聚合物单阳离子导体的制备—羧酸型梳状单离子导体

本文报道一种制备聚合物单阳离子导体的新方法。马来酸酐－醋酸乙烯酯及马来酸酐－苯乙烯共聚物以聚乙二醇单甲醚醇解，使酸酐环打开而得到带有聚乙二醇侧链的羧酸型梳状聚合物，其锂盐在加入适当增塑剂成膜后，可作为聚合物单阳离子导体，其结构以非晶态为主，具有较低的玻璃化转变温度及较好的热稳定性，增塑后的室温电导率最高可达１０＾－６Ｓ／ｃｍ。此外还研究了聚合物结构、阳离子半径、增塑剂、温度及外加额率等因素对电导率     

含聚氧化乙烯侧链的聚合物凝胶电解质的动态力学性能和离子导电性

红外测试结果表明：产物是含聚氧化乙烯侧链的聚合物。该聚合物电解质的室温电导率为10^-3S／cm数量级。并用动态力学方法,研究了分子链段活动性与聚合物凝胶电解质组成(增塑剂含量、含盐量和盐种类)的关系。     

聚合物电解质中增塑剂的研究进展

聚合物电解质在锂离子电池中有很好的应用前景,已成为当前锂离子电池研究领域的热点之一.但由于其室温电导率低,在实际应用中受到诸多限制.通常采用在聚合物电解质中添加适当比例的增塑剂以提高其离子电导率的方法来弥补此缺陷.本文综述了聚合物电解质中增塑剂的增塑原理、增塑剂的种类以及电解质中新型增埋剂的研究状况.     

新型梳状聚合物电解质的离子导电性 Ⅱ.侧链是分子量为550的聚乙二醇单甲醚

以乙烯／马来酸酐共聚物为骨架，聚乙二醇单甲醚（Ｍ＝５５０）为侧链，通过两步酯化，合成了梳状乙烯／马来酸酐共聚物多缩乙二醇酯，用ＩＲ、元素分析、交流复阻抗谱等对产物及其ＬｉＣｌＯ４盐复合物进行了研究。结果表明：所合成的产物为非晶的梳状聚合物，并严格按反应方程式生成半酯。盐浓度与电导率的关系在所研究的浓度范围内存在两个峰，一峰在Ｏ／Ｌｉ＋＝８；另一峰在Ｏ／Ｌｉ＋＝３０。用侧链ＰＥＯ玻璃化转变温度作Ｔ０，以ｌｏｇσ对１／Ｔ－Ｔ０作图，电导率与温度关系呈典型的ＶＴＦ行为，该体系室温电导率最高可达２．５８×１０－５Ｓ／ｃｍ。     

聚醚介质中的离子传导机理

以单阳离子导体作为传导模型,通过对阳离子淌度的表征,证实了碱金属盐在聚合物介质中的负温度依赖性。发现在离子传导过程中,离子淌度对其电导率温度依赖性的影响远甚于载流离子数。并运用聚合物链段松驰理论对这种反常离解行为进行了唯象学的诠释。     

羧酸型聚乙二醇聚氨酯离聚物及其导电性能

以聚环氧乙烷（ＰＥＯ）为软段，与４，４’－二苯甲烷二异氰酸酯（ＭＤＩ）预聚，以２，２’－二羟甲基丙酸（ＤＭＰＡ）扩链合成了含羧酸基团的聚氨酯，并经中和形成了含不同金属离子的离聚物．测定了样品的热分析数据和力学性能，利用交流阻抗分析仪测定了样品的阻抗谱，由此计算出样品的离子电导率．这类样品由于阴离子（－ＣＯＯ－）固定在聚合物分子链上，因此只有单一阳离子迁移．结果表明，羧酸型聚氨酯离聚物既有较高的单一离子电导率又具有优良的力学性能．讨论了不同软段分子量、硬段含量和金属抗衡离子对离子电导性能的影响     

梳形聚醚全固态聚合物电解质的电导率研究

应用阳离子开环聚合反应合成含二缩三乙二醇单甲醚侧链的梳形聚醚POE,并与高氯酸锂复配制成聚合物电解质.交流阻抗测试表明,当POE电解质内的氧锂比(O/L i)为20时,其电导率最高,室温下为10-4.43S/cm,80℃时则达到10-3.44S/cm.用DSC和XPS分别表征了链段运动能力和锂盐在POE中的溶解状态对电导率的影响.     

