked material when combined with LiTFSI salt. The solid polymer electrolyte was characterized by an ionic conductivity reaching 6 × 10 À 6 S cm À 1 at room temperature with a lithium transference number of 0.37 and a wide electrochemical stability window (4.0 V vs Li 0 /Li + ) valid for lithium cycling. This work thus reports an attractive valorizing approach for carbon dioxide to deliver under mild operating conditions poly(monothiocarbonate)containing novel covalent adaptable network materials of high potential for energy applications, especially as solid electrolytes for batteries.

Unprecedented associative exchange in CO2-sourced cyclic S,O-acetal-based covalent adaptable networks

“…with amines, 50,51 with alcohols 52 and thiols. 53 The scope of the obtained polymers was further expanded by different groups to bring more diversification, tunability, functionality, and emerging applications 54–58 without omitting recyclability. 42,59,60…”

Continuous Flow Synthesis of Functional Isocyanate-Free Poly(oxazolidone)s by Step-Growth Polymerization

“…The dehydrated polymer P4 displayed a single mass loss at a T deg10% of 342 °C (Figure c) and two glass transition temperatures at T g,1 = 18 °C and T g,2 = 100 °C (Figures d and S37). The presence of the two T g s was an uncommon feature already observed for other oxazolidone-containing polymers. , They are assumed to originate from two amorphous glassy phases with the hydroxyoxazolidone linkages that are responsible for the high- T g due to increased backbone rigidity and hydrogen bonding.…”

“…The presence of the two T g s was an uncommon feature already observed for other oxazolidone-containing polymers. 19,44 They are assumed to originate from two amorphous glassy phases with the hydroxyoxazolidone linkages that are responsible for the high-T g due to increased backbone rigidity and hydrogen bonding.…”

“…The toxicity of DMF encouraged us to select DMSO as the solvent for the flow process. Our recently reported liquid bisαCCs monomer (LBisαCC, Scheme ), highly soluble in classical organic solvents, was used for this study to ensure better solubility of resulting POxas and avoid clogging …”

“…Our recently reported liquid bisαCCs monomer (LBisαCC, Scheme 1), highly soluble in classical organic solvents, was used for this study to ensure better solubility of resulting POxas and avoid clogging. 44 To estimate the polymerization features and the polymer microstructure prior proceeding to flow conditions, we first investigated the polyaddition of LBisαCC with 3,3′-diamino-N-methyldipropylamine A1 in a traditional batch reactor with magnetic stirring. Experiments were carried out in DMSO using DBU catalyst (5 mol % vs LBisαCC) with a polymerization time of 12 and 24 min to mimic typical residence times in flow set-ups.…”