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11.
PEO-LiClO4-Li1.3Al0.3Ti1.7 (PO4)3复合聚合物电解质电导率   总被引:1,自引:0,他引:1       下载免费PDF全文
将实验室烧制的无机快离子导体盐Li1.3Al0.3Ti1.7 (PO4)3PEO 与LiClO4 按照EO/ Li = 8, 两种锂盐含量为变量进行复合, 通过溶液浇注法制备得到PEO-LiClO4-Li1.3Al0.3Ti1.7 (PO4)3 复合聚合物电解质膜, 以示差扫描热分析法(DSC) 与电化学阻抗( EIS) 测试其性能。DSC 测试结果表明: 按照EO/ Li = 8 将Li1.3Al0.3Ti1.7 (PO4)3 、LiClO4PEO 复合的聚合物电解质中PEO 的结晶度由50.34 %下降到4.36 %~28.53 %。室温下该聚合物电解质所有试样的阻抗谱图在高频区呈现为压缩的半圆, 在低频区为一条倾斜的直线, 而在较高温度时, 阻抗谱图主要为一条倾斜的直线。复合聚合物电解质PEO-LiClO4-Li1.3Al0.3Ti1.7 (PO4)3 的离子电导率遵从Arrhe2nius 关系, 在Li1.3Al0.3Ti1.7 (PO4)3 质量分数达到15 %时, 活化能最低, 即4.494425 eV, 此时电导率值最佳, 373 K时为1.161 ×10 -3 S/ cm 和298 K时为7.985 ×10-6 S/ cm。  相似文献   
12.
采用溶液浇注法制备了PEO基聚合物电解质,测定了该类电解质的电导率,并研究了温度、SiO2的颗粒度及表面性能对聚环氧乙烯/高氯酸锂(PEO/LiClO4)聚合物电解质体系电导率的影响.结果表明PEO-LiClO4-10%SiO2复合型聚合物电解质的室温电导率达到了1.033×10-4S/cm,同时对该电解质进行了差热分析,发现加入SiO2后,PEO/LiClO4体系熔融温度降低,非晶相含量增加,有利于提高离子电导率.  相似文献   
13.
1 IntroductionItiswell establishedthatsomeinorganiclayeredcompoundssuchasMoO3 ,V2 O5canbeintercalatedbyavarietyofalkaliions (Li+ ,Na+ ,etc .) ,atomsandlargermoleculestoformintercalationhost guestcompounds ,whichareexpectedtobeusedaspotentialcathodicmate rialsinsecondaryLibatteriesandelectrochromicdevice s[1] .Thepolymer layeredoxidenanocompositeshaveat tractedmuchattentionduetotheirspecialstructureaswellassuperiorelectrical,electrochemicalandopticalproperties .Recently ,nanocompositesof (P…  相似文献   
14.
Poly ethylene oxide (PEO)x−V2O5−V2O5−MoO3 (x=0, 0.5, 1) films were prepared by the sol-gel method. The synthesis and structure of the films were investigated by XRD, TG-DTA, FTIR, etc. The results show that V2O5−MoO3 xerogel has a layered structure and its interlayer space increased from 1.3181 nm at x=0 to 1. 7898 nm at x=1 after the nanocomposite films were dried, and PEO in the interlayer changes the interface structure by forming hydrogen bonds with V=0 bands. CV measurement indicates that the intercalation of PEO improves insertion/extration properties of Li+ ions in the interlayer. ZHENG Jin-xia: Born in 1976 Funded by the National Natural Science Foundation of China (No. 50172036) and Natural Science Foundation of Hubei Province(No. 2001ABB083)  相似文献   
15.
采用静电纺丝法制备了聚苯胺/聚环氧乙烷( PANI/PEO)纳米纤维,研究了电压、接收距离对电纺PANI/PEO纳米纤维直径的影响,对电纺参数进行了优化。通过对电纺接收端的控制,制备了平行纳米纤维阵列,实现了纳米纤维的定向排布;通过对电纺射流沉积次数的控制,制备了PANI/PEO纳米单纤维传感器,并对NH3进行了气敏性测试。结果表明:当电纺电压为20 kV且接收距离为20 cm时,获得的PA-NI/PEO纳米纤维直径为105 nm,且形貌较佳,在此优化参数条件下制备的单纤维PANI/PEO纳米传感器在常温下对低浓度的NH3有良好的线性响应输出。  相似文献   
16.
