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1.
In this paper, we report the synthesis of poly(N-ethylaniline) (PNETA) by using tartaric acid (TA) as an organic acid dopant by aqueous polymerization method of N-ethylaniline using ammonium per sulphate (APS) as an oxidant and acrylic acid (AA) as a soft template. This is a new polymerization method for the direct synthesis of the emeraldine salt form of poly(N-ethylaniline) in bulk quantity, which is soluble in organic solvents such as m-cresol and N-methyl pyrrolidinone. The prepared polymers were characterized by UV, FTIR, XRD, TGA, SEM and conductivity measurement studies. The results are discussed with reference to HCl doped poly(N-ethylaniline). It is observed that PNETA/TA/AA polymer is comparatively more soluble in m-cresol than that doped with HCl in its salt form. The formation of emeraldine salt phase and dopping process was confirmed by FTIR and UV-Vis spectroscropy. We demonstrate the effect of organic dopant on the morphology and conductivity of the PNETA. It was found that, PNETA doped with TA synthesized using acrylic acid (AA) as a soft template display higher doping level, crystallinity and solubility in common organic solvent. On the contrary, HCl doped polymer was lowered at doping level and amorphous in nature which reflects the role of organic dopant and soft template. X-ray diffraction studies indicate that the PNETA/TA/AA doped samples exhibit higher crystallinity, which indicates enhanced polymer sub-chain alignment as compared to HCl doped polymer. This is also manifested by the FTIR studies. SEM result also revealed the continuous morphology and sub-micrometer size, evenly distributed particles of the PNETA/TA/AA doped polymer.  相似文献   

2.
在用琥珀酸二异辛酯磺酸钠(AOT)构建的具有长程有序结构的层状溶致液晶内, 用不同方式导入预制的亲油或亲水贵金属纳米粒子, 可得到纳米粒子分布在不同介观空间内的无机/有机杂合体. 依据小角X射线散射和偏光显微镜结果, 通过分析掺杂纳米粒子与液晶模板的相互作用, 对掺杂前后体系结构的变化及制得杂合体的稳定性进行了表征. 结果表明, 除考虑掺杂粒子与层状模板空间的匹配外, 体系中静电斥力、范德华引力和Helfrich涨落力之间的平衡是维持液晶结构稳定的基本条件.  相似文献   

3.
靖波  陈晓  隋震鸣  王庐岩  柴永存  邱化玉 《化学学报》2006,64(13):1319-1323
选择非离子表面活性剂十二烷基(4)聚氧乙烯醚(C12E4)与H2O构成的溶致液晶(LLC)层状模板, 掺杂油酸铵包覆的Fe3O4亲水性磁性纳米粒子, 构建稳定的有机/无机杂合体. 用透射电镜(TEM), X射线粉末衍射(XRD), 偏光显微镜(POM), 小角X射线散射(SAXS)和振动探针式磁强计(VSM)等对粒子及掺杂前后的层状液晶相结构变化进行表征. 结果表明, 粒子掺入使LLC模板的层间距产生了改变, 同时增强了体系有序性.通过对杂合体表征结果的分析, 阐述了模板与粒子间相互作用的机理.  相似文献   

4.
Sol-gel copolymerization of iron tricarbonyl-2-(triisopropoxysilyl)-1,3-butadiene with 1,6-bistriethoxysilylhexane and 1,4-bistriethoxysilylbenzene followed by drying produced bridged polysilsesquioxane xerogels. These porous, transparent hybrid materials containing the iron metal precursor were irradiated (UV) and heated under vacuum resulting in the deposition of nano-sized iron particles doped in the xerogels. EDAX and electron diffraction techniques were used to characterize the iron phases. The TEM images of these doped xerogels provided additional information regarding the domain size of the iron phase.Using a combination of external doping of Cd2+ and S2– ions and internal doping of Fe°, mixed Fe/CdS phases were prepared within the porous bridged polysilsesquioxane xerogels. The resulting doped xerogels were found to have retained their porous morphology.  相似文献   

