苯胺电化学聚合机理的研究

主要应用电化学方法研究了苯胺及其电化学聚合产物─—聚苯胺的循环伏安曲线，同时讨论了苯胺的存在对４－氨基二苯胺循环伏安曲线的影响。结果表明：随着苯胺聚合的进行，聚苯胺同时发生降解；苯胺电化学聚合按“白催化机理”进行。     

Dispersion Oxidative Polymerization of Pyrrole in Aqueous Solutions of Polyvinyl Alcohol

Russian Journal of General Chemistry - Kinetics of the oxidative polymerization of pyrrole in an aqueous solution of poly(vinyl alcohol) under the action of ammonium peroxydisulfate has been...     

Sequential Electrochemical Polymerization of Aniline and Their Derivatives Showing Electrochemical Activity at Neutral pH

Sequential electropolymerization of aniline followed by an aniline derivative bearing an ion moiety is presented. The studied derivatives contain sulfonic, carboxylate or amino groups. Its electrochemical behavior at acid and neutral pH is studied by cyclic voltammetry combined with quartz crystal microbalance or probe beam deflection in order to assess the mass transfer process involved in these new modified electrodes. All of them show a stable and quasi‐reversible electrochemical behavior at neutral pH that can be attributed to a self‐doping process. These new modified electrodes can be further modified due to the presence of functional groups.     

低温悬浮聚合法合成超高聚合度的聚乙烯醇

以偶氮二异庚腈(ADMVN)为引发剂,通过悬浮聚合法合成聚醋酸乙烯(PVAc),PVAc经醇解制备超高聚合度(Pn)的聚乙烯醇(PVA)。实验结果显示较适宜的反应条件为:VAc 80 g,V(H2O)∶V(VAc)=1∶1,cADMVN=0.1%(以VAc质量计),悬浮剂浓度(cPVA-2288)=1.5%(以水质量计),搅拌速度(r)300 rmp,于30℃反应24 h,单体VAc的转化率超过90%,PnPVA为4.0×103~6.6×103。cPVA-2288和r是影响PVAc颗粒直径(DPVAc)及其分布的主要因素:DPVAc∝[cPVA-2288]-1.45,DPVAc∝r-1.79。     

影响苯胺电化学计量聚合因素的探讨

本文对影响苯胺电化学计量聚合的因素进行了探讨，这些因素包括：电化学聚合方法、电极电位（Ｅ）、电流密度（Ｉ），以及苯胺单体和酸溶液的浓度等，实验结果表明，最合适的聚合方法为恒电流法，其条件为：电极电位不大于０．７０Ｖ（ｖｓ．ＳＣＥ）聚合电流密度（Ｉ）约为０．０５ｍＡ／ｃｍ＾２，苯胺单体浓度为１．１ｍｏｌ／Ｌ，酸（ＨＣｌ）的浓度则为２．２ｍｏｌ／Ｌ     

超微盘电极上苯胺的循环扫描伏安法电化学聚合

本文对超微盘电极上苯胺的循环扫描伏安法电化学聚合进行了研究。对研究过程的伏安曲线性质以及峰电流和单体浓度，循环扫描次数和速率及电位之间的关系作了详细的探讨，还给出了峰电流的经验式。     

Electrochemical Polymerization of Aniline at Low Supporting-Electrolyte Concentrations and Characterization of Obtained Films

Conductive polymers of aniline were synthesized in aqueous acidic media such as perchloric, sulfuric, hydrochloric, phosphoric, and trifluoroacetic acids and the effect of supporting electrolyte was investigated. The conductivity of each polyaniline (PAn) sample was determined by the four-probe technique. PAn (H₂SO₄) sample was shown to have the highest conductivity, specifically, 3.55 S cm^–1. The effect of concentrations of monomers and acids on the conductivity of PAn's was studied. It was observed that the conductivity decreased with increasing aniline concentration and increased with increasing sulfuric acid concentration. The conductivities of PAn (CF₃COOH) were also investigated in different supporting electrolytes and highly good increments of its conductivities were obtained. Magnetic properties of the PAn salts were analyzed by Gouy balance measurements and it was found that their conducting mechanisms are of bipolaron nature. From the FTIR analysis it was found that polymerization occurs via the –NH₂ group in a head-to-tail mechanism. The thermal analyses revealed that PAn (HCl) among the PAn salts studied shows the highest thermal stability. Surface analyses of polymers were clarified by scanning electron microscopy. From elemental analysis results, PAn salts were concluded to be in emeraldine structure.     

超微电极上恒电位法苯胺的电化学聚合研究

本文对超微盘电极上苯胺的恒电位电化学聚合进行了研究，对聚合电流随时间的关系进行了详细的讨论，提出了径向聚合计时电流方程式并进行了验证，实验结果与理论相符。     

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。     

Acetalization of Polyvinyl Alcohol Fiber with Aldehyde-containing Polyvinyl Alcohol Fiber

A procedure is proposed for preparing polyvinyl alcohol fiber with increased water absorption by acetalization of a freshly formed fiber with dialdehyde-containing polyvinyl alcohol fiber. The fiber characteristics were determined in relation to the acetalization conditions.     

