Structure and electric conductivity of copolymers of aniline and aniline-2-sulfonic acid obtained via chemical oxidative copolymerization

A method for the synthesis of aniline-aniline-2-sulfonic acid copolymers is developed. It is shown that the sulfonated polyaniline is capable of self-doping, as evidenced by higher stabilities of the structure and electric conductivity of the copolymers than those of the homopolymer. The mechanism of electric conductivity of the copolymers depends on the comonomer ratio in the feed. By means of the method of impedance spectroscopy, it is found that a decrease in electric conductivity with an increase in the degree of sulfonation is primarily due to reduction in the order of the copolymer structure.     

Partially sulfonated polyaniline: conductivity and spectroscopic study

Polyaniline and set of copolymers of aniline with orthanilic acid (OA) were prepared by oxidation of monomers with ammonium peroxydisulfate. Amount of OA in mixture of comonomers was varied from 0 to 10%. The higher amount of OA resulted in decrease of conductivity and increased steepness of temperature dependence of conductivity. The X-ray photoelectron spectroscopy showed content of self-doping groups in surface layer slightly higher than expected from the feed ratio of comonomers. Shifts of positions of bands of ring stretching vibrations towards their position in polyaniline base and shift of the band of protonated units Q=NH⁺–B or B–NH^+?–B in the FTIR spectra observed with increasing amount of OA have shown increase of electron localization in copolymers. Finally, Raman spectroscopy proved that sulfonic groups act as structural defects in polymer’s geometry. Polarons are expected to be localized on short isolated segments between the structural defects.     

苯胺乳液聚合条件的研究

以（ＮＨ４）２Ｓ２Ｏ８为氧化剂、在非极性溶剂－功能质子酸－水三相体系中,采用乳液聚合方法合成聚苯胺乳液和粉末。对乳液聚合与化学氧化溶液聚合合成的聚苯胺性能进行了比较,研究了掺杂酸、氧化剂、反应时间、温度和水相浓度等聚合条件对聚苯胺导电性、溶解性、乳液粘度等性能的影响。结果表明,乳液聚合产率大于８０％,聚苯胺电导率大于１Ｓ／ｃｍ,在有机溶剂中的溶解性与用化学氧化合成的聚苯胺相比有明显提高。     

Electropolymerization of 2-aminophenylboronic acid and the use of the resulting polymer for determination of sugars and oxyacids

Electropolymerization of aminophenylboronic acids proceeds by the mechanism typical of conducting polyaniline, if the substituent in the ring is the electron donor and its position favors the electrophilic substitution into the para position with respect to the amino group in the ring. For the same reason, the polymerization of meta-aminophenylboronic acid requires the presence of fluoride ions to transform the weak electron acceptor, boronic acid group into the electron-donating trifluoroborate anion. It is shown that electropolymerization of ortho-aminophenylboronic acid can be carried out in strongly acidic media in the absence of fluoride ions, in analogy to unsubstituted polyaniline. The conductivity of the resulting polyanilineboronic acids synthesized under optimal conditions increases upon their binding with sugars and oxyacids, which allows detecting the specific interactions only, while the nonspecific interactions lower down the polymer conductivity.     

Conductivity and flame retardancy of polyaniline-deposited functional cellulosic paper doped with organic sulfonic acids

Two kinds of organic sulfonic acids, i.e., p-toluenesulfonic acid (PTSA) and sulfosalicylic acid (SSA), were used as doping acid to prepare the polyaniline-deposited functional cellulosic paper, and both the conductivity and flame retardancy of the functional cellulosic paper were investigated. The results indicated that both the conductivity and the flame retardancy of the paper composite had a close relationship with the incorporation of doping acid. Both the conductivity and the oxygen index (OI) value increased with the increase of the acid concentration. SSA performed much better than PTSA and the inorganic acids studied previously for both the conductivity and the OI value of functional cellulosic paper. The conductivity of the paper doped with SSA was more stable than that of the paper doped with PTSA, and the OI value only decreased about 1 % within 40 days for the functional cellulosic paper doped with the two doping acids. Compared with the polyaniline-deposited paper doped with PTSA, both the much higher doping level and the much smaller and more compact polyaniline particles deposition were probably responsible for the significantly better conductivity and flame retardancy of the polyaniline-deposited paper doped with SSA.     

Modified polyaniline through simultaneous electrochemical polymerization of aniline and metanilic acid

Simultaneous electropolymerization of aniline and metanilic acid in aqueous HClO₄ leads to a copolymer similar to that obtained by direct sulfonation of polyaniline. Characterization by electrochemical and spectroscopic methods (UV -visible, Fourier transform IR and proton NMR) indicated the presence of polyaniline linear chains in which metanilic acid units were inserted as spacers. Elemental analysis showed that the copolymer was 40% doped by the sulfonate side-groups intramolecularly (self-doping) and 20% doped by ClO₄⁻ intermolecularly. The presence of sulfonate functional groups decreased electronic conductivity and increased solubility in alkaline solvents, but the electtrochemical properties remained principally that of polyaniline.     

