Ethyl Glycidyl Ether Research Articles

Study on the initiation step of 2-(9-carbazolyl)ethyl glycidyl ether polymerization by K −, K + (15-crown-5) 2

Several reactions occur during the initiation of 2-(9-carbazolyl)ethyl glycidyl ether polymerization by K −, K + (15-crown-5) 2. At first the oxirane ring is opened mainly in the β-position. An organometallic intermediate obtained cleaved then the linear ether bond in the substituent and the cyclic one in crown ether. Various potassium alkoxides are finally formed. They are the real initiators of the polymerization. 9-Vinylcarbazole being another reaction product is inactive in this process.

Polymer electrolytes derived from dendritic polyether macromonomers

To develop highly conducting polymer electrolytes, dendritic polyether macromonomers were synthesized, and new network polymer electrolytes were prepared by photo-cross-linking reaction of the macromonomers with a dissolved lithium salt. The macromonomers were synthesized by the anionic ring-opening copolymerization of ethylene oxide (EO) and 2-(2-methoxyethoxy)ethyl glycidyl ether (MEEGE) in the presence of diglycerin as a starting material to yield dendritic polyether tetra-ol, followed by the partial methoxyethylation of the terminal hydroxyl groups and successive acrylation of the residual hydroxyl groups. Ionic conductivity of the polymer electrolytes was dependent on the molecular weight and the extent of methoxyethylation of the macromonomers and reached 10 −4 S cm −1 at 30°C. The introduction of hyper-branched side chains into the network polymer electrolytes by using the dendritic macromonomers was effective for increasing the ionic conductivity.

High molecular weight functionalized poly(ethylene oxide)

Novel high molecular weight copolymers of ethylene oxide (EO) and glycidol or ethoxy ethyl glycidyl ether (EEGE) were obtained via suspension anionic coordination polymerization using calcium amide-alkoxide initiating system. 1H and 13C NMR spectroscopy were used for the structural characterization of the copolymers as well as for the determination of the molar content (up to 2 mol%) of the functional monomers incorporated into the PEO backbone. SEC measurements of the copolymers determined M ̄ n in the range of (2–11)×10 5 g/mol. Surprisingly low polydispersity values of average M ̄ w / M ̄ n =1.5 were obtained for the EO/EEGE copolymers. The calcium amide-alkoxide initiated polymerization of EEGE resulted in high molecular weight polymers with relatively broad polydispersity values ( M ̄ n =(0.8–1.5)×10 5 g/ mol, M ̄ w / M ̄ n ≤4.2 ). EO/glycidol copolymers and polyglycidol were obtained after cleavage of the acetal protecting group of the EEGE units. Polymers with hydrophilic backbone bearing hydrophobic stearyl moieties were obtained after modification of EO/glycidol copolymers with stearic acid. Their associating properties in aqueous solution were studied. Increasing either temperature or polymer concentration induces aggregate formation.

An NMR and Ionic Conductivity Study of Ion Dynamics in Liquid Poly(ethylene oxide)-Based Electrolytes Doped with LiN(SO2CF3)2

NMR and ionic conduction measurements have been performed for two liquid-state high-molecular-weight comb-branched polyethers, which are macromonomers of cross-linked random copolymers, with and without LiN(SO2CF3)2 (LiTFSI) doping. The macromonomers are derivatives of glycerol bonded to (ethylene oxide)-co-(propylene oxide) (m(EO−PO)) and (ethylene oxide)-co-(2-(2-methoxyethoxy)ethyl glycidyl ether) (m(EO−GE)) with molecular weights of about 8 000 and 10 000, respectively. The dynamics of the lithium ion, anion, and the macromonomers were characterized by 7Li, 19F, and 1H NMR spin−lattice relaxation time (T1) and self-diffusion coefficient (D) measurements. Because the temperature dependence of the 1H and 7Li NMR T1 exhibited minima, the reorientational correlation times were able to be calculated. Above 278 K, the segmental motions in the neat liquid-state macromonomers are faster than those in the cross-linked state, and they become almost the same at lower temperatures and are slowest in m(EO−PO). When doped with LiTFSI the segmental motions in the liquid electrolytes slowed to values similar to those in the cross-linked polymer. The translational diffusion coefficients were in the order (fastest to slowest) of anions > lithium ions > macromonomers. The diffusion of the ions correlated well with the macromonomer diffusion. The ionic conductivity of doped m(EO−PO) was higher than that of doped poly(EO−PO), and comparison of the measured ionic conductivity with estimates of the ionic conductivity calculated from Danion and DLi indicates high ion dissociation in the macromonomer electrolytes. The results are consistent with a picture of the lithium ions undergoing local motions near the polymer chains, whereas the anions diffuse through a slowly fluctuating three-dimensional porous polymer matrix.

