导电高分子聚噻吩衍生物的研究进展

聚噻吩是研究最为广泛的功能高分子材料。介绍了烷基取代、带支链和杂原子取代的各类聚噻吩衍生物的结构和合成方法 ,以及其作为新型的导电高分子材料的电光学性能和应用研究     

导电高分子聚噻吩及其衍生物的研究进展

介绍了无取代、烷基取代和杂原子取代的导电高分子聚噻吩等衍生物的结构、单体的制备，概述了聚噻吩的化学聚合、电化学合成方法以及近几年新兴的紫外辐射及微波辐射促进合成方法，综述了聚噻吩作为新型的功能高分子材料的合成研究现状及发展前景。     

聚噻吩类衍生物电致发光材料研究进展

介绍了典型的具有光电性能的噻吩类导电高分子,包括烷基取代、侧链含杂原子取代以及与其他单体共聚的聚噻吩衍生物近年来的研究进展,对它们的制备、结构及发光性能进行了归纳、总结和评论,并对其今后的发展前景进行了展望。     

聚噻吩及其衍生物基复合材料研究进展

聚噻吩因其良好的溶解性、高电导率和环境稳定性成为导电高分子研究的热门领域之一。综述了聚噻吩及其衍生物基复合材料的研究进展及其制备方法(原位聚合法、电化学法、插层法、界面聚合法、乳液法和共混法等),介绍了聚噻吩类复合材料在电容器、电致变色和电磁方面的应用前景及现状,指出了聚噻吩及其衍生物基复合材料研究中普遍存在的易脱掺杂、电导率不高和性能不稳定等问题。     

共轭导电高分子/纳米纤维素复合材料研究进展

以纳米纤维素为基体材料、共轭导电高分子为功能材料,制备的共轭导电高分子/纳米纤维素复合材料兼具共轭导电高分子良好的导电性能以及纳米纤维素易改性、易成膜、可降解等优良特性,由此而拓宽了二者的开发与应用范围,并促进了导电高分子复合材料的发展。综述了几种典型的共轭导电高分子/纳米纤维素复合材料的研究进展,介绍了聚苯胺/纳米纤维素复合材料、聚吡咯/纳米纤维素复合材料和聚噻吩/纳米纤维素复合材料的制备及应用。     

聚噻吩及其衍生物、聚噻吩基复合材料的导电性能研究进展

综述了聚噻吩及其衍生物的化学结构、制备、聚合机理、导电机理、导电性能和聚噻吩基复合材料的导电性能的研究进展.已有研究表明,纯的聚噻吩及其衍生物的电导率比较低,一般可通过掺杂来提高其电导率.同时由于聚噻吩及其衍生物具有高的Seebeck系数以及低的热导率,因此若将其与无机热电纳米材料复合,将有望制备出热电性能优良的有机/无机的纳米复合材料.     

聚合工艺对聚噻吩固体片式铝电解电容器的影响

采用导电高分子材料聚(3,4-乙撑二氧噻吩)(PEDT)制备固体片式铝电解电容器,主要探索了化学聚合工艺对聚噻吩固体片式铝电解电容器性能的影响.结果表明,低的聚合溶液浓度可以提高所制备电容器的容量、降低损耗和等效串联电阻(ESR),但需要增加聚合次数以获得所需厚度的PEDT膜;化学聚合过程中烘干温度为40℃并进行适当次数的清洗,其所制备的产品容量较高,损耗较小,ESR低;增加聚噻吩的化学聚合次数可以提高电容器的容量引出水平,并降低损耗和ESR.     

