煤孔结构对煤/PAN复合材料导电性能的影响

煤基聚苯胺复合导电材料是利用煤的酸性官能团特征、孔结构特征和芳香层片特征 ,以煤为模板 ,用 APS引发苯胺单体 ,在煤中原位聚合而成的 .其中煤的孔结构是影响煤 / PAN导电性能的重要因素 .选择 HNO3 ,H2 O2 氧化及苯胺抽提的方法改变煤的孔结构 ;通过电导率及孔结构分析表明 ,氧化和抽提使煤的孔结构变得发达 ,因而苯胺能更好地进入已溶胀煤的孔结构中 ,提高了煤基聚苯胺的电导率 .     

国内期刊荟萃

煤基聚苯胺防腐蚀性能的研究邓宇强等.腐蚀与防护,2004,25(8):323聚苯胺对铁基金属具有优异的防腐蚀效果,开发聚苯胺防腐蚀涂料已成为防腐蚀涂料研究领域的一个新的研究热点。煤基聚苯胺利用煤的孔隙结构,分子筛结构和芳香层片结构,使苯胺溶胀在其中,然后引发原位聚合,从而制得导电率与聚苯胺相当的煤基聚苯胺。该煤基聚苯胺与纯聚苯胺相比具有聚合工艺简单、成本低等优点。本文采用加速浸泡和电化学测试方法,研究了煤基聚苯胺用于防腐蚀涂料中对碳钢的保护性能和效果。结果表明:①煤基聚苯胺在涂层中能起阳极保护作用的前提是其添加量要充…     

SF煤/聚苯胺导电复合材料结构表征

采用FTIR，X衍射和SEM等分析测试手段对在位聚合法制得的SF煤／聚苯胺导电复合材料的官能团结构、结晶性、外观形貌以及煤与聚苯胺之间的化学作用进行了分析，SEM分析发现，SF煤／聚苯胺复合物颗粒外型与SF煤相似，这表明聚苯胺是以SF煤为模板聚合的；FTIR分析表明，苯胺在聚合过程中和SF煤发生了化学作用，形成了更大的共轭体系；X衍射分析表明，苯胺在煤中聚合生成了较多低聚合度的聚苯胺晶粒，这些晶粒与SF煤发生了较为稳定的复合。     

煤基聚苯胺复合材料的导电性能研究

以煤为基体，不外加质子酸掺杂，制备了煤基聚苯胺复合导电材料，研究了其在不同条件下的导电性能。并对煤基聚苯胺合成反应后的废液进行了回收测试与循环利用研究。结果表明，在压力0．2～1．0MPa时，煤基聚苯胺的电导率随着压力的增大而增大；在30～120℃时，煤基聚苯胺的电导率随着温度的升高而减小；随着在环境中放置时间不同，煤基聚苯胺的电导率会有不同程度的变化；煤基聚苯胺聚合反应后的废液可以进行回收利用。     

煤/聚苯胺导电复合材料导电性能的研究

研究了在位聚合方法制得煤 /聚苯胺导电复合材料过程中引发剂量、质子酸浓度、聚合时间、聚合温度及煤样类型对该复合材料导电性的影响 ,结果发现 :所选煤样中 ,SF煤参与制得的煤 /聚苯胺复合材料电阻率降低最多 ,近十个数量级 .通过控制制备条件 ,可制得电阻率最低为 3.66Ω· cm的煤 /聚苯胺导电复合材料 .和纯聚苯胺相比 ,电导率下降不大 ,原料成本却下降 41 .2 % ,而且其最佳聚合温度易于控制 ,这为煤 /聚苯胺复合材料产业化提供了可能     

导电聚苯胺的合成与表征

采用微乳液聚合法,以苯胺为单体、十二烷基苯磺酸(DBSA)/盐酸(HCl)复合酸掺杂制备了导电聚苯胺,通过红外光谱对其结构进行了表征,考察了合成工艺条件对聚苯胺导电性能的影响,探讨了有机无机复合酸体系对聚苯胺热稳定性的影响。在复合酸十二烷基苯磺酸与盐酸物质的量比为3∶2、复合酸与单体物质的量比为2.0∶1、聚合温度为20℃、聚合时间为10h的优化条件下,所得到的掺杂态聚苯胺导电性能最佳。适当配比的有机无机复合酸掺杂后,导电聚苯胺的热稳定性显著提高。     

神府煤溶胀特性研究

研究了苯胺溶剂在不同时间、不同煤／溶比和不同温度等实验条件下对神府煤的溶胀，并用扩散理论对煤的溶胀过程进行了描述．结果表明，在溶胀时间为2h，煤／溶比为0．05，温度为80℃的溶胀条件下，神府煤在苯胺中的平衡溶胀度达到最大．溶胀动力学表明，煤的溶胀是受CaseⅡ扩散控制为主的过程．     

掺杂引发剂对聚苯胺和煤基聚苯胺导电性影响

以盐酸为掺杂剂、过渡金属盐为引发剂,制备了煤基聚苯胺(CPANI)和聚苯胺(PANI),探讨了掺杂引发剂及力化学作用对CPANI和PANI导电性能的影响,并研究了CPANI,PANI的红外光谱图.结果表明,在过渡金属盐的作用下,制备的CPANI,PANI具有一定导电性能,这表明过渡金属盐在一定程度上起到了引发苯胺单体聚合的作用,但相对过硫酸铵作为引发剂引发聚合的CPANI,PANI而言,导电性能有一定程度的下降.     