Studies of the interface between lithium electrodes and polymeric electrolyte systems using in situ FTIR spectroscopy

This paper describes studies of the interface between lithium electrodes and solid electrolyte systems using in situ FTIR spectroscopy in a single internal reflectance mode. In this method, the masking effect of the electrolyte matrix components is largely avoided. We studied gel electrolytes based on polyvinylidene difluoride-hexafluoropropylene with cyclic alkyl carbonates as plasticizers, suitable for ambient temperatures, and a solvent free polymer, derivatives of polyethylene oxide (PEO) with a branched structure: poly[ethyleneoxide-2-(2-methoxyethoxy)ethyl glycidyl ether] at elevated temperatures. We found that the surface chemistry of Li electrodes in contact with the gel matrixes is dominated by alkyl carbonate solvent reduction to ROCO 2Li surface species. In the case of the PEO-based polymer, the surface reactions of Li electrodes are dominated by salt and trace water reduction. The polymer itself seems to be stable with lithium even at 60°C.

High ionic conductivity and electrode interface properties of polymer electrolytes based on high molecular weight branched polyether

Ionic conductivity and electrode interface properties of solid polymer electrolytes (SPE) based on high-molecular-weight branched polyethers have been studied for their application to solid state rechargeable lithium batteries. High molecular weight (105–106) comb-shaped polyethers, poly[ethylene oxide-co-2-(2-methoxyethoxy)ethyl glycidyl ether] [P(EO/MEEGE)], allow to give elastic and self-standing polymer electrolyte films without cross-linking. With increasing the MEEGE composition, the conductivity appreciably increases and takes a maximum at MEEGE compositions of 0.2–0.3, due to the fast ion transport assisted by highly mobile ether side-chains. Interfacial resistance (Ri) at the lithium electrode interface decreases with increasing ionic conductivities of the polymer electrolytes, which are affected by the MEEGE composition and lithium salt species complexed with the copolymers. An all-solid lithium polymer battery, Li/P(EO/MEEGE=91/9)-LiClO4/LiCoO2 composite cathode cell, exhibited a discharging life of over 7 h at 0.1 mA/cm2 and a low cell impedance of 96 Ω cm2 after full charge at 60°C.

Open spaces and molecular motions of polyether-based network polymers probed by positron annihilation

The lifetimes of positrons have been measured for network polymers based on polyethers. From the temperature dependence of the lifetime of ortho-positronium (o-Ps), τ3, for the network polymer of poly(ethylene oxide-co-propylene oxide) [P(EO/PO)], an onset temperature for limited local motions of molecules, Tγ, and the glass transition temperature, Tg, were determined to be 57 and 201 K, respectively. For the network polymer of poly[EO-co-2-(2-methoxyethoxy)ethyl glycidyl ether] [P(EO/MEEGE)], Tγ and Tg were determined to be 57 and 185 K, respectively. For both specimens, above 270 K, the observed linear temperature dependence of τ3 was attributed to the thermal expansion of open spaces in a liquid state. In the temperature range between Tγ and 270 K, for the P(EO/MEEGE) network, τ3 was longer and its intensity was smaller than those for the P(EO/PO) network. These results were attributed to the increase in the size of open spaces for the P(EO/MEEGE) network polymer and the blocking of these regions by motions of side chains and chain ends. © 1998 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 36: 1919–1925, 1998

Poly(α- t -butoxy-ω-styrylo-glycidol): a new reactive surfactant

Poly(α-t-butoxy-ω-styrylo-ethoxy ethyl glycidyl ether) was synthesized via the termination of the potassium t-butoxide initiated anionic polymerization of ethoxy ethyl glycidyl ether with p-chloromethylstyrene. The macromonomer was copolymerized with styrene. Subsequent hydrolysis of the copolymers leads to polystyrene - graft - polyglycidol. Poly(α-t-butoxy-ω-styrylo-glycidol), synthesized through the hydrolysis of the macromonomer so obtained, acts as reactive emulsifier (surfmer) in the emulsion copolymerization of styrene in water.

High ionic conductivity of new polymer electrolytes based on high molecular weight polyether comb polymers

High molecular weight polyether comb polymers, poly[ethylene oxide- co-2-(2-methoxyethoxy)ethyl glycidyl ether] P(EO/MEEGE), have been used as matrixes of polymer electrolytes. The high molecular weight (>10 6) polymers give self-standing and elastic polymer electrolyte films without chemically cross-linked structures at room temperature, when complexed with electrolyte salts. With increasing the composition of MEEGE in the copolymers, the degree of crystallinity of the polymer electrolytes decreases, and the ionic conductivity appreciably increases. The increase in the conductivity cannot be explained only by the crystallinity decrease, the increase in the number of highly mobile ether side chains with the increase in MEEGE composition contributes to achieving the high conductivity. The fast ion transport would be realized in cooperation with the fast side chain motion. The polymer electrolytes complexed with lithium bis(trifluoromethylsulfonyl)imide (LiTFSI) exhibit higher conductivity than those complexed with a conventional salt, lithium perchlorate. The polymer electrolytes, P(EO/MEEGE) containing 9 mol% of MEEGE complexed with LiTFSI, exhibit high ionic conductivities of 10 −4 S cm −1 at 30°C and 10 −3 Scm −1 at 80°C. An electrochemically stable potential window, established by solid state cyclic voltammetry using microelectrodes, is at least 4 V from the Li/Li + potential.