On the catalytic oxidation of ascorbic acid at self-doping polyaniline films

Ascorbic acid molecules in either acid or conjugate base forms have been oxidized on self-doping carboxylated polyaniline thin films. The kinetic model proposed by Bartlett et al. has been successfully applied to the catalytic reactions. Active sites in the polymer have been identified as the rings having quinoid character. The existence of significant electrostatic repulsions between ionogenic groups at the self-doping polymer and negatively charged ascorbate molecules has been established thanks to the analysis of the pH dependence of the Michaelis constant. It has been found that in contrast to inorganic conductors the regeneration of active sites in polyaniline-based materials is slower at higher potentials. Such a behavior can be satisfactorily correlated with the potential dependence of the polymer electronic conductivity.     

二磺酸掺杂高热稳定性导电聚苯胺的合成及性能

以有机二磺酸作为掺杂剂合成了具有高热稳定性的二磺酸掺杂导电聚苯胺。研究了反应时间、温度、酸/苯胺摩尔比等因素对产率、产物的导电率与分子量的影响。利用微波加热的方法测试有机二磺酸掺杂聚苯胺的热稳定性能，结果表明：有机二磺酸掺杂的导电聚苯胺在微波场中升温速率快，并且具有良好的反复升温性能。     

Structural effects of dopants and polymerization methodologies on the solid‐state ordering and morphology of polyaniline

The solid‐state three‐dimensional ordering of polyaniline–dopant complexes was investigated with four structurally different sulfonic acid dopants. The doped materials were produced in three different ways: polyaniline emeraldine base doped with sulfonic acid (aqueous route), in situ polymerization at the organic–water solvent interface (interfacial route), and in situ polymerization in organic and aqueous solvent mixtures (bilayer route). p‐Toluenesulfonic acid (PTSA), 5‐sulfosalicilic acid (SSA), camphorsulfonic acid (CSA), and dodecylbenzene sulfonic acid (DBSA) were employed as dopants. The conductivity of the aqueous‐route samples showed 10 and 100 times higher conductivity than the interfacial and bilayer routes, respectively. WXRD studies suggested that the crystallinity of the doped samples was dependent on both the structure of the dopants and the polymerization techniques. DBSA increases the polyaniline interplanar distance and produced highly crystalline materials via the aqueous and bilayer routes but failed with the interfacial route because of poor solubility in water. CSA, PTSA, and SSA produced highly crystalline samples by the interfacial route but failed with the aqueous (except for CSA) and bilayer routes. SEM analysis revealed that the doped materials of the interfacial route had excellent continuous morphology and uniform submicrometer‐size particle distributions in comparison with those of the aqueous and bilayer routes. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1321–1331, 2005     

ANALYSIS AND CHARACTERIZATION OF MICROSCOPIC MORPHOLOGY AND ORIENTATION STRUCTURE OF POLYANILINE POLYMERIZED IN A CONSTANT MAGNETIC FIELD

Conductive polyaniline(PAn-_M and PAn-_O) doped with dodecylbenzene sulfonic acid(DBSA) was synthesized by using emulsion polymerization method in the presence of a constant magnetic field(0.4 T) and the absence of magnetic field, respectively.The effects of magnetic field on the microscopic morphology and orientation structure of PAn were generally analyzed and characterized by using transmission electron microscope(TEM),X-ray diffraction(XRD) and through the conductivity anisotropy of unit resistance o...     

磺化酚酞型聚醚砜膜的制备及其阻醇和质子导电性能

直接甲醇燃料电池 (Directmethanolfuelcell,DMFC)以高效、清洁和燃料储运方便等优点适宜于作为各种用途的可移动动力源 ,成为 2 0世纪 90年代以来研究与开发的热点[1,2 ] .目前 ,这种电池的研究难点主要集中在催化剂不稳定和质子交换膜透醇上 .一张好的DMFC膜不但要可传递质子、绝缘电子 ,还应具有良好的阻醇性能 .如果膜的阻醇性能不好 ,甲醇会穿过膜到达阴极 ,与氧直接反应而不产生电流 ,不但造成燃料的浪费 ,同时也影响阴极的正常反应 ,使电池效率下降[3 ] .目前广泛应用于燃料电池中的Nafion 系列膜是由美国DuPont公司生产的一种…     