掺杂和取代对聚苯胺导电性能影响机制的研究

在导电聚合物的研究中，聚苯胺及其衍生物一直是人们相当感兴趣的课题．此类聚合物既可用氧化剂掺杂，也可进行质子酸掺杂，掺杂后其电导率可提高约十个数量级｛1，’］；利用在主链上引入取代基等化学修饰方法，可方便地调节其溶解性、加工性等物理化学性能．已有的研究结果表明，主链的化学修饰往往给聚苯胺的导电性能带来不利影响＊．因此，如何使聚苯胶类导电聚合物保持高的电导率且同时具备优良的物理加工性能使成为此类导电聚合物研究中的一个亟待解决的问题一本文利用鼻子化学EHMO－CO方法对掺杂和取代影响聚苯胺及其衍生物导电性…     

可溶性共轭聚席夫碱的合成、表征及电性能

本文以对苯二胺分别与乙二醛、丁二酮、３，４－己二酮和４，５－辛二酮缩聚合成了四种主链结构相同而侧基各异的新颖共轭性聚席夫碱．采用红外光谱和元素分析等方法对聚合物进行了表征．发现带有侧烷基的共轭性聚席夫碱能溶于一般有机溶剂；不同侧基的聚席夫碱溶解性是：两基聚席夫碱＞乙基聚席夫碱＞甲基聚度夫碱．测定了四种共轭聚席夫碱的本征导电率及其与温度的关系，结果表明，聚合物具有半导体性质．当聚合物以碘掺杂后，导电率可从１０－１１－１０－１２Ｓ／ｃｍ增加到１０－３－１０－４Ｓ／ｃｍ．探讨了共轭聚合物的侧基取代对掺杂后导电性的影响．     

聚N－（4，4＇－联吡啶盐）－p－乙烯基吡啶的电还原及光还原行为

合成了三种新型的主链为聚４－乙烯基吡啶的侧链型紫精聚合物和相应的小分子紫精，研究了它们的电还原及光还原行为。结果表明这类侧链型紫精聚合物的电还原和在异丙醇水溶液中的光还原都存在明显的聚合物效应，还原后生成的自由基正离子分子内缔合的倾向比相应的小分子紫精大得多．     

梳状高分子固体电解质的离子导电性研究

深入研究了交替马来酸酐共聚物多缩乙二醇酯（ＣＰ３５０）两种锂盐络合物ＣＰ３５０／ＬｉＡｓＦ＿６和ＣＰ３５０／ＬｉＰＦ＿６的离子传导性能,给出了与复阻抗谱相对应的等效电路．离子电导率随［Ｌｉ］／［ＥＯ］的变化而出现一极大值,室温下,两体系电导率极大值分别为１．３８×１０（－４）,８．３２×１０（－５）Ｓ／ｃｍ．电导率随温度升高而增加．导电行为呈非－Ａｒｒｈｅｎｉｕｓ特征．阴阳离子半径之和（ｒ＿ｃ＋ｒ＿ａ）愈大,离子电导率愈高．     