5.
The enzyme horseradish peroxidase (HRP) was used to polymerize acid‐functionalized anilines to make self‐doped polymer in the presence of a polycationic template. Anionic templates such as sulfonated polystyrene (SPS) could not function as a suitable template for the polymerization of acid‐functionalized aniline derivatives. Several types of polyelectrolytes were used as templates to observe the structural effects and doping behavior of polyaniline/template complexes. The synthesis is straightforward and the conditions are mild in that the polymerization of conducting polyanilines may be carried out in buffered solutions as high as pH 6, with a stoichiometric amount of hydrogen peroxide and catalytic amount of enzyme. The conductivity of these enzymatically synthesized self‐doped polymers was relatively high without additional doping due to the self‐doping of the acid moieties. The conductivity did not decrease dramatically at pH 3 as is the usual case of unsubstituted HCl‐doped polyaniline and maintained good conductivity even at pH 6. The measured conductivity at pH 4~pH 6 is around 10?4 S/cm to 10?6 S/cm.  相似文献   

6.
Pickering乳滴模板法制备有机/无机杂化的核壳微球越来越引起人们的关注,主要因为该方法制备出的微球具有以无机粒子为壳层的超粒子结构(supracolloidal structure),能够赋予微球独特的功能.胶体粒子在乳滴表面自组装形成有序的球面胶体壳,得到稳定Pickering乳液,固定乳滴表面的胶体粒子来制备核壳结构的微球或者以胶体粒子为壳层的微胶囊(colloidosome).本文综述了我们课题组以Pickering乳滴模板法制备超粒子结构有机/无机杂化微胶囊包括实心微球方面的工作.我们选择具有不同性能、种类的胶体粒子以及具有不同性质和功能的核材料,采用Pickering乳滴模板法,对吸附在乳滴表面的胶体粒子用不同的固定方法制备具有不同结构和性能的微球和微胶囊,利用基于多重Pickering乳液的聚合技术制备双纳米复合的超粒子结构多核聚合物微球.  相似文献   

7.
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.  相似文献   

8.
Polystyrene nanoparticles doped with a luminescent europium complex, Eu(tta)(3)phen, are prepared by miniemulsion polymerization. The influence of the complex on the miniemulsion polymerization is investigated by the systematic variation of the initial concentration of Eu(tta)(3)phen from 2 to 7 wt% relatively to styrene. A maximum doping level of about 2% by weight in the final particles can be achieved. At higher doping levels, destabilization of the miniemulsion leads to a loss of reproducibility with respect to both the degree of conversion and the final Eu content of the particles. Doped nanoparticles of varying diameter, ranging from 19 to 94 nm, are successfully prepared. Steady-state and time-resolved luminescence measurements indicate that the luminescence properties of Eu(tta)(3)phen in the doped latexes are unchanged from those found in THF solution. Aqueous dispersions of the doped particles exhibit characteristic red emission under UV light irradiation. The luminescence intensity increases linearly with Eu(tta)(3)phen content, indicating the absence of self-quenching despite the relatively high local concentrations within the particles.  相似文献   

9.
4-hydroxy-4 ‘-nitro azobenzene (NHA) and 4-amino-4 ‘-nitro azobenzene (DO3) were prepared respectively from p-nitrophenylamine as a precursor compound. Two kinds of doped organic/inorganic hybrid nonlinear optical (NLO) materials containing NHA and DO3 were synthesized by Sol-Gel process. The preparation and properties of two NLO materials were studied and characterized by FTIR, IH-NMR, UV-VIS, SEM, DSC and SHG measurements. The results show that the maximum doping amounts of NHA and DO3 in two doped hybrid NLO materials are 7.2(wt)% and ll.3(wt)% respectively, and the corresponding second-order NLO coefficients (d33values) are 2.91 ×l0^-3esu and 6.14×10 -8 esu. Two doped NLO materials have relatively good RT stability, after 90 days at RT the d33 values can maintain about 85% of their initial values, but after l0h at 100℃ can only maintain about 50% of their initial values. In this report, the reasons for high-temperature instability of doped materials were discussed, and the possible improvements were also suggested.  相似文献   