溶胶-凝胶法制备PF-CaCO3预聚体功能性材料

将性能优良的纳米碳酸钙改性高分子材料-酚醛树脂制备酚醛树脂纳米复合材料,旨在得到一种可以取代部分价格昂贵的填充料及化学助剂,减少树脂的用量,节约能源等优点的一种功能性的填料。首先采用改性剂十二烷基甜菜碱制备纳米碳酸钙粉末,并通过添加入自制的酚醛树脂胶黏剂中,进而通过扫描电子显微镜(SEM)、红外光谱分析(FT-IR)、差示扫描量热/热失重(DSC-TG)分析,表明十二烷基甜菜碱的添加量2.5mL(占溶液质量的5%)较好,且得到的PF-CaCO3预聚体均一,热稳定性好。     

π-共轭导电高分子材料的研究进展及存在问题

对新型共轭导电高分子材料的导电机理进行了分析，综合评述了聚对苯（ＰＰＰ）、聚吡咯（ＰＰＹ）、聚噻吩（ＰＴＨ）、聚苯胺（ＰＡｎ）和聚苯基乙炔（ＰＰＶ）的最新制备方法，并指出了共轭导电高分子目前存在问题及发展方向。     

多壁碳纳米管/聚甲基丙烯酸甲酯复合材料的结构与导电性能

采用超声波辅助溶液共混的方式制备多壁碳纳米管/聚甲基丙烯酸甲酯复合材料,采用扫描电镜及广角X衍射仪对复合材料的微观相态结构进行了分析,对复合材料的物理机械性能及导电性能进行了测试.结果表明:采用溶液混合并用超声辅助分散的方法可使纳米多壁碳纳米管在PMMA基体中分散良好,在碳纳米管含量较低的情况下就可以获得导电性能及物理机械性能良好的复合材料.     

Enhanced pervaporative desulfurization by polydimethylsiloxane membranes embedded with silver/silica core-shell microspheres

Pervaporative desulfurization based on membrane technology provides a promising alternative for removal of sulfur substances (as represented by thiophene) in fluid catalytic cracking (FCC) gasoline. The present study focused on the performance enhancement of polydimethylsiloxane (PDMS) membrane by incorporation of core-shell structured silver/silica microspheres. A silane coupling agent, N-[3-(trimethoxysily)propyl]-ethylenediamine (TSD), was used to chelate the Ag(+) via its amino groups and attach the silver seeds onto the silica surface via condensation of its methoxyl groups. The resultant microspheres were characterized by Zeta-positron annihilation lifetime spectroscopy (ZetaPALS), inductively coupled plasmaoptical emission spectrophotometer (ICP), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The Ag(+)/SiO(2)-PDMS composite membranes were prepared by blending PDMS with the as-synthesized silver/silica microspheres. PALS analysis was used to correlate the apparent fractional free volume with permeation flux. The sorption selectivity towards thiophene was enhanced after incorporation of silver/silica microspheres due to the π-complexation between the silver on the microsphere surface and the thiophene molecules. The pervaporative desulfurization performance of the composite membrane was investigated using thiophene/n-octane mixture as a model gasoline. The composite membrane exhibited an optimum desulfurization performance with a permeation flux of 7.76 kg/(m(2)h) and an enrichment factor of 4.3 at the doping content of 5%.     

The effect of zeolite L content on dielectric behavior and thermal stability of polyimide thin films

Zeolite L, with the ratio Si/Al?=?4, was prepared by hydrothermal method and used to obtain composite films based on a polyimide matrix having pendant carboxylic groups. The effect of zeolite L content on dielectric behavior and thermal stability of polyimide thin films was studied. The films were prepared by casting a suspension resulting from direct mixing of a poly(amic acid) (PAA) solution and zeolite L particles onto glass plates, followed by thermal imidization under controlled temperature conditions. The PAA was synthesized by solution polycondensation of a mixture of two diamines, 3,5-diaminobenzoic acid and 2,2-bis[4-(4-aminophenoxy)phenyl]propane (molar ratio 1:3), with 4,4′-oxydiphthalic anhydride, using N-methyl-2-pyrrolidone as solvent. To improve the compatibility between organic and inorganic phases, the surface of zeolite particles was modified by treating with 3-aminopropyltriethoxysilane. The surface morphology of the composite films investigated by scanning electron microscopy showed good compatibility between filler and polymer matrix. The films were flexible, tough, and exhibited high-thermal stability, having the initial decomposition temperature above 450?°C. Dynamic mechanical analysis and dielectric spectroscopy revealed sub-glass transitions, γ and β, and an α relaxation corresponding to the segmental motions above the glass transition temperature. The values of the dielectric constant at 10?kHz and 200?°C were in the range of 3.3–4.2.     