Transport property of polyaniline and its molecular weight dependence

Ｔｈｅｅｌｅｃｔｒｉｃａｌｃｏｎｄｕｃｔｉｖｉｔｙ(σ)ｏｆｐｏｌｙａｎｉｌｉｎｅ(ＰＡｎ)ｄｏｐｅｄｗｉｔｈｉｎｏｒｇａｎｉｃｐｒｏｔｏｎｉｃａｃｉｄｓｉｓａｂｏｕｔ10Ｓ/ｃｍａｎｄσ(Ｔ)∝ｅｘｐ[-(Ｔ0/Ｔ)1/2].Ｉｔｍｅａｎｓｔｈａｔσｉｎｃｒｅａｓｅｓｗｉｔｈｉｎｃｒｅａｓｉｎｇｔｅｍｐｅｒａｔｕｒｅａｎｄｔｈｅｔｒａｎｓｐｏｒｔｐｒｏｐｅｒｔｙｉｓｉｎａｃｃｏｒｄａｎｃｅｗｉｔｈｔｈｅｖａｒｉａｂｌｅｒａｎｇｅｈｏｐｐｉｎｇ(ＶＲＨ)ｍｏｄｅｌ[1].Ａｆｔｅｒｓｔｒｅｔｃｈｉｎｇ,ｔｈｅＨＣｌｄｏｐ…     

SYNTHESIS AND CHARACTERIZATION OF A NOVEL DOPANT (C3-ABSA) FOR SYNTHESIZING TUBULAR POLYANILINE*

 4-(3-(4-((4-Nitrophenyl)azo)phenyloxy)propyl)aminobenzene sulfonic acid (C3-ABSA) was synthesized by the reaction of 3-bromide-l-(4-((4-nitrophenyl)azo)phenyloxy)propane (B3) with sodium p-aminobenzene sulfonic acid (ABSA)and acidification with hydrochloric acid. The C3-ABSA was characterized by FTIR, ¹H-NMR and second ion mass spectrum (SIMS). The molecular formula of dehydrated C3-ABSA was estimated to be ca. C_{21H20O6N4S by SIMS. Its decomposition temperature was measured by TGA to be ca. 232℃. It was found that tubular polyaniline (PANI) with a conductivity of 1.1 S/cm at room temperature was successfully synthesized by in-situ doping polymerization in the presence of C3-ABSA as a dopant.}     

一步乳液聚合法制备高溶解性导电聚苯胺

报道了一种高溶解性导电聚苯胺(PANI)的制备方法,以聚2-丙烯酰胺-2-甲基丙磺酸(PAMPS)作为掺杂酸和乳化剂,利用其特有的长链、亲水性及强酸性基团效应,通过乳液聚合法一步合成出具有较高溶解性的导电聚苯胺。利用核磁共振光谱仪(NMR)、傅里叶红外光谱仪(FT-IR)和扫描电子显微镜(SEM)等技术手段对产物结构和性能进行了表征分析。结果表明,在m(苯胺)∶m(AMPS)∶m(APS)=1∶2∶1.5;AMPS质量分数为20%;APS质量分数为30%;反应时间为5 h;反应温度为5℃的条件下,聚苯胺的产率高达86%,在有机溶剂二甲基甲酰胺(DMF)中的溶解度可达0.3814 g/g,在水中的溶解度可达0.2123 g/g,电导率达5.9 S/cm。     

Precipitation polymerization of aniline in the presence of water‐soluble organic acids

The precipitation polymerization of aniline in the presence of organic acids, including toluene‐4‐sulfonic acid, phenylphosphonic acid, 4‐aminophenylphosphonic acid, and acetophosphonic acid, led in one step to conductive polyaniline. The polyaniline showed very good affinity for water and was easily modified to be water‐soluble. In comparison with the widely studied postpolymerization of doped polyaniline, this reaction allowed reasonably good conductivity to be achieved at a lower acid/polyaniline ratio. Moreover, the easy in situ incorporation of the dopant into the polymer structure caused high stability of the created salt; that is, no dedoping was observed after it was washed with water, methanol, or other solvents. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3562–3569, 2002     