聚苯胺/PE复合材料的制备探究

采用原位化学氧化聚合法制备苯胺/PE导电复合材料,使苯胺在基体高分子PE的水溶液中进行聚合,研究反应体系中聚苯胺的含量、反应时间、温度对复合材料电导率的影响,确定了较佳的聚合反应条件,并且通过红外对光谱复合材料的结构、光电性能和稳定性进行了表征和分析。     

不同态煤基聚苯胺的结构与性能

采用溶液再掺杂法制备了DBSA二次掺杂态煤基聚苯胺(CBP-R-DBSA),得出较佳的二次掺杂条件:时间24 h,温度30℃,酸浓度1.2 mol/L,所得产物电导率为6.08×10-2 S/cm.分析探讨了煤基聚苯胺的掺杂-脱掺杂过程及不同态煤基聚苯胺的结构与性能,结果表明:原位聚合引入的外加酸与煤大分子酸对聚苯胺具有协同掺杂效应,煤基聚苯胺的掺杂-脱掺杂不完全可逆,煤表面酸性基团的掺杂作用相应减少了聚苯胺链上的掺杂活性点,这限定了DBSA对U-CBP的有效二次掺杂,其掺杂效果逊于乳液聚合原位掺杂.     

Microstructure,thermal and electrical properties of polyaniline/phenolic composite aerogel

Phenolic aerogel was first fabricated by sol–gel polymerization and freeze-drying method. Then, it was soaked into aniline solvent for 1 day. Ultimately, polyaniline/phenolic (PANI/RF) composite aerogel was obtained after the aniline molecules inside the phenolic aerogel were polymerized into polyaniline. The microstructure, thermal and electrical properties of the composites were investigated. The experimental results showed that polyaniline wires adhere to the surface of the micro holes skeleton which can be observed from the SEM images. Thus, polyaniline wires will form much smaller network inside the RF network, exhibiting an interpenetrating 3D network structure. In addition, compared with RF aerogel, PNAI/RF aerogel had maintained the thermal performance well, which showed mildly decline in heat-resistance and increase in heat conductivity, respectively. What’s more, it exhibited superior electrical performance (good specific capacitance) as compared with that of RF aerogel which is non-conducting, In general, PANI/RF aerogel with low heat conductivity (0.021 W/mK), high electrical conductivity (0.12 S/cm) and specific capacitance (280 F/g) exhibited more excellent comprehensive performance than single RF aerogel.     

Polymerization of Aniline Using Iron(III) Catalyst and Ozone,and Kinetics of Oxidation Reactions in the Catalytic System

The environmentally benign polymerization of aniline provided polyaniline with an emeraldine structure by using iron(III) and ozone which is easily converted from oxygen in air. The influence of the reaction temperature upon the molecular weight of the polyaniline in this system is different from that in the polymerization of aniline using ammonium peroxodisulfate as an oxidant. Although the polyaniline prepared here has low molecular weight, the low molecular weight of the polyaniline does not significantly influence the electrical conductivity of cast films. In contrast, this can provide an advantage for the engineering of polyaniline through solution‐processing. Kinetics of oxidation reactions in the polymerization, systematically investigated here, has revealed that polyaniline is produced catalytically in terms of iron(III) and that an oxidation reaction of iron(II) to iron(III) could be a rate‐determining step in the polymerization.     

溶胀对神华煤结构及液化性能的影响

采用甲苯和吡啶对中国神华煤进行直接液化前的溶胀处理,通过对溶胀度及抽提率的测定、IR光谱分析、热重分析以及溶胀煤的直接液化实验,探讨了溶胀预处理对神华煤结构及液化性能的影响.结果表明:经溶胀预处理,煤的溶胀度、抽提率获得了显著提高,煤结构中的弱共价键断裂,进而改善了其液化性能并提高了煤的直接液化转化率和油气产率.     

