单分散P(St-BA-AN)/PANI核壳结构复合微球的制备与电性能

以苯乙烯(St)、丙烯酸丁酯(BA)和丙烯腈(AN)为单体, 采用乳液聚合的方法制备出单分散苯乙烯-丙烯酸丁酯-丙烯腈三元共聚物[P(St-BA-AN)]种子微球, 再在该种子微球表面包覆聚苯胺(PANI), 制得P(St-BA-AN)/PANI核壳结构复合微球. 采用扫描电镜(SEM)、透射电镜(TEM)、傅里叶变换红外透射光谱(FTIR)和漫反射光谱等测试手段对所制备的种子微球和复合微球的形态、结构和形成机理进行了研究, 并用四探针法测定了核壳结构复合物的导电性. 研究结果表明, 通过改变种子乳液共聚物的组成和加入苯胺的量及氧化剂的量等条件可调控复合微球的电导率. 与P(St-BA)/PANI核壳结构复合微球相比, 在核组成中引入了氰基的P(St-BA-AN)/PANI核壳结构复合微球的电导率明显提高, 当加入苯胺的量为P(St-BA-AN)种子微球与苯胺单体总质量分数的40%时, 其电导率可达到0.71 S/cm. 红外光谱结果证实了P(St-BA-AN)种子微球中的氰基和壳层中聚苯胺的胺基之间存在某种相互作用, 导致核壳结构复合物电导率的提高.     

手性聚苯胺/二氧化硅核/壳复合物的合成及应用

以苯胺为单体,右旋樟脑磺酸为手性掺杂剂制备了手性聚苯胺[(+)-PANI];以(+)-PANI为核,表面包覆二氧化硅外壳,得到手性聚苯胺/二氧化硅核/壳复合物[(+)-PANI@SiO_2].采用比旋度([α]t D)、紫外-可见光谱(UV-Vis)及圆二色谱(CD)等表征光学活性,结果表明,(+)-PANI及(+)-PANI@SiO_2均具有手性;红外光谱(IR)表明,二氧化硅已经包覆于(+)-PANI表面;扫描电子显微镜(SEM)结果表明,(+)-PANI@SiO_2为核/壳结构.将(+)-PANI和(+)-PANI@SiO_2分别用于丙氨酸对映体选择性结晶,L-丙氨酸均优先结晶,且(+)-PANI@SiO_2手性识别能力更强.以光学活性聚苯胺为核,无机二氧化硅为壳的核/壳复合物在手性识别领域具有潜在的应用价值.     

壳层可控导电聚吡咯/聚苯乙烯复合微球及聚吡咯中空微胶囊的制备

在导电聚合物含量较小时,含核壳结构的导电聚合物复合粒子就可以具有和本体相当的导电率,且加工性好,近年来这种核壳结构微粒的制备已引起了科学家们的广泛关注．Armes等[制备了导电聚吡咯、导电聚苯胺包覆聚苯乙烯的核壳结构胶体粒子及聚苯胺和二氧化硅的纳米复合物．刘正平等用改进的方法在粒径为116nm的单分散聚苯乙烯乳胶粒子上包覆聚吡咯,     

二次掺杂对聚苯胺导电复合物性能的影响

研究了聚苯胺与（苯乙烯－丁二烯）三嵌段共聚物或氯碘化聚乙烯复合物在间甲酚二次掺杂前后电导率的变化（提高２个数量级），根据二次掺杂使聚苯胺复合物增强永久形变和断面形貌脆断一次掺杂使卷曲的聚苯胺链展开并通过这间的弱相互作用而自行组成导电能通路，复合物二次掺杂前后的抗张强度和伸长率变化不大，说明其主链间的弱相互作用对应力无贡献，此外，还研究了二次掺杂对复合物在中性和酸必南中电致变色活性的影响。     

