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1.
A work was carried out on a solid polymeric electrolyte system comprising blends of poly (vinyl chloride) and liquid 50% epoxidized natural rubber (LENR50) as a polymer host with LiClO4 as a salt and prepared by solution casting technique. In this paper, the main study was the effect of LiClO4 salt concentration on the electrolyte properties. The effect of the salt on the electrolyte properties was characterized and analyzed with impedance spectroscopy (EIS), X‐ray diffraction (XRD), differential scanning calorimeter (DSC), and scanning electron microscopy (SEM). The EIS result showed that highest ionic conductivity was obtained at 30 wt % salt with a value of 2.3 × 10?8 S cm?1. The XRD results revealed that the LiClO4 salt was fully complexed within the polymer host as no sharp peaks were observed. However, above 30 wt % of salt, some sharp peaks were observed. This phenomenon was caused by the association of ions. Meanwhile, DSC analysis showed that Tg increased as the salt content increased. This implied that LiClO4 salt had interaction with polymer host by forming coordination bond. The morphologies' studies showed that good homogeneity and compatibility of the electrolyte were achieved. Upon the addition of the salt, formation of micropores occurred. It was noted that micropores which aid in mobility of ions in the electrolyte system has increased the ionic conductivity. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

2.
Low crosslinked copolymer of linear and hyperbranched polyurethane (CHPU) was prepared, and the ionic conductivities and thermal properties of the composite polymer electrolytes composed of CHPU and LiClO4 were investigated. The FTIR and Raman spectra analysis indicated that the polyurethane copolymer could dissolve more lithium salt than the corresponding polymer electrolytes of the non crosslinked hyperbranched polyurethane, and showed higher conductivities. At salt concentration EO/Li = 4, the electrolyte CHPU30‐LiClO4 reached its maximum conductivity, 1.51 × 10?5 S cm?1 at 25°C. DSC measurement was also used for the analysis of the thermal properties of polymer electrolytes. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 3607–3613, 2007  相似文献   

3.
Poly(PEG200 maleate) was synthesized as a new type crosslinkable prepolymer and the semi‐interpenetrating polymer network (semi‐IPN) gel electrolytes were prepared by means of thermal polymerization. Their intrinsic properties were characterized by FTIR spectroscopy, differential scanning calorimetry (DSC), X‐ray diffractions (XRD), scanning electron microscopy, alternating current impedance (AC impedance), and linear sweep voltammetry. The prepared polymer hosts are transparent and have good mechanical properties. The results of DSC and XRD confirm that the prepared hosts are in amorphous state and they can hold enough liquid electrolytes, which is favorable for Li+ ions to transport via both the absorbed liquid electrolyte and the gel of the entire systems. The semi‐IPN gel electrolytes exhibit high ionic conductivity on the order of 10?3 S cm?1. Their electrochemical stability up to +4.6 V against Li+/Li also makes them potential candidates for application as polymer electrolytes in devices. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008  相似文献   

4.
Flexible, transparent, and crosslinked polymer films were synthesized by polymerization of PEG‐modified urethane acrylate using a simple method. A series of novel solid polymer electrolytes and gel electrolytes were prepared based on this type of polymer film. To understand the interactions among salt, solvent, and polymer, the swelling behaviors of the crosslinked polymer in pure propylene carbonate (PC) and liquid electrolyte solutions (LiClO4/PC) were investigated. The results showed that the swelling rate in the electrolyte solution containing moderate LiClO4 was greater than that in pure PC. Thermogravimetric analysis (TGA) also supported the interaction between the solvent and polymer. The morphology and crystallinity of the crosslinked polymer and polymer electrolytes were studied using atomic force microscopy (AFM) and wide‐angle X‐ray diffraction (WAXD) spectroscopy. The effects of the content of the electrolyte solution on the ionic conductivity of gel electrolytes were explored. The dependence of the conductivity on the amount of the electrolyte solution was nonlinear. With a different content of the plasticizer, the ionic conduction pathway of the polymer electrolytes would be changed. The best ionic conductivity of the gel electrolytes, which should have good mechanical properties, was 4 × 10r?3 S cm?1 at 25°C. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 340–348, 2003  相似文献   