一种梳状高分子固体电解质的分子运动和离子导电性

用交流复阻抗谱和动态粘弹谱等对交替马来酸酐共聚物多缩乙二醇酯衍生物及其ＬｉＣｌＯ４盐复合物进行了研究．结果表明，在Ｌｉ／ＥＯ＝０．０７—０．０４２范围内，从１７３Ｋ到３７３Ｋ，本聚合物一高氯酸锂复合体系的动态粘弹谱存在着两个明显的转变，其中β转变归属于ＰＥＯ的侧链玻璃化转变，转变温度随ＬｉＣｌＯ４盐浓度的增加而增加。α转变归属于主链玻璃化转变，在Ｌｉ／ＥＯ＝０．０２８时有极大值。盐浓度与电导率的关系与通常不一样，在所研究盐浓度范围内观察到两个峰，其一在Ｌｉ／ＥＯ＜０．０１４，另一峰在Ｌｉ／ＥＯ＝０．０２８．电导率与温度的依赖关系不符合Ａｒｒｈｅｎｉｕｓ行为；以ｌｇσ对１／Ｔ－Ｔ０作图，用侧链玻璃化转变温度Ｔβ作Ｔ０时，呈典型的ＶＴＦ行为。该体系室温电导率最高可达６×１０－６ｓ／ｃｍ．     

Amphiphilic polymer gel electrolytes. I. preparation of gels based on poly(ethylene oxide) graft copolymers containing different ionophobic groups

Amphiphilic graft copolymers were prepared via the radical copolymerization of poly(ethylene oxide) (PEO) macromonomers with fluorocarbon or hydrocarbon acrylates in toluene with 2,2′‐azobisisobutyronitrile (AIBN) as an initiator. ¹H NMR spectroscopy confirmed that the composition of the graft copolymers corresponded well to the monomer feed. For gel electrolytes prepared from the amphiphilic copolymers, the nature of the ionophobic parts of the amphiphilic graft copolymers had a great influence on the ion conductivity. Gel electrolytes based on graft copolymers containing fluorocarbon side chains showed significantly higher ion conductivity than electrolytes based on graft copolymers containing hydrocarbon groups. The ambient‐temperature ion conductivity was about 2.6 mS/cm at 20 °C for a gel electrolyte based on an amphiphilic graft copolymer consisting of an acrylate backbone carrying PEO and fluorocarbon side chains. Corresponding gels based on graft copolymers with PEO side chains and hydrocarbon groups showed an ambient‐temperature ion conductivity of about 1.2 mS/cm. The gel electrolytes contained 30 wt % copolymer and 70 wt % 1 M LiPF₆ in an ethylene carbonate/γ‐butyrolactone (2/1 w/w) mixture. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2223–2232, 2001     

Random binary brush architecture enhances both ionic conductivity and mechanical strength at room temperature

The ionic conductivity and the mechanical strength are two key factors for the performance ofpoly(ethylene oxide) (PEO) based polyelectrolytes.However,crystallized PEO suppresses ion conductivity at low temperature and melted PEO has low mechanical strength at high temperature.Here,random binary brush copolymer composed of PEO-and polystyrene (PS)-based side chains is synthesized.PEO crystallinity is suppressed by the introduction of PS brushes.Doping with lithium trifluoromethanesulfonate (LiTf) induces microphase separation.Due to a random arrangement of the brushes,the microphase segregation is incomplete even at high salt loading,which provides both high ionic conductivity and high mechanical strength at room temperature.These results provide opportunities for the design of polymeric electrolytes to be used at room temperature.     

燃料电池用聚合物质子交换膜的研究进展

质子交换膜（PEM）是质子交换膜燃料电池的核心组件之一,具有隔绝阴阳极、提供质子传递通道和阻止燃料渗透的作用. 商业化应用的全氟磺酸PEM存在燃料渗透严重、高温条件下导电性差和成本高的问题,开发性能优良的聚合物PEM显得很有必要. 本文讨论了近年来聚合物PEM的研究进展,分别从聚合物的主链、支链和交联结构角度介绍了分子结构对薄膜相分离、质子导电性、稳定性和电池性能等性能的影响,并讨论了聚合物分子结构设计方面存在的问题,最后对燃料电池用聚合物PEM在未来的发展方向进行了展望.     