两亲性纤维素接枝聚脱氢枞酸共聚物的制备及性能研究

通过均相原子转移自由基聚合法(ATRP)将生物质基疏水性松香单体(脱氢枞酸(2-甲基丙烯酰氧基乙基)酯,MAEDA)接枝到纤维素骨架上合成了全生物质基两亲性的纤维素-g-聚脱氢枞酸接枝共聚物(cellulose-g-PMAEDA).ATRP反应过程动力学研究表明cellulose-g-PMAEDA接枝共聚物的合成过程是活性可控的;傅里叶红外光谱(FTIR)、核磁共振氢谱(1H-NMR)、凝胶色谱(GPC)和X射线衍射(XRD)结果证实了cellulose-g-PMAEDA接枝共聚物的成功合成;由于聚脱氢枞酸侧链的引入,cellulose-g-PMAEDA接枝共聚物的热稳定性,疏水性能明显提高,并且具有紫外吸收性能;动态光散射仪和透射电镜结果表明两亲性cellulose-g-PMAEDA接枝共聚物能够在水溶液中自组装成平均粒径约为200 nm左右的纳米微球,并且该纳米微球具有以纤维素为壳,聚脱氢枞酸酯为核的核壳结构.     

聚苯胺/镧取代锂镍铁氧体纳米复合物的制备、表征及磁性

在盐酸溶液中通过原位聚合法制备了磁性聚苯胺/镧取代锂镍铁氧体（LiNi_0.5La_0.02Fe_1.98O₄）纳米复合物。在外加磁场下纳米复合物表现出了磁滞现象，其饱和磁化强度（Ms）和矫顽力（Hc）随铁氧体含量的改变而变化。用X-射线衍射（XRD）、透射电子显微镜（TEM）、扫描电子显微镜（SEM）、红外光谱（FT-IR）、紫外-可见光谱（UV-Vis）以及振动样品磁强计（VSM）等对纳米复合物进行了表征。TEM和SEM表明纳米复合物具有核-壳结构。XRD、FT-IR和UV-Vis光谱揭示了纳米复合物中铁氧体与聚苯胺之间存在着一定的键合作用，并探讨了铁氧体与聚苯胺之间的键合机制。     

绝缘聚合物对聚苯胺复合物导电性能的影响

将十二烷基苯磺酸掺杂的聚苯胺(PAn DBSA)与乙烯丙烯酸共聚物(EAA)或聚烯烃弹性体(POE)进行溶液共混制得了PAn DBSA/EAA或PAn DBSA/POE导电复合物。研究了绝缘聚合物的化学结构对聚苯胺导电复合物形态结构及电性能影响。结果表明,极性聚合物EAA中的羧基能与PAn形成氢键并发生掺杂作用,复合物中卷曲的PAn主链能充分展开,导致PAn/EAA复合物具有非常低的逾渗域值(1.5%),PAn含量为20.0%时,电导率高达7.1S/cm。POE为非极性共聚物,与极性较强的PAn相容性较差,导致PAn/POE复合物具有较高逾渗域值(5.0%),PAn含量为20.0%时,电导率仅为3.0×10-5S/cm。     

基于PAA-b-PAN嵌段共聚物胶束制备磁性碳纳米粒子

本文采用原子转移自由基聚合方法合成了聚丙烯酸叔丁酯-聚丙烯腈嵌段共聚物(PtBA-b-PAN),酸解得到聚丙烯酸-聚丙烯腈两亲嵌段共聚物(PAA-b-PAN).随后,PAA-b-PAN嵌段共聚物在水溶液中自组装形成以PAA为壳,PAN为核的胶束.用此胶束为模板,加入FeCl3溶液后得到了壳层负载Fe3+的聚合物纳米粒子,经230℃空气中预氧化,600℃氮气氛煅烧,得到了核壳结构的,具有磁性的碳纳米粒子.用1HNMR,IR,GPC,TGA,TEM,XRD,AGM等技术对嵌段共聚物及纳米粒子进行了表征,结果表明纳米粒子的壳层含γ-Fe2O3,Fe2.5C混合物,核含碳,直径为35±5nm,饱和磁化强度为2.16emu/g.在分离、吸波和传感器等方面具有潜在的应用前景.     