5.
The study presents preparation of poly methyl methacrylate (PMMA) based nanocomposite gel polymer electrolytes consisting of, salt lithium perchlorate (LiClO4), plasticizer PC/DEC and different proportions of SiO2 nanofiber by solution casting process. The effect of the composition of the electrolytes on their ionic, mechanical and thermal characteristics was investigated. Morphology of the nanocomposite electrolyte films has been observed by scanning and transmission electron microscopes. Interactions among the constituents of the composite and structural changes of the base polymer were investigated by Fourier Transform Infrared (FTIR) spectroscopy and X-ray diffraction (XRD) techniques. The maximum conductivity i.e. 10?3 Scm?1 at room temperature is obtained with the electrolyte composition of 0.6(PMMA)-0.15(PC + DEC)-0.1LiClO4 (wt%) containing 10 wt% SiO2 nanofiber and the temperature dependent conductivity data of the electrolyte follows Vogel-Tamman-Fulcher (VTF) behavior.  相似文献   

6.
The proton conducting polymer blend electrolytes based on poly(vinyledine fluoride):poly(vinyl alcohol) (PVdF:PVA) polymer blend, doped with ammonium acetate (CH3COONH4) in different concentrations, have been prepared by a solution casting technique using dimethyl formamide (DMF) as solvent. The increase in amorphous nature of the polymer electrolytes has been confirmed by X-ray diffraction analysis (XRD). The Fourier transform infrared spectroscopy (FTIR) analysis confirms the complex formation between the polymers and the salt. From the ac impedance spectroscopic analysis, the ionic conductivity of 5 MWt% CH3COONH4-doped PVdF:PVA polymer blend electrolyte has been found to be maximum of 1.30 × 10?6 S/cm at room temperature.  相似文献   

7.
Potassium ion-conducting polymer electrolytes based on poly (vinyl pyrrolidone) (PVP) complexed with KClO4 were prepared using a solution cast technique. These samples were characterized using X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Differential Scanning Calorimetry (DSC), and impedance spectroscopy. The complexation of the salt with polymer was confirmed by FT-IR and XRD studies. The ionic conductivity was found to increase with increasing temperature and salt concentration. The highest ionic conductivity (0.91 × 10?5 S/cm) and low activation energy (0.29 eV) was obtained for the polymer complexed with 15 wt% KClO4 among all the compositions.  相似文献   

8.
A new hybrid polymer electrolyte system based on chemical‐covalent polyether and siloxane phases is designed and prepared via the sol–gel approach and epoxide crosslinking. FT‐IR, 13C solid‐state NMR, and thermal analysis (differential scanning calorimetry (DSC) and TGA) are used to characterize the structure of these hybrids. These hybrid films are immersed into the liquid electrolyte (1M LiClO4/propylene carbonate) to form plasticized polymer electrolytes. The effects of hybrid composition, liquid electrolyte content, and temperature on the ionic conductivity of hybrid electrolytes are investigated and discussed. DSC traces demonstrate the presence of two second‐order transitions for all the samples and show a significant change in the thermal events with the amount of absorbed LiClO4/PC content. TGA results indicate these hybrid networks with excellent thermal stability. The EDS‐0.5 sample with a 75 wt % liquid electrolyte exhibits the ionic conductivity of 5.3 × 10?3 S cm?1 at 95°C and 1.4 × 10?3 S cm?1 at 15°C, in which the film shows homogenous and good mechanical strength as well as good chemical stability. In the plot of ionic conductivity and composition for these hybrids containing 45 wt % liquid electrolyte, the conductivity shows a maximum value corresponding to the sample with the weight ratio of GPTMS/PEGDE of 0.1. These obtained results are correlated and used to interpret the ion conduction behavior within the hybrid networks. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1000–1007, 2006  相似文献   

