Grafted Copolymer Electrolytes Based on the Poly(acrylic acid-co-oligo ethylene glycol acrylate) (P(AA-co-OEGA)) Ion-Conducting and Mechanically Robust Block

Abstract

A series of completely amorphous polymer brushes composed of grafted copolymer electrolytes based on the ioncontaining block of poly(acrylic acid-co-oligo ethylene glycol acrylate) (P(AA-co-OEGA)) doped with LiCF 3 SO 3 (LiTf) or LiN(SO 2 CF 3 ) (LiTFSI) and the glassy polystyrene (PS) block are synthesized and studied with respect to the structural, thermomechanical, and ion conduction properties. The incorporation of some AA units into the ion-conducting phase provides a trade-off between increased mechanical stability and anion/cation complexation. Consequently, the P(AA-co-OEGA) block can be engineered to simultaneously support ion conduction while exhibiting enhanced mechanical stability. Between the two anions ([Tf − ] vs [TFSI − ]), it is the latter that better supports the Li-ion transport. Diblock copolymer electrolytes doped with the larger anion ([TFSI − ]) suppress ion complexation and give rise to superior ion conduction properties (by about 2 orders of magnitude), as compared to that of the smaller anion ([Tf − ]). Overall, the PS-b-P(AA-co-OEGA)/LiTFSI diblock-random copolymer electrolyte with salt concentration, r = 0.08 (r is defined as the molar ratio of Li ions to EO units), best combines the required mechanical stability (storage modulus, G′ ∼ 10 8 Pa) with a relatively high dc-conductivity (σ dc ∼ 10 −6 S•cm −1 ) at an ambient temperature (for application as solid polymer electrolytes (SPEs) in Li-ion batteries). This work suggests routes toward further improving the mechanical stability via the random incorporation of acids into the ion-containing block of nanophase-separated electrolytes.

Control of Lithium Salt Partitioning, Coordination, and Solvation in Vitrimer Electrolytes

“…Characteristic relaxation times do not collapse onto a single universal curve for different linker lengths when plotted as a function of the normalized temperature T g / T , which suggests that their viscoelastic properties are decoupled from segmental dynamics (Figure d). Unlike conventional PEO-based solid electrolytes, − all VU vitrimers preserved their modulus at high temperatures due to a conserved network topology (Figure S9).…”

“…Solid-state electrolytes have been investigated extensively as potentially safer alternatives to flammable and toxic liquid electrolytes − and exhibit good interfacial contact with electrodes. − Poly­(ethylene oxide) (PEO) is a common chemical motif known to facilitate lithium ion transport by ion coordination with the backbone ether oxygens. − Although PEO-based polymer electrolytes show high ionic conductivity, , these materials exhibit relatively low conductivity at room temperature and a strong temperature-dependent modulus that drops substantially upon heating. − To enhance their mechanical properties, PEO can be covalently or noncovalently cross-linked, leading to rubbery electrolytes (characteristic plateau modulus ∼0.1 MPa) with suppressed dendrite formation due to the nanoscale mesh size in cross-linked PEO. ,, However, covalent permanent networks are not easily reprocessed or recycled after the curing processes. In recent years, vitrimers have received increased attention as robust and recyclable solid polymer electrolytes. − Various dynamic bonds such as boronic ester, ,,, imine, − ,, vinylogous urethane, boroxine, and disulfide ,,− have been previously incorporated into vitrimers for solid-state electrolyte applications.…”

Preparation of Crosslinked Poly(acrylic acid-co-acrylamide)-Grafted Deproteinized Natural Rubber/Silica Composites as Coating Materials for Controlled Release of Fertilizer

“…Acrylic acid (AA) and cumene hydroperoxide (CHP) were obtained from Aldrich (St. Louis, MO, USA). The purification of the AA monomer was performed by passing through a column packed with alumina adsorbent before polymerization [ 19 ]. Acrylamide (AM) monomer was obtained from Loba Chemie Pvt.…”

The Effect of Silver Nanoparticles/Titanium Dioxide in Poly(acrylic acid-co-acrylamide)-Modified, Deproteinized, Natural Rubber Composites on Dye Removal

“…Acrylic acid (AA) and cumene hydroperoxide (CHP) were obtained from Aldrich (St. Louis, MO, USA). The AA monomer was purified by passing through a column packed with alumina adsorbent before use [ 21 ]. Tetraethylene pentamine (TEPA) was purchased from Acros Organics (Geel, Belgium).…”