壳聚糖作用下一步法合成具有高电活性的AgCl@聚苯胺核壳结构

在壳聚糖的作用下，采用简单的一步法合成了具有星状结构的氯化银/聚苯胺核壳型复合材料。当壳聚糖的浓度为1%时，所制备的氯化银/聚苯胺复合材料具有高度的分散性，壳层厚度为30～80 nm、核的直径在25～60 nm范围内。通过透射电镜、红外光谱和X-射线衍射对样品的形态和组成进行了表征。循环伏安实验结果表明这种复合材料在中性条件下具有很好的电化学活性。     

具有伸展链构象聚苯胺/蒙脱土混杂纳米复合物的合成与表征

报道了具有聚苯胺伸展链构象的聚苯胺／ 粘土（ Ｐ Ａｎ／ Ｍ Ｍ Ｔ） 混杂纳米复合物的合成与表征．用插层聚合的方法将聚苯胺分子链嵌入层状蒙脱土的片层之中,从而得到一种高电导率的聚苯胺／ 层状硅酸盐混杂纳米复合物．通过 Ｘ 射线衍射（ Ｘ Ｒ Ｄ） ,付立叶红外（ Ｆ Ｔ Ｉ Ｒ） ,四探针电导率测量以及定性和定量的电子光谱分析等手段对产物进行了表征,结果表明,９０ ％ 以上的聚苯胺的分子链被插入蒙脱土的片层中间．由于聚苯胺分子链在受限的纳米空间生成,聚苯胺以伸展的单分子链构象存在．该构象在苯胺的通常聚合中不可能生成．通过对聚合过程进行吸收光谱监测,发现该聚合是扩散控制过程．     

Spherical Polarization Body: Synthesis of Monodisperse Micron‐Sized Polyaniline Composite Particles

A new method to synthesize uniform polyaniline‐coated composite microparticles was contrived considering the surface reactivity and porous structure of substrate polymer particles. It was found that the pore diameter together with the epoxy functional group plays a crucial role in controlling the structure of polyaniline shell. The polyaniline composite particles produced in this study are believed to find great applicability in piezoelectronics and as electro‐rheological fluids.     

Synthesis and characterization of dual‐responsive micrometer‐sized core‐shell composite polymer particles

Dual‐responsive micrometer‐sized core‐shell composite polymer particles were prepared by dispersion polymerization followed by seeded copolymerization. Polystyrene (PS) particles prepared by dispersion polymerization were used as core particles. N‐isopropyl acrylamide (NIPAM) and methacrylic acid (MAA) were used to induce dual‐responsive that is thermo‐ and pH‐responsive properties in the shell layer of composite polymer particles, prepared by seeded copolymerization with PS core particles. Temperature‐ and pH‐dependent adsorption behaviors of some macromolecules on composite polymer particles indicate that produced composite polymer particles exhibit dual‐responsive surface properties. Copyright © 2007 John Wiley & Sons, Ltd.     

Preparation of heterogeneous film from core-shell composite polymer particles produced by the stepwise heterocoagulation method with heat treatment

Core-shell composite polymer particle consisting of a hydrophilic core and hydrophobic shell was produced by the stepwise heterocoagulation of small cationic styrene-butyl acrylate-methacryloyoxyethyl trimethylammonium chloride terpolymer particles onto a large anionic methyl methacrylate-ethyl acrylate-methacrylic acid terpolymer particle (LP), which was proposed by the authors in 1990. In order to prepare a film from such a core-shell composite polymer emulsion, the shell content was controlled by changing the diameter of LP and by increasing the methacrylic acid content in LP.     