9.
Polymer electrolyte membranes composing of corn starch as host polymer, lithium perchlorate (LiClO4) as salt, and barium titanate (BaTiO3) as composite filler are prepared using solution casting technique. Ionic conductivity is enhanced on addition of BaTiO3 by reducing the crystallinity and increasing the amorphous phase content of the polymer electrolyte. The highest ionic conductivity of 1.28 × 10?2 S cm?1 is obtained for 10 wt % BaTiO3 filler in corn starch‐LiClO4 polymer electrolytes at 75°C. Glass transition temperature (Tg) of polymer electrolytes decreases as the amount of BaTiO3 filler is increased, as observed in differential scanning calorimetry analysis. Scanning electron microscopy and thermogravimetric analysis are employed to characterize surface morphological and thermal properties of BaTiO3‐based composite polymer electrolytes. The electrochemical properties of the electric double‐layer capacitor fabricating using the highest ionic conductivity polymer electrolytes is investigated using cyclic voltammetry and charge‐discharge analysis. The discharge capacitance obtained is 16.22 F g?1. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43275.  相似文献   

10.
We report the synthesis of all‐solid‐state polymeric electrolytes based on electrospun nanofibers. These nanofibers are composed of polyethylene oxide (PEO) as the matrix, lithium perchlorate (LiClO4) as the lithium salt and propylene carbonate (PC) as the plasticizer. The effects of the PEO, LiClO4 and PC ratios on the morphological, mechanical and electrochemical characteristics were investigated using the response surface method (RSM) and analysis of variance test. The prepared nanofibrous electrolytes were characterized using SEM, Fourier transform infrared, XRD and DSC analyses. Conductivity measurements and tensile tests were conducted on the prepared electrolytes. The results show that the average diameter of the nanofibers decreased on reduction of the PEO concentration and addition of PC and LiClO4. Fourier transport infrared analysis confirmed the complexation between PEO and the additives. The highest conductivity was 0.05 mS cm?1 at room temperature for the nanofibrous electrolyte with the lowest PEO concentration and the highest ratio of LiClO4. The optimum nanofibrous electrolyte showed stable cycling over 30 cycles. The conductivity of a polymer film electrolyte was 29 times lower than that of the prepared nanofibrous electrolyte with similar chemical composition. Furthermore, significant fading in mechanical properties was observed on addition of the PC plasticizer. The results obtained imply that further optimization might lead to practical uses of nanofibrous electrolytes in lithium ion batteries. © 2019 Society of Chemical Industry  相似文献   

11.
The interaction behavior of solid‐state polymer electrolytes composed of poly(ethylene oxide) (PEO)/novolac‐type phenolic resin and lithium perchlorate (LiClO4) was investigated in detail by DSC, FTIR, ac impedance, DEA, solid‐state NMR, and TGA. The hydrogen bonding between the hydroxyl group of phenolic and ether oxygen of the PEO results in higher basicity of the PEO. The higher basicity of the ether group can dissolve the lithium salts more easily and results in a greater fraction of “free” anions and thus higher ionic conductivity. DEA results demonstrated that addition of the phenolic increases the dielectric constant because of the partially negative charge on the ether group induced by the hydrogen bonding interaction between ether oxygen and the hydroxyl group. The study showed that the blend of PEO(100)/LiClO4(25)/phenolic(15) possesses the highest ionic conductivity (1.5 × 10?5 S cm?1) with dimensional stability. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1207–1216, 2004  相似文献   

12.
The polymer electrolytes comprising of PVdF-HFP/PVAc/Mg(ClO4)2 as salt based polymer blend electrolytes derived from the addition of varying amounts of 1-ethyl – 3-methylimidazolium trifluoromethane sulfonate [EMITF], as dopant were synthesized in the form of films by solution-casting method. The XRD and FTIR patterns confirm the formation of an amorphous phase and also that complex formation between the polymers, salt and ionic liquid. The SEM images show that the polymer electrolyte exhibit a enormous pores, remarkably, the maximum ionic conductivity is obtained in the case of the typical polymer system I3 is found to be 9.122 × 10?4 Scm?1at 303 K.  相似文献   

