高民导吡咯聚合物在固体电解电容器中的应用

本文简要介绍两种新型电容器的制造工艺和性能等，期待这个新技术在我国能得到推广应用。

聚吡咯甲烯类聚合反应的动力学研究

采用原位紫外分光光度法研究了吡咯与苯甲醛、对二甲氨苯甲醛、香草醛及对硝基苯甲醛反应生成聚吡咯甲烯类聚合物过程中的合成反应机理 .研究表明 ,聚吡咯甲烯的合成反应为一零级反应 ,其反应速率与催化剂的酸度有关 ,而与吡咯和醛的浓度无关 .苯环上吸电子基团的存在有利于聚合反应的进行 ,较大空间位阻基团的存在则使聚合反应的速率下降 .

铂支撑的碘-聚吡咯修饰双层脂膜的I-V特性

首次在铂丝新生表面上形成了碘-聚吡咯双层脂膜,用循环伏安法研究了碘掺杂浓度对双层脂膜I-V特性的影响。用此法所得到的铂支撑双层脂膜十分稳定,可进一步用于生物传感器及分子电子器件的基础与应用研究。

聚吡咯层对聚酯/环氧树脂界面粘结性能的影响

采用吡咯化学沉积聚合方法对聚酯(PET)纤维进行表面改性,研究聚合工艺条件对纤维与环氧树脂界面剪切强度的影响.分别用SEM、共聚焦显微镜、DMA及单纤维拔出实验等测试手段对改性前后纤维的表面形貌、粗糙度、聚吡咯(PPy)与基体纤维大分子作用力及复合材料的界面剪切强度(IFSS)进行研究.结果表明:吡咯化学沉积聚合改性是一种有效提高纤维与树脂界面粘结性能的方法.此外,可进一步通过聚合改性工艺条件控制聚吡咯层的形貌及聚吡咯与基体纤维大分子的作用力,从而调控纤维与树脂界面剪切强度,吡咯气相化学沉积后再液相沉积,增强复合材料界面剪切强度比原纤维的提高了127.98%.

水杨酸分子印迹膜电化学传感器的制备

以水杨酸为模板分子,采用循环伏安法电聚合形成聚吡咯膜,以固定电位过氧化法去除印迹分子,制备了水杨酸分子印迹膜电极。本印迹电极能促进水杨酸电氧化过程,有效地避免结构类似物(如苯甲酸)对其测定的干扰。循环伏安法用于电化学检测,当富集时间为10min,磷酸盐缓冲溶液的pH=6.86时,在1.0×10-6～2.0×10-3mol/L浓度范围内,水杨酸氧化峰电流与其浓度呈良好的线性关系,检出限为0.8μmol/L,用分子印迹膜电极对加标样品进行分析,回收率为94.6%～103.4%。

Controlled Synthesis of PCL/PVP Copolymer by RAFT Method and Its HydrophUic Block-Dependent MiceUar Behaviors

A range of poly（ε-caprolactone）/poly（N-vinyl-2-pyrrolidone） amphiphilic block copolymers with well-defined hydrophilic chain length were synthesized by the living/controlled reversible addition fragmentation chain transfer polymerization method. The composition and struc- ture of the targeted resultants were characterized with 1H NMR, 13C NMR, FT-IR spec- troscopy and gel permeation chromatography. The various block copolymers were success- fully employed to fabricate the spherical micelle with core-shell morphological structure. The poly（N-vinyl-2-pyrrolidone） block-dependent characteristics of the copolymeric micelles were investigated by fluorescence spectroscopy, dynamic light scattering, and transmission electron microscopy. The solubilization of the hydrophobic ibuprofen as a model drug in the micelle solution was also explored. It was found that the drug loading contents are related to the micellar morphology structure determined by hydrophilic chain length in the copolymer.

侧链含自由基单元的1,4-吡咯并吡咯二酮共轭聚合物的合成和半导体性质研究

合成了两个侧链含有2,2,6,6-四甲基哌啶-1-氧自由基单元(TEMPO)的1,4-吡咯并吡咯二酮(DPP)共轭聚合物PDPP4T-1和PDPP4T-2,并开展了其半导体性质研究。薄膜场效应晶体管器件测试结果显示,相对于不含TEMPO的聚合物PDPP4T,PDPP4T-1和PDPP4T-2的场效应器件性能有所降低,不过,含TEMPO的聚合物器件性能最高仍达到了2.12cm2·V-1·s-1。进一步通过原子力显微镜和X射线衍射对TEMPO引入后导致性能降低的可能原因进行了研究。