Preparation and clinical application of immunomagnetic latex

Magnetic poly(methyl methacrylate) (PMMA)/poly(methyl methacrylate‐co‐methacrylic acid) [P(MMA–MAA)] composite polymer latices were synthesized by two‐stage soapless emulsion polymerization in the presence of magnetite (Fe₃O₄) ferrofluids. Different types and concentrations of fatty acids were reacted with the Fe₃O₄ particles, which were prepared by the coprecipitation of Fe(II) and Fe(III) salts to obtain stable Fe₃O₄ ferrofluids. The Fe₃O₄/polymer particles were monodisperse, and the composite polymer particle size was approximately 100 nm. The morphology of the magnetic composite polymer latex particles was a core–shell structure. The core was PMMA encapsulating Fe₃O₄ particles, and the shell was the P(MMA–MAA) copolymer. The carboxylic acid functional groups (COOH) of methacrylic acid (MAA) were mostly distributed on the surface of the composite polymer latex particles. Antibodies (anti‐human immunoglobulin G) were then chemically bound with COOH groups onto the surface of the magnetic core–shell composite latices through the medium of carbodiimide to form the antibody‐coated magnetic latices (magnetic immunolatices). The MAA shell composition of the composite latex could be adjusted to control the number of COOH groups and thus the number of antibody molecules on the magnetic composite latex particles. With a magnetic sorting device, the magnetic immunolatices derived from the magnetic PMMA/P(MMA–MAA) core–shell composite polymer latex performed well in cell‐separation experiments based on the antigen–antibody reaction. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1342–1356, 2005     

核壳型聚苯胺/钛酸钡的结构及其电流变性能

用改进的溶胶-凝胶法制备了核壳型聚苯胺/钛酸钡复合微粉,通过TEM及FT-IR分析表征了其形貌及微观结构,用复合微粉与氯化石蜡油配制成无水电流变(ER)液,研究其不同膜厚核壳粒子的电流变性能.研究结果表明,聚苯胺/钛酸钡复合粒子配置成的电流变液的电流变性能较纯聚苯胺的为强;钛酸钡的涂层厚度对复合粒子电流变性能有重要影响;并在d=20 nm时获得最佳电流变性能.     

A versatile surfactant‐mediated synthetic route to gold/polyaniline derivative core/shell nanocomposites

This article describes a versatile two‐step method for gold/polyaniline derivative core/shell nanocomposites with the aid of nonionic surfactant F127. First, F127 and monomer were introduced to gold colloids followed by the addition of oxidant to initiate the polymerization of monomer to afford a conducting polymer shell around each gold nanoparticle. Experimental parameters, such as kinds and concentrations of surfactant and monomer, gold core size and shape, reaction time, were systematically investigated to disclose the underground mechanisms involved in the formation of gold/polymer core/shell nanocomposites. Furthermore, Fourier transform infrared, ultraviolet–visible, X‐ray diffraction, and X‐ray photoelectron spectroscopy techniques were used to characterize the gold/polymer core/shell nanocomposites. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3903–3912, 2010     

Miniaturization of anisotropic composite particles incorporating a silica particle smaller than 100 nm

Two-step aqueous polymerizations with a water-soluble initiator of potassium persulfate were conducted to prepare anisotropic composite particles incorporating a silica core smaller than 100 nm. The two-step polymerization consisted of the first polymerization to coat the silica cores with cross-linked polymethylmethacrylate (PMMA) shell and the second polymerization to protrude a polystyrene (PSt) bulge from the core–shell particles. The concentration of ionic comonomer of sodium p-styrenesulfonate (NaSS) in the first polymerization was an important factor to stabilize the core–shell particles during the second polymerization as well as the first one, and an appropriate concentration of NaSS could prepare the anisotropic composite particles incorporating a single core. Another important factor for small, anisotropic composite particles was duration time for swelling the core–shell particles with the second monomer of styrene. Extension of the duration time from 2 to 4 h facilitated protrusion of the PSt bulge from the particles incorporating a 44-nm silica core. The composite particles were also employed to fabricate anisotropic hollow particles. Chemical etching of silica component in the composite particles with hydrofluoric acid successfully created anisotropic hollow polymer particles with a cavity size corresponding to the silica cores.     