13.
The transparent and flexible solid polymer electrolytes (SPEs) were fabricated from polyacrylonitrile‐polyethylene oxide (PAN‐PEO) copolymer which was synthesized by methacrylate‐headed PEO macromonomer and acrylonitrile. The formation of copolymer is confirmed by Fourier‐transform infrared spectroscopy (FTIR) measurements. The ionic conductivity was measured by alternating current (AC) impedance spectroscopy. Ionic conductivity of PAN‐PEO‐LiClO4 complexes was investigated with various salt concentration, temperatures and molecular weight of PEO (Mn). And the maximum ionic conductivity at room temperature was measured to be 3.54 × 10?4 S/cm with an [Li+]/[EO] mole ratio of about 0.1. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 461–464, 2006  相似文献   

14.
2,4‐Toluene diisocyanate, poly(propylene glycol), poly(ethylene glycol) (PEG) and 2‐hydroxyethyl methacrylate were used to synthesize PEG–UA (urethane acrylate) monomer. The crosslinked polymer and gel polymer electrolytes were prepared in dioxane by free radical polymerization. The swelling behaviour, thermal degradation properties, morphology and ionic conductivity of the gel polymer electrolytes were investigated. With decrease in the proportion of dioxane used, the synthesized polymer's network density increased, its affinity with a solution of 1 M LiClO4 in propylene carbonate (PC) decreased, and more microgel which diffused in the network. At the same time, the conductivity increased and reached 4 × 10?4 S cm?1 at 25 °C. Copyright © 2003 Society of Chemical Industry  相似文献   

15.
In this work, polymer electrolytes composed of PAN/PMMA/LiClO4 with different plasticizers are prepared using solvent casting technique. Ionic conductivity of the electrolytes is evaluated with the help of ac impedance study at various temperatures. Structural and the complexation of the prepared electrolytes are studied by XRD and FTIR analysis, respectively. Thermogravimetric/differential thermal analysis (TG/DTA) is used to find the thermal stability of the polymer electrolytes. PAN/PMMA/EC/LiClO4-based plasticized polymer electrolyte is found to possess optimal properties in terms of conductivity and thermal stability. Porous nature of the polymer gel electrolytes is also confirmed by SEM analysis.  相似文献   

16.
A series of solid polymer electrolytes (SPEs) based on comb‐like nonionic waterborne polyurethane (NWPU) and LiClO4 are fabricated via a solvent free process. The NWPU‐based SPEs have sufficient mechanical strength which is beneficial to their dimensional stability. Differential scanning calorimetry analysis indicates that the phase separation occurs by the addition of the lithium salt. Scanning electron microscopy and X‐ray diffraction analyses illustrate the good compatibility between LiClO4 and NWPU. Fourier transform infrared study reveals the complicated interactions among lithium ions with the amide, carbonyl and ether groups in such SPEs. AC impedance spectroscopy shows the conductivity of the SPEs exhibiting a linear Arrhenius relationship with temperature. The ionic conductivity of the SPE with the mass content of 15% LiClO4 (SPE15) can reach 5.44 × 10?6 S cm?1 at 40 °C and 2.35 ×10?3 S cm?1 at 140 °C. The SPE15 possesses a wide electrochemical stability window of 0–5 V (vs. Li+/Li) and thermal stability at 140 °C. The excellent properties of this new NWPU‐based SPE are a promising solid electrolyte candidate for all‐solid‐state lithium ion batteries. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45554.  相似文献   