胜利煤的溶胀行为及溶胀煤的特性分析

为了考察溶胀作用对液化油煤浆黏度变化的影响作用,参照煤直接液化工艺条件,在四氢萘(THN)、N,N-二甲基甲酰胺(DMF)、液化起始溶剂(STA)和液化循环溶剂(REC)等不同有机溶剂中对胜利煤进行了溶胀行为研究。采用扫描电镜、孔隙比表面积分析仪、红外光谱仪等手段,研究了不同条件下胜利溶胀煤的表面性质变化。结果表明,胜利煤在极性溶剂N,N-二甲基甲酰胺中的溶胀度要大于在非极性溶剂四氢萘、起始溶剂和循环溶剂中的溶胀度;随着温度的升高,胜利煤的溶胀速率增大。溶胀后的胜利煤呈松散的云状结构,煤的形貌发生了一定程度变化;溶胀煤的孔径增大,比表面积减小。     

乳液聚合法制备聚苯胺及其导电性能

以十二烷基苯磺酸(DBSA)为乳化剂,十六醇(CA)为助乳化剂,盐酸和十二烷基苯磺酸（DBSA）为掺杂剂, 过硫酸铵为引发剂,采用乳液聚合法合成了导电聚苯胺（PAn）.研究了反应温度、反应时间及苯胺、十二烷基磺酸、十六醇、盐酸和过硫酸铵配比对聚苯胺电导率的影响.研究结果表明,较佳的工艺条件为：反应温度为7 ℃,反应时间为6 h,较佳的原料物质的量的比为苯胺∶十二烷基苯磺酸∶十六醇∶盐酸∶ 过硫酸铵=0.05∶0.028∶0.04∶0.01∶0.05;以十六醇为助乳化剂,采用十二烷基苯磺酸和盐酸为掺杂剂,提高了聚苯胺的导电性.同时对聚苯胺导电机理进行了分析.     

Preparation and corrosion resistance of nanostructured PVC/ZnO–polyaniline hybrid coating

ZnO–polyaniline nanocomposite with core–shell nanostructure was prepared by in situ polymerization of aniline monomer in the presence of ZnO nanoparticles. Fourier transform infrared spectroscopy, X-ray diffraction patterns, field emission scanning electron microscopy and transmission electron microscopy techniques were used to characterize the composition and structure of ZnO–polyaniline nanocomposite. d.c. electrical conductivity measurement showed that the electrical conductivity of ZnO–polyaniline nanocomposite pellets is higher than that of pristine polyaniline and ZnO nanoparticles pellets. The addition of ZnO nanoparticles causes to the increasing of polyaniline electrical conductivity. ZnO–polyaniline nanocomposite was mixed with polyvinyl chloride (PVC) through a solution mixing method and the three components PVC/ZnO–polyaniline hybrid material was applied as coating on iron coupon by the solution casting method. Corrosion protection efficiency of PVC/ZnO–polyaniline hybrid coating on iron coupons was studied by open circuit potential and Tafel techniques in 3.5% NaCl solution as corrosive environment. According to the results, PVC/ZnO–polyaniline hybrid nanocomposite coating showed dramatically increased corrosion protection effect on iron samples compared to that of uncoated iron coupon and pure polyaniline anticorrosive coating. It was found that ZnO nanoparticles improve the barrier and electrochemical anticorrosive properties of polyaniline and the addition of polyvinyl chloride increases the barrier effect of polyaniline coating.     

Biodegradable polyaniline/dextrin conductive nanocomposites: synthesis,characterization, and study of antioxidant activity and sorption of heavy metal ions

Conductive nanocomposites based on polyaniline/dextrin were synthesized by in situ polymerization of aniline in presence of dextrin. The nanocomposites were characterized by field emission scanning electron microcopy, differential scanning calorimetry, Fourier transform infrared spectroscopy, ultraviolet–visible spectroscopy, X-ray diffraction and conductivity measurements. It was observed that the conductivity values increased with the increase of aniline content in nanocomposites. The obtained nanocomposites have been analyzed for the antioxidant activities using 2,2-diphenyl-1-picrylhydrazyl assay. The results showed that the antioxidant activity of the nanocomposites was enhanced by increasing the aniline content. Polyaniline/dextrin nanocomposites were used as sorbent materials for the removal of heavy metals from aqueous solutions. The sorption data indicated that the novel polyaniline/dextrin nanocomposites have high tendency for the removal of heavy metal ions such as Cu(II), Cd(II) and Pb(II) from aqueous solutions. In addition, the in vitro biodegradability of polyaniline/dextrin nanocomposites with different weight ratios was studied by soil burial tests. The result demonstrated that the nanocomposites are biodegradable under soil environment by degradation range between 30.18 and 74.52 %. The observed physical properties of the polyaniline/dextrin nanocomposites open interesting possibilities for novel applications of electrically conducting polysaccharide-based composites, particularly those that may exploit the antioxidant activity and heavy metal ions sorption of the polyaniline/dextrin nanocomposites.     

聚苯胺及其复合材料研究现状

对聚苯胺的结构、合成及其机理、质子酸掺杂 ,聚苯胺的应用 ,以及聚苯胺复合材料的研究现状进行了综合阐述 ,并详细介绍了有关煤基聚苯胺的研究情况。煤基聚苯胺和纯聚苯胺相比 ,电导率下降不大 ,而且成本降低、热稳定性增强 ;同时 ,煤基聚苯胺也为煤的非能源利用提供了新途径和新机遇 ,具有一定的推广价值。