Microthermal analysis of rubber-polyaniline core-shell microparticles using frequency-dependent thermal responses

Alternating current (ac) thermal microscopy and microthermal analysis have been utilized for the investigation in the surface thermal conductivity imaging and local thermal analysis (LTA) of polybutadiene-polyaniline core-shell microparticles. The significant variances of thermal conductivity and stiffness between rubber and conducting polymer revealed the remarkable responses in the microthermal analysis. The depth-dependent thermal microscopy controlled by the heating frequency distinguished the rubber core, which was buried under few micron thickness of polyaniline out layer. Local thermal analysis also demonstrated the heat penetration-dependent sensor response from the rigid polyaniline shell to soft polybutadiene core. These experimental results confirmed the core-shell structure of these microparticle materials, as well as the continuous conducting phase of polyaniline.     

Effects of surfactants on the morphology of composite polymer particles produced by two‐stage seeded emulsion polymerization

Poly(methyl methacrylate) (PMMA)–polystyrene (PS) composite polymer particles were synthesized in the presence of a surfactant by two‐stage seeded emulsion polymerization. The first stage was the synthesis of PMMA particles by soapless emulsion polymerization; the second stage was the synthesis of the PMMA–PS composite polymer particles with the PMMA particles as seeds. In the second stage of the reaction, three kinds of surfactants—sodium laurate sulfate (SLS), polyoxyethylene (POE) sorbitan monolaurate (Tween 20), and sorbitan monolaurate (Span 20)—were used to synthesize the PMMA–PS composite particles. Both the properties and concentrations of the surfactants influenced the morphology of the composite particles significantly. Core–shell composite particles, with PS as the shell and PMMA as the core, were synthesized in the presence of a low concentration of the hydrophilic surfactant SLS. This result was the same as that in the absence of the surfactant. However, a low concentration of Tween 20 led to composite particles with a core/strawberry‐like shell morphology; the core region was a PS phase, and the strawberry‐like shell was a PS phase dispersed in a PMMA phase. With an increase in the concentration of SLS, the morphology of the composite particles changed from core (PMMA)–shell (PS) to core (PS)–shell (PMMA). Moreover, the effects of a high concentration of Tween 20 or Span 20 on the morphology of the PMMA–PS composite particles were investigated in this study. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2224–2236, 2005     

Conducting polyaniline/nano-zinc phosphate composite as a pigment for corrosion protection of low-carbon steel

Zinc phosphate (Zn₃(PO₄)₂) nanocrystals were synthesized and used for making conducting polyaniline/nano-zinc phosphate composite by chemical oxidative method. The product was characterized by UV–visible absorption spectroscopy. The crystal structure, morphology and thermal stability of the product were studied by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and thermo gravimetric analysis, respectively. The epoxy-based paint containing conducting polyaniline/nano-zinc phosphate composite pigment was applied on low-carbon steel samples. Corrosion protection performance of the painted low-carbon steel samples in 3.5 mass % sodium chloride solution was evaluated using electrochemical technique. Transmission electron microscopic image revealed the formation of core shell structure of the composite. Composite was found to be more thermally stable than the conducting polyaniline. The corrosion rate of conducting polyaniline/nano-zinc phosphate-painted low-carbon steel was found to be 5.1 × 10^?4 mm per year, about 34 times lower than that of unpainted low-carbon steel and 10 times lower than that of epoxy nano-zinc phosphate paint-coated steel. The study reveals the possibility of using conducting polyaniline/nano-zinc phosphate as a pigment for corrosion protection.