17.
A comb‐like polyether, poly(3‐2‐[2‐(2‐methoxyethoxy)ethoxy]ethoxymethyl‐3′‐methyloxetane) (PMEOX), was reacted with hexamethylene diisocyanate and extended with butanediol in a one‐pot procedure to give novel thermoplastic elastomeric poly(ether urethane)s (TPEUs). The corresponding hybrid solid polymer electrolytes were fabricated through doping a mixture of TPEU and poly(vinylidene fluoride) with three kinds of lithium salts, LiClO4, LiBF4 and lithium trifluoromethanesulfonimide (LiTFSI), and were characterized using differential scanning calorimetry, thermogravimetric analysis and Fourier transform infrared spectroscopy. The ionic conductivity of the resulting polymer electrolytes was then assessed by means of AC impedance measurements, which reached 2.1 × 10?4 S cm?1 at 30 °C and 1.7 × 10?3 S cm?1 at 80 °C when LiTFSI was added at a ratio of O:Li = 20. These values can be further increased to 3.5 × 10?4 S cm?1 at 30 °C and 2.2 × 10?3 S cm?1 at 80 °C by introducing nanosized SiO2 particles into the polymer electrolytes. Copyright © 2006 Society of Chemical Industry  相似文献   

18.
A blend of poly(methyl methacrylate) (PMMA) and poly(styrene‐co‐acrylonitrile) (PSAN) has been evaluated as a composite polymer electrolyte by means of differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy, ac impedance measurements, and linear sweep voltammetry (LSV). The blends show an interaction with the Li+ ions when complexed with lithium perchlorate (LiClO4), which results in an increase in the glass‐transition temperature (Tg) of the blends. The purpose of using PSAN as another component of the blend is to improve the poor mechanical properties of PMMA‐based plasticized electrolytes. The mechanical property is further improved by introducing fumed silica as inert filler, and hence the liquid electrolyte uptake and ionic conductivity of the composite systems are increased. Room‐temperature conductivity of the order of 10?4 S/cm has been achieved for one of the composite electrolytes made from a 1/1 blend of PSAN and PMMA containing 120% liquid electrolyte [1M LiClO4/propylene carbonate (PC)] and 10% fumed silica. These systems also showed good compatibility with Li electrodes and sufficient electrochemical stability for safe operation in Li batteries. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1319–1328, 2001  相似文献   

19.
A series of polyurethanes (PUs) with different polyether soft segments [polydioxolane (PDXL), polyethylene glycol (PEG), or PDXL/PEG] were synthesized successfully, and solid polymer electrolytes based on PU/LiClO4 complexes were prepared. The relations between structure and the ionic conductive properties of the PU‐based electrolytes were investigated by means of Fourier transform infrared spectroscopy, differential scanning calorimetry, dynamic mechanical analysis, and complex impedance analysis. Results showed that the glass‐transition temperature (Tg) of PDXL–PU was lower than that of PEG–PU. Doped lithium perchlorate (LiClO4) salt could be dissolved well in soft segments of PDXL–PU. The ionic conductivity of the PDXL–PU/LiClO4 complex could reach a value of 2 × 10?5 S/cm at room temperature without the addition of an organic plasticizer. The system with PDXL/PEG as a soft segment had a higher Tg and a lower ionic conductivity than the one with PDXL as a soft segment. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 103–111, 2002  相似文献   

20.
Poly(vinyl chloride) (PVC)—poly(butyl methacrylate) (PBMA) blended polymer electrolytes with lithium perchlorate (LiClO4) as the complexing salts are prepared by solution casting technique. The addition of PBMA into PVC matrix is found to induce considerable changes in physical and electrical properties of the polymer electrolytes. Addition of PBMA into PVC matrix is found to increase the conductivity by two orders of magnitude (1.108 × 10?5 S cm?1) when compared with that of the pristine PVC polymer electrolyte (10?7 S cm?1). Structural, thermal, mechanical, morphological, and polymer–salt interactions are ascertained from X‐ray diffraction (XRD), thermogravimetry/differential thermal analysis (TG/DTA), mechanical analysis, scanning electron microscope (SEM), and Fourier transform infrared spectroscopy (FTIR) respectively. A thermal stability upto 250 °C is asserted from the TG/DTA analysis. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44939.  相似文献   

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