纳米材料对阔叶纤维素包装膜性能影响的研究

采用NMMO法,以阔叶纤维素为原料制备纤维素膜,通过向铸膜液中添加经硅烷偶联剂KH-550改性的纳米SiO2,钛酸酯偶联剂改性的CaCO3以及载银TiO2材料制备纳米／纤维素复合膜。对制备纳米／纤维素复合膜微观结构采用原子力显微镜（AFM）和扫描电子显微镜（SEM）进行了表征,并结合力学性能和透氧性能测试分析了纳米材料结构和含量对膜综合性能的影响。结果表明：纳米材料的加入可以改善NMMO法纤维素膜的透氧性能,当改性纳米SiO2、改性纳米CaCO3和载银TiO2添加质量分数分别为2％、1％和1．5％时制备的纤维素纳米复合薄膜的综合性能达到最优。     

溶胶凝胶法制备具有介孔结构的聚酰亚胺/SiO_2多孔复合微球

采用反相乳液法,以水溶性聚酰胺酸三乙胺盐(PAAS)、正硅酸乙酯(TEOS)为前驱体,通过溶胶凝胶法制备了具有介孔结构的聚酰亚胺(PI)/SiO_2多孔复合微球。将PAAS水溶液和TEOS水解液的混合溶液在液体石蜡中形成反相乳液,TEOS经水解缩合形成无机三维骨架,通过化学酰亚胺化使复合体系中的PAAS转变为PI,成功制备了含有介孔结构的PI/SiO_2多孔复合微球。研究发现,随着SiO_2含量的增加,复合微球的规整性不断提高,其比表面积由20.5 m~2/g增加至521.8 m~2/g。同时发现,调节TEOS水解液的pH值,微球的比表面积也会发生相应的变化。此外,热重分析结果显示该复合微球的热分解温度超过500℃,表明其具有优异的热稳定性。     

聚酰亚胺/LTNO复合膜介电性能及其影响因素

采用溶胶-凝胶法合成出Li和Ti改性的氧化镍(LTNO)粒子,并通过前体溶液共混法首先制备聚酰胺酸/LTNO前体膜,再经亚胺化得到高介电常数聚酰亚胺/LTNO复合膜。研究发现,复合膜的介电性能可以通过调节LTNO的含量以及Li和Ti在LTNO中的比例来进行调控。选用按Li、Ni和Ti的摩尔百分比为0.30∶0.68∶0.02制备的LTNO粒子做填料,当其体积分数为0.4时,复合膜在100 Hz电场中的介电常数可以达到570。     

聚酰亚胺/纳米Al_2O_3三层复合薄膜的制备

将掺杂纳米Al2O3的聚酰胺酸与未掺杂聚酰胺酸在玻璃板上逐层涂膜,热亚胺化制备了3层聚酰亚胺/纳米Al2O3复合薄膜.采用扫描电镜(SEM)对该薄膜的微观形貌进行了表征,测试了薄膜的热稳定性、力学性能及电击穿场强.结果表明,复合薄膜的热性能及电击穿场强均高于掺杂薄膜及未掺杂膜,当热失重达到10%时,复合薄膜的热分解温度达到了629.1℃;与掺杂薄膜相比,复合薄膜的力学性能得到明显提高,拉伸强度和断裂伸长率分别为117.4 MPa和18.5%.     