Method for Control of Particle Size and Morphology of Paraffin/Polystyrene-Divinylbenzene Microcapsules

Microencapsulation of phase change materials(Micro PCMs) has been paid special attention because of their extensive applications in saving and releasing energy. Micro PCMs containing paraffin with a melting point of 55 ℃ in polystyrene-divinylbenzene(P(St-DVB)) were prepared by suspension-like polymerization. The characterization of microcapsules by FTIR, DSC and TG proved that paraffin had been successfully encapsulated and the proportion of encapsulated paraffin was 49.8%—58.5%. The effects of polyvinylpyrrolidone(PVP) with different molecular weights serving as the suspension stabilizer were investigated in detail. The results illustrated that the type of PVP had a significant influence on the particle size of Micro PCMs. The average diameter of Micro PCMs decreased with an increasing molecular weight of PVP. Moreover, the crosslinker-postaddition method was adopted in this study to improve the morphology of P(St-DVB) Micro PCMs. SEM images showed that when the DVB was added at the 2nd hour of polymerization the morphology of obtained P(St-DVB) Micro PCMs exhibited good sphericity since it could avoid the influence of cross-linker agent during the nucleation period.

Synthesis of PPy-like Nanocrystallines by Oriented Plasma Polymerization at Atmospheric Pressure

Polymeric polypyrrole-like （PPy-llke） nanocrystallines were fast synthesized through oriented plasma polymerization at atmospheric pressure and room temperature. The effects of discharge power on the nanocrystalline morphology were investigated. Larger power tends to produce longer nanocrystallines. 3 mm long nanowires were produced at the largest power in our experiment. TEM image and the sharp electronic diffraction spots in SAD suggest that the nanoparticles have a single crystal phase. The chemical structure of the nanocrystalline has been studied through FTIR, EDX etc. This novel polymerization method could have great applications in fabricating functional polymeric nanocrystallines.

Radiation-Induced Synthesis of Polyvinylpyrrolidone （PVP） Nanogels

Nanogels-particles of polymer gels having the dimensions in the order of nanometers-are gaining attention for their wide application as biomaterials. Mainly, the nanogels are promising novel pharmaceutical carriers for small biologically active agents, bin macromolecules and can be chemically modified to incorporate various ligands for targeted drug delivery. This important factor has stimulated research on dissimilar science field such as nanotechnology and biotechnology, polymer and materials sciences, biochemistry, radiation chemistry and pharmaceutical sciences. A multitude of techniques have been described for the synthesis of this nanomaterial from polymers. However, the use of ionizing radiation （γ, e-） has demonstrated to be especially suitable for obtaining polymeric nanogels with a high degree of purity for biomedical applications, although the gamma radiation has not been widely utilized for these purposes. The aim of this paper is to develop the synthesis of PVP （polyvynilpyrrolidone） nanogels by gamma irradiation, for their evaluation as potential pharmaceutical carriers. Experiments were performed using argon saturated solution of PVP （0.1-1%）. Crosstinking reactions were carried out in a gamma irradiation chamber with a 60Co source （ISOGAMMA LLCo）, at room temperature. The PVP concentration influence was evaluated in PVP solutions （0.1% and 0.25%） at 15 kGy. The SEM （scanning electron microscopy）, ATR （attenuate total reflection spectroscopy）, DLS （dynamic light scattering）, and viscosimetry were used as characterization techniques.

THE PREPARATION OF DOXORUBICIN-POLYVINYLPYRROLIDONE-NANOPARTICLES BY INVERSE EMULSION POLYMERIZATION

Doxorubicin-loaded nanoparticles, using doxorubicin （ADM） as model drug and vinylpyrrolidone as matrix, were prepared by inverse emulsion polymerization in the paper. The nanoparticles were characterized by telescope electron microscopy （TEM）, laser light scattering technique （LLS） and infrared spectrum （IR）. LLS test showed that the optimal prepared ADM-loaded nanoparticles had an average size 18.8nm and a narrow size distribution between 15nm and 32nm, which was consistent with the result obtained by TEM. And 1R results indicated that the nanoparticles consisted of ADM and polyvinylpyrrolidone （PVP）.

