13483-49-3Relevant academic research and scientific papers
Alternating copolymers of carbon dioxide with glycidyl ethers for novel ion-conductive polymer electrolytes
Tominaga, Yoichi,Shimomura, Tomoki,Nakamura, Mizuki
, p. 4295 - 4298 (2010)
To overcome the low ionic conduction of existing poly(ethylene oxide)-based polymer electrolytes, we consider polycarbonates obtained from the copolymerization of CO2 and epoxy monomers. We synthesized four types of polycarbonates possessing phenyl, n-butyl, t-butyl and methoxyethyl side groups using zinc glutarate, and measured the ionic conductivity of their electrolytes, including 10 mol% of LiTFSI. The electrolyte possessing methoxyethyl side groups had the highest conductivity, of the order of 10-6 S cm-1 at room temperature. The activation energy (Ea) for ionic conduction in the polycarbonate electrolytes was estimated from the VTF equation, and the Ea of the electrolyte possessing n-butyl side groups was almost the same with the polyether-based electrolytes. An interesting feature of our study is that the polycarbonate is a unique candidate for ion-conductive polymers because of its flexible and hydrophobic properties.
Synthesis of neutral, water-soluble oligo-ethylene glycol-containing dendronized homo-and copolymers of generations 1, 1.5, 2, and 3
Sun, Xiaoyu,Lindner, Jean-Pierre,Bruchmann, Bernd,Schlüter, A. Dieter
, p. 7337 - 7346 (2014)
Oligo-ethylene glycol-containing dendronized monomers MG1, MG1.5, MG2, and MG3 were synthesized in a particularly easy fashion on the gram scale involving only few steps. Their corresponding homopolymers (PG1, PG1.5, PG2, and PG3) and copolymers (PG1co2, PG1co3, and PG2co3) were synthesized via free radical polymerization. All the polymers are soluble in water and also in organic solvents such as DCM, CHCl3, 1,4-dioxolane, DMF, and DMSO. Their glass transition temperatures (Tg) are in the range -68 °C g -48°C and thus rather low. All polymers show thermoresponsive behavior which was investigated by turbidity measurements. Interestingly, a 1:1 mixture of homopolymers PG1 and PG2 behaves identical with PG1 alone, while the collapse curve of copolymer PG1co2 is almost superimposable with that of PG2 alone. Thus, in the former case PG1 dominates the thermoresponsive behavior while in the latter this is done by the G2-dendrons in the copolymer. Finally, the polymer chains were visualized by AFM, confirming the rod-like behavior of these rigidified polymers.
Effect of oxyethylene side chains on ion-conductive properties of polycarbonate-based electrolytes
Morioka, Takashi,Ota, Keisuke,Tominaga, Yoichi
, p. 21 - 26 (2016)
We have synthesized polycarbonates having oxyethylene (OE) end groups from alternating copolymerization of CO2 with glycidyl ether monomers, and studied the effect of OE length on the ion-conductive properties of electrolytes with lithium bis-(fluorosulfonyl) imide (LiFSI). Polycarbonate-based electrolytes exhibited obvious dependence of the ion-conductive behavior on the salt concentration; the conductivity of PEtGEC (polycarbonate possessing ethoxy side groups) electrolyte increased with increasing salt concentration, and the conductivity of PME1C (polycarbonate possessing 2-methoxyethoxy side groups) and PME2C (polycarbonate possessing 2-(2-methoxy)ethoxy side groups) electrolytes decreased at low salt concentration but then increased dramatically with increasing concentration. PME2C-LiFSI (376 mol%) had the greatest conductivity of all the electrolytes. We also measured the Li transference numbers (tLi+) of polycarbonate-based electrolytes; the values of tLi+ for LiFSI electrolytes (188 mol%) decreased with increasing number of OE chains. This indicates that dissociated Li ions are trapped and that migration is inhibited by the OE side groups. For the PEtGEC electrolyte, tLi+ was very high, more than 0.7, because the polymer has only one ether oxygen atom in the side chain, making it difficult to form stable solvation structures. This study suggests a new polymer matrix combining ether units to give high conductivity at low salt concentrations with a carbonate main chain for high tLi+.
Synthesis and structure–activity relationships of nonionic surfactants with short fluorocarbon chains
Wang, Ruiguo,Song, Lingyun,Guo, Yuanqiang,Kou, Junjie,Song, Hongjian,Liu, Yuxiu,Zhang, Jingjing,Wang, Qingmin
, (2020/10/20)
The biodegradability of fluorinated surfactants can be improved by reducing the length of the fluorocarbon chain. In this study, ten new nonionic fluorinated surfactants with various hydrophilic and hydrophobic chain lengths were synthesized by means of s
Enhancement of Cation Binding in Lariat Ethers Bearing a Methyl Group at the Quaternary, Pivot Carbon Atom
Nakatsuji, Yohji,Nakamura, Tetsuya,Okahara, Mitsuo,Dishong, Dennis M.,Gokel, George W.
, p. 1237 - 1242 (2007/10/02)
A number of carbon-pivot lariat ethers have been prepared and compared, with their counterparts having a methyl group bonded to the side-arm-bearing or pivot carbon.All of the compounds examined are 15-crown-5 derivatives, and in this series, the methyl lariats invariably show a higher affinity for sodium than do the nonmethylated species.The results are less consistent in the case of potassium cation which is larger than the 15-crown-5 compound's cation binding hole.The enhanced stability constant observed for sodium with the methyl lariats is attributed to reduced s ide-arm mobility or conformational changes in either the side arm or macroring.
Crown Cation Complex Effects. 20. Syntheses and Cation Binding Properties of Carbon-Pivot Lariat Ethers
Dishong, Dennis M.,Diamond, Craig J.,Cinoman, Michael I.,Gokel, Geoge W.
, p. 586 - 593 (2007/10/02)
In an effort devise synthetic cation binders that will mimic the behavior of naturally occuring ionophores such as valinomycin, we have prepared approximately 30 macrocyclic (crown) polyethers bearing flexible side chains attached to the macro ring at carbon.In many of these "carbon-pivot" compounds, the side chain contains one or more neutral donor groups that, if in a suitable geometrical arrangement, may provide additional solvation to the macro-ring-bound cation.Although such donors often enhanced the cation binding ability, overall, the increases in stability constants were modest.The physical resemblance and concept of "roping and tying" the cation suggest the name "lariat ethers".Syntheses of these molecules and binding by them of Na+ and K+ cations are reported and conclusions drawn about the structural requirements and cation binding efficacy of these materials.