Electrospun polyimide/titanium dioxide composite nanofibrous membrane by electrospinning and electrospraying

Fibrous membrane with a fibre diameter of 229 +/- 35 nm was fabricated from polyimide solution by electrospinning. Nanofibrous membrane with a fibre diameter of 251 +/- 37 nm was fabricated by combined electrospinning and electrospraying for polyimide/TiO2. Among the different solvents studied, ethanol was the effective solvent for dispersing the TiO2 nanoparticles in the nanofibrous matrix during electrospraying. The average pore size of polyimide membrane was obtained in the range 0.79-0.89 microm whereas the average pore size of polyimide/TiO2 membrane was found to be in the range 1.23 microm. The tensile stress of polyimide nanofibrous membrane and also polyimide/TiO2 composite fibrous membrane determined to be 0.36 MPa and 0.65 MPa respectively. Nanofibrous membrane containing TiO2 nanoparticles on the surface of the polyimide nanofibres improved the mechanical stability of the membrane.     

基于复合纳米颗粒的有机-无机杂化膜制备与性能表征

采用共混杂化的方法,利用Al2O3/TiO2复合纳米颗粒对疏水性强、易污染的聚偏氟乙烯膜进行改性,以增强其在水相溶液中的应用能力。通过测定纯水通量、截留率和膜表面接触角分别考察膜的透过、分离性能及亲疏水性能。用扫描电镜观察杂化膜的表面形态及断面结构。用傅立叶红外光谱分析杂化膜的化学结构,用X射线衍射分析杂化膜的结晶状态。膜的抗污染性能由料液通量试验考察。改性前后膜的测试结果表明,纳米颗粒的加入改善了聚偏氟乙烯膜的通量、亲水性能和抗污染性能。     

剥离型纳米蒙脱土/聚酰亚胺复合材料的制备与表征

利用二苯基甲烷-4,4’-二异氰酸酯（MDI）与酸化的蒙脱土（MMT）表面的羟基进行反应制得了MMT-MDI;进一步利用己内酰胺（CPL）对MMT-MDI进行插层并对多余的异氰酸酯端基进行封端,制得了MMT-MDI-CPL。采用预聚体溶液插层法,利用聚酰胺酸（PAA）在二甲基乙酰胺（DMAC）溶剂中分别对MMT-MDI和MMT-MDI-CPL进行预聚体插层,制得了剥离型纳米MMT/聚酰亚胺（PI）复合材料。通过电感耦合等离子体发射光谱（ICP-OES）、FTIR、TG、XRD和SEM对改性MMT和纳米MMT/PI复合材料进行了表征。结果表明：MDI与MMT表面羟基反应而被成功接枝于MMT上;MDI对MMT的改性、CPL对MMT-MDI的插层和封端使MMT层间距得到逐步扩大;MMT/PI复合材料的XRD和断面SEM表明,MMT在PI基体中得到了充分剥离。     

Synthesis and properties of new polyimide/clay nanocomposite films

A series of polymer–clay nanocomposite (PCN) materials consisting of polyimide and typical clay were prepared by solution dispersion. Quaternary alkylammonium modified montmorillonite, Cloisite 20A, was used as organoclay. Poly(amic acid) solution was prepared from the reaction of benzophenone-4,4′,3,3′-tetracarboxylic dianhydride and 2-(5-(3,5-diaminophenyl)-1,3,4-oxadiazole-2-yl) pyridine in dimethylacetamide. Thermal imidization was performed on poly(amic acid)/organoclay dispersion in a regular temperature-programmed circulation oven. The study of interlayer d-spacing with X-ray diffraction pattern indicates that an exfoliated structure may be present in the nanocomposite 1%. Intercalated structures were obtained at higher organoclay loadings. Nanocomposites were studied using thermogravimertic analysis and differential scanning calorimetry. Nanocomposites exhibit higher glass transition temperature and improved thermal properties compared to neat polyimide due to the interaction between polymer matrix and organoclay particles. The results are also compared with data of a similar work. Morphology study with scanning electron microscopy showed that the surface roughness in nanocomposite 1% increased with respect to pristine polyimide. Solvent uptake measurements were also carried out for the prepared materials. Maximum solvent adsorption was observed for dimethyl sulfoxide (DMSO). It was found that the solvent uptake capacity decreased with increasing clay content.