Synthesis of Silver Nanoparticle and Its Morphological Control

Silver nanoparticles with different morphologies were prepared in AgNO3 aqueous solution using nanocarbon as template medium and polymer surfactant as protecting agent in an ultrasonic field.The polymer surfactant polyvinylpyrrolidone(PVP)was self-prepared and used directly in aqueous solution form.The molecular weight of PVP was measured by viscosimeter.The crystalline phase,component,size,and morphology of the as-synthesized silver naoparticles were characterized by XRD,TEM,FTIR,and Laser Granularity Instrument.The results indicated that ultrasonic was the key factor to deoxidize Ag+ to be Ago,nanocarbon and polymer surfactants accelerated the deoxidization reaction course and controlled the agglomeration of freshly formed silver nanoparticles,the category of polymer surfactant had decisive effect on the morphology of as-synthesized nanoparticle.Well-defined dendrites silver nanoparticle could be attained when choosing PVP as surfactant in AgNO3 aqueous solution,while regular sphere silver nanoparticle could be synthesized in the presence of polyvinyl alcohol(PVA)surfactant.Moreover,the concentration of AgNO3 and ultrasonic action time also had obvious effect on the morphology of silver nanoparticle,low concentration of AgNO3 and long time of ultrasonic were not in favor of forming dendrite silver.

Kinetics of Copolymerization of Acrylonitrile with N-Vinylpyrrolidone in H_2O/Dimethyl Sulphoxide Mixture

Kinetics of copolymerization of acrylonitrile(AN) with N-vinylpyrrolidone(NVP) initiated by azodi-isobutyronitrile(AIBN) was investigated in H2O/dimethyl sulphoxide(DMSO) mixture between 50℃ and 70℃ under N2 atmosphere. The rate of copolymerization and particle size were measured respectively. The kinetic equation of copolymerization system is obtained as Rpat 60℃. The overall activation energy for copolymerization system was computed as 87.3kJ.mol-1. Effect of additives of hydroquinone and dioxane on copolymerization was discussed. The polymerization is retarded by hydroquinone and accelerated by dioxane, which confirms the free radical copolymerization of AN with NVP.

超级电容器用聚吡咯纳米粒子的比容量衰减机理研究

基于化学氧化聚合法制备了粒径约为40nm的掺杂对甲苯磺酸(TSA)的聚吡咯(PPy)复合纳米粒子.采用XRD、EDS、SEM和TEM研究了产物的结构和形貌特征,并用循环伏安、恒流充放电等方法测试了纳米粒子的电化学性能.结果表明PPy/TSA具有良好的快速充放电能力,在10 mA/cm2时比容量达到268Fg-1,但在1000次循环后发现其比容量下降了25.5%.用CV测试了PPy/TSA电极在第一次循环和第1000次循环的伏安曲线图,发现经过1000次循环后PPy/TSA电极的氧化峰逐渐消失,并且非法拉第电流减小.交流阻抗测试表明,PPy/TSA纳米粒子在反复充放电循环后,其界面电荷传递电阻增加,高频段双层电容值降低,但低频段的赝电容值却有所增加.通过比表面积测量发现,聚合物链的反复氧化-还原过程还可导致平均孔径减小、比表面积下降.红外和拉曼光谱也证实PPy纳米粒子在充放电过程中会发生降解,生成一种含氧的醌式结构,这表明聚合物电极材料比容量的下降可能与PPy主链的不可逆氧化和结构碎片化有关.

模糊聚合物可用于仿生学

密歇根大学的科学家称，他们开发出一种“模糊”聚合物表面，它可以改善电子植入物和活组织之间的界面，他们声称有可能使一种技术在某一天提高到使盲人能看见、使瘫痪者能行走。

Transparent conductive PVP/AgNWs films for flexible organic light emitting diodes by spraying method

In this study, a simple spraying method is used to prepare the transparent conductive films （TCFs） based on Ag nanowires （AgNWs）. Polyvinylpyrrolidone （PVP） is introduced to modify the interface of substrate. The transmittance and bending performance are improved by optimizing the number of spraying times and the solution concentration and controlling the annealing time. The spraying times of 20, the concentration of 2 mg/mL and the annealing time of 10 min are chosen to fabricate the PVP/AgNWs films. The transmittance of PVP/AgNWs films is 53.4%----67.9% at 380---780 nm, and the sheet resistance is 30 f~/n which is equivalent to that of commercial indium tin oxide （1TO）. During cyclic bending tests to 500 cycles with bending radius of 5 ram, the changes of resistivity are negligible. The performance of PVP/AgNW transparent electrodes has little change after being exposed to the normal environment for 1 000 h. The adhesion to polymeric substrate and the ability to endure bending stress in AgNWs network films are both significantly improved by introducing PVP. Spraying method makes AgNWs form a stratified structure on large-area polymer substrates, and the vacuum annealing method is used to weld the AgNWs together at junctions and substrates, which can improve the electrical conductivity. The experimental results indicate that PVP/AgNW transpar- ent electrodes can be used as transparent conductive electrodes in flexible organic light emitting diodes （OLEDs）.