10.
We present a study of the electrical properties of electrochemically doped conjugated polymers using polymeric light-emitting electrochemical cells (PLECs) and interpreting the results according to a phenomenological model (PM) which assumes that, above the device turn-on voltage, the bulk transport properties of the doped organic semiconductor are responsible for the main contribution to the whole device conductivity. To confirm the predictions of this model, the dependence of the conductivity of PLECs with different parameters is evaluated and compared with the behavior expected for a doped semiconducting polymeric material. The organic semiconductor doping level, the blend concentration of organic semiconducting molecules, the device thickness, the charge carrier mobility, and the temperature are the parameters varied to perform this analysis. We observed that the device conductivity is independent of the active layer thickness, weakly dependent on the temperature, but strongly dependent on the semiconductor doping level, on the semiconductor fraction in the blend, and on the intrinsic charge carrier mobility. These results were well described by the variable range hopping (VRH) model, which has been widely employed to describe the charge transport in doped semiconducting polymeric materials, confirming the prediction of the phenomenological model. The current analysis demonstrates that PLECs are a suitable system for studying, in situ, the electrochemical doping of semiconducting polymers, permitting the evaluation of material properties as, for instance, the density of electronic charge carriers (and, consequently, the ionic charge carrier concentration) necessary to achieve the maximum electrochemical doping level of the organic semiconductor.  相似文献   

11.
Catalytic natures of organometallic catalysts are modulated by coordinating organic ligands with proper steric and electronic properties to metal centers. Carbon‐based nanomaterials such as graphene nanoplatelets are used with and without N‐doping and multiwalled carbon nanotube as a ligand for ethylene polymerizations. Zirconocenes or titanocenes are immobilized on such nanomaterials. Polyethylenes (PEs) produced by such hybrids show a great increase in molecular weight relative to those produced by free catalysts. Specially, ultra‐high‐molecular‐weight PEs are produced from the polymerizations at low temperature using the hybrid with N‐doped graphene nanoplatelets. This result shows that such nanomaterials act a crucial role to tune the catalytic natures of metallocenes.  相似文献   

12.
有机/高分子共轭聚合物的结构设计是制备高性能有机半导体的有效策略,但该过程存在着设计合成周期长、制备步骤复杂和产率偏低等问题。为了克服这些问题,近年来人们越来越关注对有机/高分子半导体的掺杂。然而,传统电荷转移掺杂剂(如卤族单质I2、金属氧化物Fe3O4、小分子F4TCNQ等)存在掺杂效率低、溶解度差和掺杂条件苛刻等问题。相比之下,三(五氟苯基)硼烷具有溶解度高、掺杂效率高、广泛适应性等优点。本文结合相关文献综述了三(五氟苯基)硼烷掺杂有机半导体的物理机制,并探讨了掺杂有机半导体的性质;此外,还总结了三(五氟苯基)硼烷掺杂在不同光电功能器件中的应用并明确了今后的研究方向。  相似文献   

13.
Inorganic–organic hybrid coatings by sol–gel process are very suitable for fighting corrosion. Inorganic sols in hybrid coatings not only increase adhesion by forming chemical bonds between metals and hybrid coatings, but also improve comprehensive performances of polymer in the coatings. Different organic polymers or organic functionalities are introduced into gel network to achieve tailored properties, such as hydrophobic properties, increasing cross-linking density, etc. As for corrosion protection of metals organic components of hybrid coatings are selected to repel water and form dense thick films and reduce coating porosity. The factors, such as the ratio of inorganic and organic components, cure temperature, pigments in hybrid coatings, need to be optimized for attaining hybrid films with the maximum corrosion resistance. Electro-deposition technique offers relatively thick homogeneous defect-free hybrid coatings in comparison to dip or spin coating techniques. Green cerium ions and non-ionizable organic inhibitors are more developed in hybrid coatings nowadays than other corrosion inhibitors. Long-term corrosion resistance techniques of inhibitors are discussed. The inhibitors entrapped in the nanocontainers are doped in hybrid films to prolong release of the inhibitors to damaged zones, which is discussed in detail. Among all the nanocontainers of corrosion inhibitors the prospective techniques which show superior corrosion protection are cyclodextrin/organic inhibitor inclusion complexes and layer by layer assembly of organic corrosion inhibitors in nanocontainers. Super-hydrophobic property of hybrid coatings derives from low surface tension and surface roughness of hybrid coatings, which endues the films with excellent corrosion protection for metals, but the durable property of super-hydrophobic coatings needs to be improved for industrial application. An ideal multiple model of hybrid coatings for superior anti-corrosion of metals proposed is a combination of super-hydrophobic hybrid coatings and underlying hybrid coatings doped with sustained release of corrosion inhibitors on metal substrates.  相似文献   