后磺化法精确可控合成主链型磺化聚苯喹喔啉及其质子交换膜性能研究

以不同摩尔比的4,4′-双(4-(2-苯基乙二酮基)苯氧基联苯、4,4′-双(2-苯基乙二酮基)二苯醚与3,3′,4,4′-四氨基联苯共聚制备聚喹喔啉,经后磺化法得到一系列磺化度可控的磺化聚苯基喹喔啉(SPPQ).模型化合物确认,磺酸基团精确接入电子云密度较高的含醚键的联苯片段的2,2′-位上,证明通过单体分子结构设计与后磺化法结合,可使磺酸基团在温和条件下,按预想接入到聚合物主链上,达到磺化度和磺化位置精确可控的目的. SPPQ的相对黏度均在3.8 dL/g以上.通过溶液涂膜法制备的主链型磺化聚苯基喹喔啉质子交换膜(SPPQ PEM)的吸水率都低于39%,尺寸变化率为2.1%~13%,且随着IEC和温度的提高而线性增加.如,80℃下,IEC高达2.21 meq/g的SPPQ-5的膜面和膜厚方向的尺寸变化率仅为11%和13%,具有良好的形状维持能力.热重分析表明,SPPQ PEM在320℃左右脱去磺酸基团,550℃左右发生聚合物主链降解,具有良好的热稳定性. Fenton试剂测试表明,SPPQ PEM开始破碎的时间随IEC的增加而缩短,在20℃时,IEC较低的SPPQ-1 (1.29 meq/g)破碎时间可达151 h,而IEC较高的SPPQ-5(2.21 meq/g)破碎时间缩短至81 h. PEM的质子传导率随温度和IEC的增加而显著提高,最高可达64 mS/cm,由于磺酸基团和喹喔啉酸碱对的形成以及吸水率偏低的原因,这一数值远低于Nafion.     

Electrochemical and chemical synthesis of nanostructure copoly(aniline-o-anisidine-o-toluidine) and study of its electrochemical behavior in organic sulfonic acid media

Terpolymerization of aniline, o-anisidine and o-toluidine was carried out by electrochemical and interfacial chemical polymerization. All homopolymers and terpolymer thin films have been synthesized through electropolymerization at room temperature in aqueous solutions containing 0.5 M of organic sulfonic acid, such as p-toluene sulfonic acid, methane sulfonic acid, sulfosalicylic acid, dodecylbenzene sulfonic acid, and 0.1 M of aniline, o-anisidine and o-toluidine monomers, using cyclic voltammetry method, applying a sequential linear potential scan at a rate of 25 mV s^?1 between ?0.1 and 0.9 V. The electrochemical terpolymerization has been performed at various mole ratios of monomers. Nanoparticles obtained from conjugation of homo- and terpolymer with organic sulfonic acids, were prepared by a chemical oxidation via interfacial chemical polymerization. SEM micrographs, FTIR spectra and conductivity measurements using four-probe method were applied for the characterization of the products. Terpolymer was characterized by higher conductivity than poly-o-toluidine and lesser than polyaniline and poly-o-anisidine. The solubility of terpolymers was dependent on the monomers mole ratio.     

Molecular assembled crosslinked self-doped polyaniline nano-thin films in application of electrochromic devices

Crosslinked self-doping polyaniline (SPANI) nano-thin films were prepared by using the molecular assembly process coupled with the copolymerization of aniline (AN) with the self-doping monomers DABSA (2,5-diaminobenzenesulfonic acid). DABSA were also used as surfactants and the di-amino groups rendered as chain extension/crosslinked sites in the simultaneous copolymerization and molecular assembly process. TEM and SEM results indicated that the morphology changes from micelles to nano-films. This SPANI nano-film is promising for the application in electrochromic devices.     

Composites of Polystyrene Sulfonic Acid (PSSA)‐Polyaniline and Montmorillonite Clay: Synthesis and Characterization

Polystyrene sulfonic acid (PSSA) doped water‐soluble polyaniline (PANI)/montmorillonite (MMT) clay composites were synthesized by intercalation polymerization in aqueous medium. The properties of the composites were characterized by X‐ray diffraction (XRD), transmission electron microscope (TEM), Fourier‐transform infrared spectroscopy (FT‐IR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X‐ray photoelectron spectroscopy (XPS) and conductivity measurement. The results show that the composite has a mixed nanomorphology and exfoliated silicate nanolayers of MMT clay dispersed in the polyaniline matrix. This composite is more thermal stable than that without clay samples and results in good stable temperature‐dependent dc conductivity [σ_dc(T)] as temperature changed.     

侧链含酞菁铜功能基的聚苯胺的制备与性能研究

以酞菁铜、氯磺酸和氯化亚砜为原料合成酞菁铜磺酰氯,并将其与本征态聚苯胺进行反应,合成了侧链悬挂酞菁铜功能基的聚苯胺(PAnCuPc).用元素分析、红外光谱和紫外-可见吸收光谱对产物和反应中间体进行了结构表征.PAnCuPc可溶于强极性非质子溶剂.如NMP,DMF,DMSO和DMAc,甚至在常用的低沸点溶剂如THF和三氯甲烷中也有一定的溶解性.红外光谱研究表明,与本征态聚苯胺相比,侧链含酞菁铜功能基的聚苯胺的吸收峰向低频方向移动.紫外-可见吸收光谱表明,侧链悬挂酞菁铜功能基的聚苯胺在可见光区和近红外区都具有较强的吸收.透射电镜和X射线衍射研究表明,该产物具有较强的结晶性能.