Polypyrrole-cobalt-carbon nanocomposites as efficient counter electrode materials for dye-sensitized solar cells

In this work, we demonstrate a new kind of Pt-free counter electrode for dye-sensitized solar cells(DSCs). Polypyrrole-cobalt-carbon(PPY-Co-C) nanocomposites, with the advantages of low cost and simple preparation, show favorable catalytic activity in promoting tri-iodide reduction. The DSC composed of the PPY-Co-C nanocomposite electrode exhibits an acceptable energy conversion efficiency of 6.01%, a considerable short-circuit photocurrent of 15.33 mA cm-2, and a low charge-transfer resistance of 1.5 Ω cm2. The overall performance of PPY-Co-C is superior to the carbon counterparts and comparable with the platinum reference, rendering them efficient and promising counter electrode materials for DSCs.

Carbon-supported Fe/Co-N electrocatalysts synthesized through heat treatment of Fe/Co-doped polypyrrole-polyaniline composites for oxygen reduction reaction

In this paper,we synthesized cathode catalysts(PANI-PPYR,Fe/PANI-PPYR,Co/PANI-PPYR and Fe-Co/PANI-PPYR)with high performance oxygen reduction by using a simple heat treatment process.These catalysts were fabricated by directly calcining the Fe and/or Co doped polyaniline(PANI)-polypyrrole(PPYR)composites.Their electrocatalytic activity for ORR both in acidic and in alkaline media was investigated by voltammetric techniques.Among the prepared catalysts,Co/PANI-PPYR presents the most positive ORR onset potential of 0.62 V(vs.SCE)in 0.5 mol/L H2SO4 solution or?0.09 V(vs.SCE)in 1 mol/L NaOH solution.In addition,the Co/PANI-PPYR catalyst shows the largest limiting-diffusion current density for ORR,which is 4.3 mA/cm2@0.2 V(vs.SCE)in acidic and 2.3 mA/cm2@?0.3 V(vs.SCE)in alkaline media.In acidic media,a four-electron reaction of ORR on the Co/PANI-PPYR and Fe/PANI-PPYR catalysts is more dominant than a two-electron reaction.In alkaline media,however,a four-electron and a two-electron mechanisms are co-present for the ORR on all the prepared catalysts.Co/PANI-PPYR catalyst also presents good electrocatalytic activity stability for ORR both in acidic and in alkaline media.

Influence of surfactants on the morphology and photocatalytic activity of Bi_2WO_6 by hydrothermal synthesis

The flower-like microsphere Bi2WO6 with an average diameter of 2.5 μm is synthesized by a simple hydrothermal method in the presence of surfactant sodium dodecyl sulfate （SDS） or polyvinylpyrrolidone （PVP）. The crystalline phase, compositions, morphology, microstructure, surface area and band gap energy of the Bi2WO6 are characterized by X-ray diffraction, X-ray energy-dispersive spectrum, scanning electron microscopy, transmission electron microscopy and absorption spectra. It is found that surfactant has a significant influence on the microstructure and properties of the samples. The surfaetant SDS en- hances the surface area and photocatalytic activity of Bi2WO6, while the surfactant PVP has an opposite effect. Under Xe lamp irradiation, the Bi2WO6 sample prepared in the presence of SDS can degrade dye Rhodamine B （RhB） effectively.

Electrosynthsis of large polypyrrole films by multi-potential steps method

Polypyrrole (PPy) films were prepared by multi-potential steps polymerization in an aqueous pyrrole solution, with lithium perchlorate and oxalic acid as supporting electrolytes. Morphology and structure of PPy films were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Electrochemical behaviors of PPy films were studied by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The results show that multi-potential steps polymerization improves the conductivity of PPy films and large polymer films can be peeled off easily from the electrode without cracking. Lithium perchlorate and oxalic acid provide appropriate dopants for PPy polymerization. It was observed that the polymerization time and the current density have a crucial influence on the surface morphology of PPy films. Smooth and compact PPy films could be generated under long polymerization time and low current density. Multi-potential steps polymerization decreases the occurrence of peroxidation, which improves the conductivity of PPy films. The parameters for multi-potential steps polymerization have been optimized.