含硅氢键聚二硅氧烷/聚醚共混聚合物电解质 II. PSEMH对PEO结晶性能及离子电导率的影响

通过Raman,DSC和XRD等方法对PEO-PSEMH-LiClO4全固态共混聚合物电解质进行了研究,结果表明PSEMH能够显著地降低PEO-LiClO4电解质体系的PEO的结晶性和玻璃化转变温度,同时PSEMH分子的二硅醚链节中氧原子与Li+间具有配位作用,从而大幅提高x%PEO-y%PSEMH-LiClO4电解质在低温区的离子电导率。而当PSEMH交联硫化之后,虽然降低了PEO的结晶度和Tg,但是由于PSEMH的交联网络限制了聚合物链段的运动性,使得电解质的离子电导率在低温区高于100%PEO-LiClO4(约为12倍),而在高温区则低于100%PEO-LiClO4,充分证明了PSEMH对电解质的离子电导率的具有显著的贡献作用。     

STUDIES ON ENHANCED CONDUCTIVITY OF STRETCHED CONDUCTING POLYMERS

A physical model of series of the conductivity on chain and the interchain conductivitybetween chains is proposed to explain enhanced conductivity of stretched conducting polymers.This model suggests that the enhanced conductivity for stretched conducting polymers might bedue to increasing of the interchain conductivity between chains along the elongation direction afterdrawing processes if the conductivity on chain is assumed much larger than that of the interchainconductivity between chains. According to this model, it is expected that the temperaturedependence of conductivity measured by four-probe method for stretched conducting polymers iscontrolled by a variation of the interchain conductivity between chains with temperature, whichcan be used to explain that a metallic temperature dependence of conductivity for stretchedconducting polymers is not observed although the conductivity along the elongation direction isenhanced by two or three orders of magnitude.     

侧链结构对磺化聚芳醚性能及微观形貌的影响

比较了3种主链结构相同而侧链结构不同的磺化聚芳醚(SPAE)材料的性能. 分析了侧链结构对聚合物的吸水、 溶胀及质子传导行为的影响. 结果表明, 在相同的离子交换容量(IEC)条件下, 具有柔顺脂肪族侧链的聚芳醚材料具有较高的质子传导率. 其原因是由于柔顺的脂肪族侧链比刚性的芳香族侧链更易运动, 有利于侧链末端磺酸基团的聚集, 进而形成离子簇. 3种聚合物微观形貌的分析结果表明, 含柔顺侧链结构的聚合物薄膜具有更大的质子传输通道, 其结果与聚合物的宏观吸水和传导现象相吻合.     

Novel siloxane polymers as polymer electrolytes for high energy density lithium batteries

A variety of disubstituted (double-comb) polysiloxane polymers have been prepared containing linear, branched, and cyclic oligoethyleneoxide units, –(OCH₂CH₂)_n–, in the side chains and as part of the siloxane backbone. Copolymers, using mixtures of linear ethylene oxide side chains, were also synthesized. These polymers were doped with LiN(SO₂CF₃)₂ (LiTFSI, 1) and conductivities of the polymer-salt complexes were determined as a function of temperature and doping level. The maximum conductivity of these polymers at 25 ° C was 2.99 ×10^–4, for a copolymer containing equimolar amounts of side chains with n = 5 and 6.     

Synthesis and properties of polyimides bearing acid groups on long pendant aliphatic chains

A series of novel polyimide electrolytes having long pendant sulfo‐ or phosphoalkoxy groups were synthesized for fuel‐cell applications. Sulfodecyloxy‐, phosphodecyloxy‐, and sulfophenoxydodecyloxy‐substituted benzidine monomers were synthesized from dihydroxybenzidine. These monomers were copolymerized with naphthalene tetracarboxylic dianhydride and fluorenylidene dianiline to give the corresponding polyimides. A flexible, ductile, and self‐standing membrane was obtained via casting from the polyimide solution. Because the acid groups were on long pendant side chains and away from the main chains, the polyimide membrane showed improved oxidative and hydrolytic stability in comparison with the polyimides with sulfonic acid groups on the main chains or on the short side chains. High thermal stability (no glass‐transition temperature and a decomposition temperature > 200 °C) was also obtained. The polyimide membrane displayed high proton conductivity of 10^?1 S cm^?1 at 120 °C. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3995–4005, 2006