14.
Mn‐doped SrMoO4 nanocrystals were synthesized by thermal decomposition of metal–organic salt in an organic solvent with the doping content in the range 0–12 mol%. The structures, morphologies and optical properties were characterized using various techniques. The results suggest that Mo sites in the SrMoO4 lattice are substituted by the Mn dopant, the adsorption bands are found to be shifted toward the visible light region and the band gap becomes narrower correspondingly. The photocatalytic performance of the as‐synthesized product was determined using the degradation of methylene blue by visible light irradiation. The photocatalytic performance is enhanced with Mn doping, and the optimal degradation rate is 85% in 140 min for 5 mol% Mn doping. The enhanced photocatalytic activity with Mn doping may be ascribed to the energy band adjustment and effective photogenerated electron–hole separation caused by the Mn doping. A possible photocatalytic mechanism is also discussed.  相似文献   

15.
本文采用溶胶-凝胶法制备了以活性炭纤维(ACF)为模板的掺氮TiO2光催化剂,利用XRD、XPS、TEM、SEM和UV-Vis等方法对催化剂进行了表征,测定了催化剂在紫外、日光照射下光催化脱氨氮的活性.ACF作模板掺氮TiO2催化剂具有介孔结构,平均粒径约为10 nm,比表面积为64.43 m2/g.紫外、可见光光催化2 h氨氮(85 mg/L)废水的氨氮去除率分别为68%和47%.结果表明,催化剂中氮的含量是影响催化剂光催化活性的重要因素.  相似文献   

16.
对聚苯胺在有机溶剂中掺杂质子酸的反应进行了in-situ UV-Vis光谱跟踪,用因子分析法对掺杂反应机理进行了研究.结果表明,聚苯胺在有机溶剂中掺杂质子酸的过程可能存在着两个并行反应:一个是掺杂与脱掺杂的动态平衡过程,在实验条件下反应的平衡常数约为k=5.16(24℃);另一个反应为副反应,生成的产物结构介于本征态与平衡掺杂态之间,很可能是反应过程中形成的包含不同掺杂形态的混合体.  相似文献   

17.
田明 《高分子学报》2001,18(5):639-644
提出了以具有纳米尺寸孔径及孔壁厚度的MCM 48作为无机基体、以无机 有机原位自组装的方法形成纳米网络粒子 .研究结果表明 ,在一定实验条件下 ,有机相可进入无机相的三维孔道自组装形成立方有序结构的纳米网络复合粒子 .通过研究纳米网络粒子在极性介质和非极性介质中的分散发现 ,有机相的存在有利于纳米网络粒子的分散  相似文献   

18.
Antibacterial activity was imparted with polyamidoamine (PAMAM) side chain dendritic polyurethane (SCDPU‐PEG) by doping of silver particles. Antibacterial activities of both the polyurethane (SCDPU‐PEG) and its silver doped structures were investigated against Escherichia coli bacteria. The silver doped polymeric structures were found to exhibit antibacterial activity while the polymer without silver loading showed no antibacterial activity. Formation of silver doped side chain dendritic polymers was investigated from the UV‐vis plasmon absorption band of silver particles.  相似文献   

19.
Using polystyrene(PSt) particles as template,PSt/TiO2 composite particles with AgCl incorporation were prepared through hydrolysis of tetrabutyl titanate in the presence of AgNO3 and NaCl.AgCl doped TiO2 hollow particles were successfully prepared with the PSt/TiO2 composite microspheres pretreated at 180℃followed by calcination.The morphology of PSt/TiO2 particles and the crystal structures of the AgCl doped TiO2 hollow particles were characterized.The photocatalytic activity of the doped TiO2 hollow particles in degradation of Rhodamine B was tested under UV and visible lights and compared to that with Ag doped TiO2 particles.The results showed that TiO2 hollow particles,either doped with Ag or AgCl,demonstrated higher photocatalytic activity than the pure TiO2 particles.This enhancement in photocatalytic activity was more significant with AgCl doped TiO2 than that with Ag doped,and more distinct when the degradation was done under visible light than that under LTV light.  相似文献   

20.
溶胶-凝胶法制备光学杂化功能材料   总被引:9,自引:0,他引:9  
刘冰  强亮生 《化学进展》2005,17(1):0-90
在简述溶胶-凝胶法基本原理的基础上,介绍了设计杂化材料的原则及预掺杂法、后掺杂法和原位化学合成法三种溶胶-凝胶法制备光学杂化功能材料的途径;综述了稀土发光材料、波导材料和光致变色材料三种光学杂化功能材料,并结合国内外的研究提出开展光学杂化功能材料研究的重要方向.  相似文献   

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