PEO/PVA水凝胶伤口敷料的毒性和疗效评价   总被引:4,自引:0,他引:4  
为了证价经冻融循环处理和电子束辐射交联接技术术合成的聚氧化乙烯与聚乙烯醇(PEO/PVA)混合物水凝胶伤口敷料的性能,研究了该水凝胶膜对机体和细胞的毒性以及对皮肤伤口的愈合作用。毒性作用通过仇性全身毒性试验、细胞毒性试验和皮肤斑贴试验检测。细胞毒性试验应用高敏感性的成纤维细胞持续培养7d的RPMI-16402培养系统,检测细胞生长抑制和镜下细胞形态学变化。结果显示,PEO/PVA水凝胶敷料没有引起  相似文献   
17.
聚氧化乙烯-蒙脱土复合聚合物电解质室温电导率的研究   总被引:1,自引:0,他引:1  
李冰  王继库  林海云 《辽宁化工》2006,35(7):379-381,403
采用溶液浇铸法对蒙脱土与聚氧乙烯、LiClO4进行复合制备了聚合物电解质膜。用X射线衍射对蒙脱土及电解质膜进行了结构表征。采用交流阻抗法对复合型电解质膜的离子电导率进行了测试。结果表明:一定量的蒙脱土可以使(PEO)16LiClO4的离子电导率提高几倍。蒙脱土对基体离子电导率提高程度的不同取决于蒙脱土的含量。  相似文献   
18.
Nanocomposite polymer electrolytes (NCPEs) were prepared by blending poly (vinylidene fluoride-co-hexafluoro propylene) copolymer (PVdF-HFP) and polyethylene oxide (PEO) polymers and incorporation of ZnO inorganic nanofiller (PVdF-HFP:PEO:EC:PC:NaI:I2:ZnO). The highest ionic conductivity value of 8.36 mS cm−1 was recorded when 3 wt.% of ZnO inorganic nanofiller was incorporated into the NCPE system. Temperature-dependant ionic conductivity behaviour of NCPEs was analysed and proven to follow the Arrhenius thermal activated model. Structural studies of NCPEs were carried out using X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy analysis. NCPEs were used to fabricate Dye-sensitized solar cells (DSSCs). Enhancements in the solar light to electricity conversion efficiency (η) of DSSCs were observed in the presence of ZnO inorganic nanofiller in the NCPE system and NCPE with 3 wt.% ZnO represented the highest η of 7.33% under full sun irradiation.  相似文献   
19.
The polymer electrolyte based poly(ethylene oxide) complexed with conducting polyaniline (PANI) has been prepared in different weight percentages. The complexation is confirmed by Fourier transform infrared spectroscopy (FTIR).The change in morphology is studied by using scanning electron microscopy. The DC conductivity measurements are carried out using Keithley digital multimeter. It is seen that DC conductivity shows exponential behavior for all PEO : PANI complexes. It is observed that among all the PEO : PANI complexes, 50 wt % of PEO in PANI shows highest conductivity. Electrochemical cell parameters for battery applications at room temperature also have been determined. The samples are fabricated for battery application in the configuration of Na:(PEO : PANI):(I2 + C + sample), and their experimental data are measured using Wagner polarization technique. The cell parameters results in an open-circuit voltage of 0.4 V and a short-circuit current of 902 μA for PEO : PANI (50 : 50) composite. Hence, these composites can be better candidates for the polymer electrolyte studies. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   
20.
Di-block copolymers of poly(ethylene oxide) (PEO) and glycopolymers at three different pendant spacer lengths of glucose moiety were synthesized by deacetylation of pendant moieties of 2,3,4,6-tetra-O-acetyl-d-glucopyranosides which were prepared by reversible addition-fragmentation chain-transfer (RAFT) process. The water soluble deacetylated copolymers, PEO-b-poly(acryl-d-glucopyranoside) (PEO-b-PAG, 2a), PEO-b-poly[4′-(acryloxy)butyl-d-glucopyranoside] (PEO-b-PABG, 2b), and PEO-b-poly[6′-(acryloxy)hexyl-d-glucopyranoside] (PEO-b-PAHG, 2c) were characterized in comparison with acetylated copolymers by spectroscopic and gel permeation chromatography methods. In order to assess the biocompatibility of these three di-block copolymers, the adhesion (%), viability (%), and proliferation assays were carried out in MC3T3 cells in-vitro at different concentrations from 10 nM to 1000 μM. Qualitative analysis of cell cytoskeletal organization was obtained by immunostaining with talin and integrin α5. It was clearly indicative of well spreading of cells in the presence of all glycopolymers at lower concentrations but with an increase in the concentration (10 and 100 μM) showed significant change in the cell surface morphologies, despite having good cell adhesion and viability as compared to the control conditions. The use of di-block glycolpolymers at?≤?100 μM of the concentration showed very good osteoblast cells adhesion and viability response; however at higher concentrations (1000 μM) of glycopolymers > 80% of cells lost their viability.  相似文献   
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