苯胺自催化聚合反应的混合电位

在苯胺自催化聚合反应的开路电位实验中,Pt、Pd和聚苯胺膜具有远正于其它金属的开路电位.该实验结果可以根据混合电位理论来解释.由于苯胺自催化聚合反应具有电化学机理,因此该反应的基底材料将具有同时对应于阳极半反应和阴极半反应的混合电极电位.混合电位在实验上表现为开路电位,其数值大小可以看作是苯胺自催化聚合反应能否进行的标志.有关开路电位的实验结果进一步证明了苯胺自催化聚合反应的电化学机理.     

The Electrochemical Properties of Nanocomposite Films Obtained by Chemical In Situ Polymerization of Aniline and Carbon Nanostructures

Interactions between the π bonds in the aromatic rings of polyaniline (PANI) with carbon nanostructures (CNs) facilitate charge transfer between the two components. Different types of phenyleneamine‐terminated CNs, including carbon nano‐onions (CNOs) and single‐walled and multi‐walled carbon nanotubes (SWNTs and MWNTs, respectively), were prepared as templates, and the CN/PANI nanocomposites were easily prepared with uniform core–shell structures. By varying the ratio of the aniline monomers relative to the CNs in the in situ chemical polymerization process, the thickness of the PANI layers was effectively controlled. The morphological and electrical properties of the nanocomposite were determined and compared. The thickness and structure of the PANI films on the CNs were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and infrared spectroscopy. TEM and SEM revealed that the composite films consisted of nanoporous networks of CNs coated with polymeric aniline. The electrochemical properties of the composites were investigated by cyclic voltammetry and electrochemical impedance spectroscopy. These studies showed that the CN/PANI composite films had lower resistance than pure polymeric films of PANI, and the presence of CNs much improved the mechanical stability. The specific electrochemical capacitance of the CNO/PANI composite films was significantly larger than for pure PANI.     

氰基乙烯基苯胺衍生物的电化学行为

本文利用循环伏安法研究了电子给-受体模型化合物——氰基乙烯基苯胺衍生物的电化学行为,并对推电子取代基团—NH_2和—N(CH_3)_2与吸电子取代基团氰基乙烯基对化合物电化学行为的影响进行了较为详细的讨论.提出了这些化合物的电氧化态和电还原态的结构,通过分析比较叔、仲和伯自由基对化合物电化学行为的影响,探讨了电极反应机理.     

聚乙烯醇缩对甲酰基偶氮氯膦的合成及其性质

首次报道了聚乙烯醇缩对甲酰基偶氮氯膦（简称：ＰＶ·ＣＰｐＦ）的合成、纯化及其鉴定方法,并初步探讨了在光度分析和非有机溶剂萃取分离方面的应用。结果表明,小分子显色剂高分子化后,其分析性能有了明显改善,特别是显色灵敏度和萃取率均有不同程度的提高。     

石英晶体微天平上的苯胺自催化聚合反应

聚苯胺;石英晶体微天平上的苯胺自催化聚合反应     

苯胺分散聚合中稳定剂PVP-K90的稳定机理

通过分散聚合,在聚酰亚胺(PI)薄膜表面原位沉积聚苯胺(PANI)制备聚苯胺-聚酰亚胺-聚苯胺(PANI-PI-PANI)复合膜。考察了苯胺分散聚合中,不同空间稳定剂的稳定效果(不同分子量的大分子稳定剂PVP及小分子稳定剂CTAB、Tween-20),初步探讨了大分子稳定剂PVP-K90的稳定机理。实验表明,高分子量PVP-K90可稳定PANI良好成膜,且紫外和红外光谱分析证实PANI膜为掺杂态PANI,膜中不含有稳定剂PVP-K90。低分子量的PVP-K30和两亲性小分子稳定剂不能良好地稳定PANI成膜,稳定作用较差。PVP-K90的稳定作用不仅依据亲水-疏水相互作用和表面能的减少,还可能与高分子量PVP的长链分子结构及与水和苯胺的特殊相互作用有关,可用齐聚物沉淀成核机理解释。     

苯胺在十二烷基苯磺酸/水体系中的乳液聚合过程研究

利用光学显微镜和扫描电镜,对以水为介质、十二烷基苯磺酸(DBSA)为乳化剂的苯胺乳液聚合过程进行监测,发现苯胺在水体系中与DBSA反应形成DBSA-苯胺盐的棒状聚集结构,讨论了DBSA、苯胺、氧化剂的配比及浓度对聚合过程中棒状聚集结构的长度和数量及生成聚苯胺的电导率的影响,提出苯胺在DBSA/水体系中的乳液聚合反应是在胶束表面进行的,而棒状聚集结构中的DBSA-苯胺盐单体经水相扩散到乳胶粒子中,形成颗粒状的聚苯胺.     

Oxidation and Destruction of Polyvinyl Alcohol in the Aqueous Phase

We have studied kinetic laws of polyvinyl alcohol oxidation under the action of an ozone–oxygen mixture and hydrogen peroxide in an aqueous medium. It is shown that polymer oxidation is carried out by the radical mechanism. The scheme of oxidative transformations of polyvinyl alcohol explaining the obtained results is suggested.