Molecular Relaxations of a Branched Poly(oxyethylene) Network Polymer

Dielectric relaxation measurements and 13C NMR measurements were carried out on an amorphous network polymer derived from poly[2-(2-methoxyethoxy)ethyl glycidyl ether]triol with 2,4-toluenediisocyanate. The main relaxation and the higher frequency relaxation were observed in the dielectric spectra. The main relaxation was found to be symmetrical and broad with a half width of 5 decades in a frequency domain. The higher frequency process is considered to be the γ process of ethylene oxide chains due to the local twisting mode. The temperature dependence of T1 and T1ρ of the ethylene oxide carbon showed minima and it is clearly shown that the relaxation times obtained from the dielectric measurements correspond to the relaxation time obtained from the T1ρ measurements of the ethylene oxide carbon. The temperature dependence of T1 was well described assuming the Cole-Cole spectral density function with the shape factor β obtained for the dielectric main relaxation. The 13C magnetization decay of the ethylene oxide carbon in the rotating frame was found to be given by two components (slow and fast components) below the relaxation temperature. The broad dielectric relaxation and the decay profiles of the ethylene oxide carbon are discussed in terms of the branched structure of the network.

Effects of network structures and incorporated salt species on electrochemical properties of polyether-based polymer electrolytes

Network polymer electrolytes were prepared by photo-crosslinking reactions of three different polyether triacrylate oligomers in the presence of lithium salts. 2-(2-Methoxyethoxy)ethyl glycidyl ether was used as a new monomer for the preparation of network polyethers having short ether side chains. Network polyethers having no side chains were also prepared for comparison. A new salt, lithium bis(trifluoromethanesulfonyl)imide, and a conventional salt, lithium perchlorate, were complexed with the network polyethers. The effects of the network structures and the incorporated salt species on the electrochemical properties, including ionic conductivity, Li + transport number, and electrochemical potential window, have been systematically studied.

Synthesis of polymer electrolytes based on poly[2‐(2‐methoxyethoxy)ethyl glycidyl ether] and their high ionic conductivity

AbstractNetwork polymer electrolytes based on poly[2‐(2‐methoxyethoxy)ethyl glycidyl ether] (PME2GE) were synthesized and characterized. The effects of crosslinking density, the introduction of ethylene oxide (EO) unit into the main chain by copolymerization, and the electrolyte (LiClO4) concentration on the ionic conductivity were explored. The random copolymer system improved the conductivity considerably compared with the polymer electrolytes previously obtained for network polymer systems and exhibited a high ionic conductivity of 10−4 S/cm at 40°C and 10−5 S/cm at 10°C, and even 3 X 10−7 S/cm at −20°C with optimization of the copolymer composition, the crosslinking density and the amount of LiClO4. The optimum composition was EO/ME2GE = 70/30 in molar ratio. The most preferable ratio of LiClO4 to etheric oxygen was in the range of 0.02–0.03.

Preparation and polymerization of spiroorthoester bearing the perfluoroalkyl group

AbstractFor a potential use of spiroorthoesters which polymerize with essentially zero shrinkage during polymerization, the preparation of spiroorthoester (I) bearing the perfluoroalkyl group was carried out. Spiroorthoester I was prepared by the reaction of ε‐caprolactone with 2‐(F‐octyl)ethyl glycidyl ether (II), obtained from 2‐(F‐octyl)ethanol and epichlorohydrin, in the presence of catalytic amount of BF3OEt2. Spiroorthoester I underwent the cationic ring‐opening polymerization by virtue of BF3OEt2 to obtain poly(ether‐ester) with 2.7% expansion on polymerization. The presence of the perfluoroalkyl group had no significant effect on the polymerization of the spiroorthoester.

Kinetics of the Polymerization of Ethyl Glycidil Ether and Allyl Glycidil Ether with BF3OEt2

Abstract The kinetics of the polymerization of ethyl glycidyl ether and allyl glycidyl ether with BF3OEt2 as catalyst has been studied. Chain transfer to the monomer has been evidenced. It increased with the monomer concentration and decreased with the increase of the dielectric constant of the solvent used and decreased in the presence of a monomer more basic than glycidyl ethers, for example, 1,3-dioxepane.