SUMMARY: Poly(1-vinylimidazole) (PVI) forms complexes with poly(styrenesulfonic acid) and the zinc salt of poly(styrenesulfonate) (PSSA and PSSZn, respectively) in water/ethanol (2 : 1 v/v) solution, indicating the presence of strong interactions. Infrared spectroscopic measurements showed the existence of protonated imidazole groups in all the complexes. X-ray photoelectron spectroscopic studies showed the development of high-binding-energy N(1) 1s and N(3) 1s peaks, but the values of the binding energy shift of N(3) 1s are larger than those of N(1) 1s in all PVI/PSSA and PVI/PSSZn complexes, suggesting proton transfer from PSSA to imidazole N(3) atoms in the PVI/PSSA complexes, and coordination between Zn 2+ and the imidazole N(3) atoms in the PVI/PSSZn complexes. Based on the values of the binding energy shift of the interacting nitrogen atoms, the strength of the coordination interaction in PVI/PSSZn complexes is weaker than the ionic interactions in the PVI/PSSA complexes. The development of a new S 2p spin-orbit split doublet at a low-binding-energy region reveals the existence of interactions between Zn 2+ and the imidazole nitrogen atoms.

Poly[lithium-N-(4-sulfophenyl)maleimide-co-methoxyoligo(oxyethylene)methacrylate], P(LiS-MOE n ), with three different oligo(oxyethylene) side chains (i.e., three different n values) have been synthesized. The copolymers are of a new type of comblike, nearly alternating copolymer electrolytes, showing single lithium ionic conductivity. All the three copolymers show a glass transition at about -50 °C (T g1 ). In addition, copolymers with n ) 7 and 12 also exhibit a second glass transition in the temperature range of 30-50 °C (T g2 ), while the copolymer with n ) 16 shows an endothermic peak near room temperature. T g1 is assigned to the oligo(oxyethylene) side chain, while T g2 is attributed to the main chain of the copolymer domain. The melting point (T m ) is attributed to the endothermic change of the partially crystalline phase formed by the long oligoether side chain. When the temperature is below 50 °C, P(LiSMOE n )s with larger n values have a higher ionic conductivity. When the temperature is above 50 °C, however, P(LiSMOE n )s with smaller n values show higher ionic conductivity because of their higher salt concentration. The maximum ionic conductivity at 30 °C is 1.5 × 10 -7 S cm -1 for n ) 16. The temperature dependence of ionic conductivity indicates that the Arrhenius behavior is not obeyed. The ionic conduction follows a special dual Vogel-Tamman-Fulcher (VTF) behavior.

A fullerene (C60)‐end‐capped poly(ethylene oxide) (FPEO) has been prepared by the cycloaddition reaction of monoazido‐terminated poly(ethylene oxide) with C60. The majority of the FPEO sample is the monoadduct as shown by thermogravimetry and X‐ray photoelectron spectroscopy. Most electronic characteristics of C60 are retained in the polymer as shown by its UV‐visible absorption spectrum. The incorporation of C60 reduces the extent of crystallinity of PEO by 17%. The miscibility behavior of FPEO with poly(p‐vinylphenol) (PVPh) was studied. Similar to PEO, FPEO is miscible with PVPh over the entire composition range. The hydrogen‐bonding interaction between FPEO and PVPh is as strong as that between PEO and PVPh as shown by Fourier‐transform infrared spectroscopy.

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Lithium ion conductive polymer electrolytes have attracted much attention because of their potential application in a variety of allsolid-state electrochemical devices, particularly high energy density, rechargeable lithium/lithium-ion batteries, sensors, and electrochromic display devices. [1][2][3] Solid polymer electrolytes serve two principal roles in rechargeable Li batteries. One is as the traditional electrolyte, i.e., the medium for ionic transport, and another is as the separator which insulates the cathode from the anode. Therefore, solid polymer electrolytes must exhibit high ionic conductivity in the order of 10 Ϫ3 S cm Ϫ1 at ambient temperatures, and a good mechanical strength preferably comparable to that of porous polyethylene and polypropylene separators such as the Celgard membranes used in conventional organic solvent-based lithium batteries. They should also possess a wide electrochemical stability window preferably between 0 and 4.5 V vs. Li ϩ /Li, and good compatibility with high voltage cathodes such as TiS 2 , V 6 O 13 , LiMn 2 O 4 , LiNiO 2 , and LiCoO 2 and low voltage anodes such as lithium and Li x C 6 . A high stability of the lithium/electrolyte interface, and a high lithium ion transference number preferably close to unity, are also desirable. Among the most promising examples of solid polymer electrolytes are hybrid (gel-type or plasticized-type) electrolytes obtained by the immobilization of solutions of lithium salts dissolved in organic solvents with high dielectric constants such as ethylene carbonate (EC), propylene carbonate (PC), dimethyl carbonate (DMC), and ␥-butyrolactone (BL), in polymer matrix such as polyacrylonitrile (PAN), poly(methyl methacrylate) (PMMA), poly(vinyl pyrrolidinone) (PVP), and poly(vinylidene fluoride) (PVdF). [4][5][6][7][8][9][10][11][12] Most of these hybrid electrolytes possess some of the properties required in lithium batteries.Recently, we have reported 13 the preparation of a novel microporous composite polymer electrolyte from microemulsion polymerization, based on the microemulsion system of acrylonitrile (AN), 4-vinylbenzenesulfonic acid lithium salt (VBSLi), ethylene glycol dimethacrylate (EGDMA, as cross-linker), -methoxy poly(ethyleneoxy) 40 undecyl-␣-methacrylate (C 1 -PEO-C 11 -MA-40, as surfactant), and water. The microemulsion-polymerized membranes were extracted with ethanol, thoroughly dried in a vacuum oven at 100ЊC, and could be saturated with organic plasticizers or electrolyte solutions. The membranes saturated with EC-DMC, BL, and PC-EC had an ionic conductivity of ca. 7 ϫ 10 Ϫ5 S cm Ϫ1 , while the membranes saturated with 1 M LiClO 4 /EC-DMC (1:1 by vol-ume) or 1 M LiBF 4 /BL showed room temperature conductivities close to 10 Ϫ3 S cm Ϫ1 . Such polymer electrolytes, formed by incorporating the solutions of lithium salts in plasticizers into the microporous polymer membranes, may be called the composite polymer electrolytes (abbreviated as (CPEs).In this paper, we present a detailed investigation into the ionic conductivity and ...