Synthesis and ionic conductivity of siloxane based polymer electrolytes with pendant propyl acetoacetate groups

Abstract

Hydrosilylation reaction of 2.4.6.8-tetrahydro-2.4.6.8-tetramethylcyclotetrasiloxane (D4H) with allyl acetoacetate at 1:4.1 molar ratios of initial compounds in the presence of platinum hydrochloric acid (0.1 M solution in THF), Karstedt’s catalyst (Pt2[(VinSiMe2)2O]3) and platinum on the carbon have been carried out and D4R type compounds obtained. Reaction order, rate constants and activation energies for hydrosilylation reactions in the presence of Karstedt’s catalyst have been determined. Ring-opening polymerization reaction of D4R in the presence of catalytic amounts of powder-like potassium hydroxide has been carried out. A linear methylsiloxane oligomer with regular arrangement of propyl acetoacetate groups in the side chain has been obtained. The synthesized methylorganocyclotetrasiloxane and oligomers were studied by FTIR, 1H, 13C and 29Si NMR spectroscopy. Comb-type oligomers were characterized by gel-permeation chromatography, wide-angle X-ray diffractometry and differential scanning calorimetry. Solid oligomer electrolyte membranes have been obtained via sol–gel processes involving lithium trifluoromethylsulfonate (triflate) or lithium bis(trifluoromethylsulfonyl)imide. The specific volumetric electrical conductivity of the membranes at room temperature covers a wide range, from 10−10 to 10−4 S · cm−1, and depends on the structures of grafted anion receptors and the polymer backbones. Higher values of the specific conductivity are seen for the membranes containing triflate.

Ring-Opening Polymerization (ROP) and Catalytic Rearrangement as a Way to Obtain Siloxane Mono- and Telechelics, as Well as Well-Organized Branching Centers: History and Prospects

“…Further, the reaction of compounds containing epoxy groups with primary and secondary amines was carried out, and the corresponding compounds containing aminohydroxyl groups were obtained. Similarly, a linear methylsiloxane oligomer with regular arrangement of propyl acetoacetate groups in the side chain has been obtained [149]. In this work, the possibility of revealing epoxy groups is open to question; however, the authors confirm the composition and structure of the obtained compounds according to elemental analysis, such as FTIR, and 1 H, 13 C, and 29 Si NMR spectrum.…”

Organosilicon‐Based Functional Electrolytes for High‐Performance Lithium Batteries

“…Siloxanes can not only serve as solvents but also as electrolyte additives which could participate in the interfacial film forming processes at both cathode and anode surfaces. [ 80–83 ] It was reported that the thermal stability of cathode charged in the siloxane electrolyte was superior to that in the carbonate‐based electrolyte. [ 84 ] Siloxane electrolytes were also demonstrated particularly suitable for carbonaceous electrode materials by forming a passive film at the electrode/electrolyte interface.…”

Comb-type fluorine-containing polymer electrolyte membranes

“…Thus, polyorganosiloxanes with a regular arrangement of the side donor groups can be obtained. 11,12 As expected, the properties of the comb-type organosilicon polymers depend on the structure of macromolecular chains and on the nature of the organic groups surrounding the silicon atom. 8 In the comb-type copolymers, there are organic substituent groups of different sizes and types bonded to the methylsiloxane hydrophobic matrix.…”

“…overlaps with the signals of methine groups, 3.8 (m, Si-O-CH 2 ), 4.5 (t, CH 2 -CF 2 ), 5.95-5.61 (t, CF 2 H). 13 12,14,15 The hydrosilylation reactions in the presence of other catalysts were carried out in accordance with the same method.…”