聚1,5-萘二胺膜修饰电极电化学传感器的研究进展

聚萘二胺作为导电聚合物的一种,其性能在某些方面要优于传统的导电聚合物,有望成为一种新型的具有广阔应用前景的功能材料.本文综述了循环伏安法制备聚1,5-萘二胺的电化学行为以及电化学过程中可能产生的聚合物结构.阐述了聚1,5-萘二胺膜修饰电极的化学和生物探测应用.对聚1,5-萘二胺在传感器的应用和发展等方面进行了展望.     

高导电率聚吡咯薄膜制备工艺探究

通过化学原位聚合的方法将聚吡咯沉积于石英基片表面制备导电薄膜,探讨了硅烷偶联剂溶液中的浸渍时间、吡咯溶液的浓度、氧化剂用量、最后一次在FeCl_3溶液中的浸入时间等参数对薄膜导电性的影响。结果表明:硅烷偶联剂KH-550的浸渍时间为10min,吡咯乙醇的体积比为1∶2,Fe Cl3的浓度为30%,三次氧化聚合时最后在氧化剂FeCl_3溶液的浸入时间为50min时,薄膜的导电率达到最大7.47S/cm。     

水介质中2,6-二甲基苯酚氧化聚合制聚苯醚

研究了全水介质中2,6-二甲基苯酚(DMP)氧化聚合过程中聚合物粒子粒径随反应时间的变化,结果发现DMP在全水介质中的氧化聚合属于沉淀聚合,可分为齐聚物沉析成核、一次聚并、二次聚并3个阶段.DMP氧化聚合过程中引入溶胀剂苯乙烯,可提高PPO的相对分子质量,这是由于苯乙烯的引入能增加聚合物粒子相内预聚物分子链的活动性,促进聚合物粒子相内的后氧化聚合.     

水介质中铁氰化钾作用下2,6-二甲基苯酚氧化聚合初始动力学

采用电化学方法研究了水介质中铁氰化钾作用下2,6-二甲基苯酚(DMP)氧化聚合初始动力学,确定了各反应参数对DMP氧化聚合的影响。发现DMP聚合初始速率随DMP和铁氰化钾浓度的增加而增加,DMP聚合初始速率与DMP浓度的一次方呈正比,与铁氰化钾浓度的二次方呈正比。DMP聚合初始速率随NaOH浓度的增加而增加,这是因为DMP的氧化电位随NaOH浓度的增加而降低,DMP聚合初始速率与NaOH浓度的二次方呈正比。DMP聚合初始速率随温度的升高而增加,根据初始速率求出了不同温度下DMP聚合初始速率常数,并由Arrhenius方程求得DMP氧化聚合的表观活化能为47.7kJ·mol-1。最后根据Arrhenius方程和聚合初始速率与反应物浓度的关系建立了DMP聚合初始动力学模型,并验证了模型的正确性。     

功能性氮杂环芳胺聚合物的合成及应用

阐述了氮杂环芳胺聚合物的2种合成方法——化学氧化聚合法和电化学氧化聚合法的聚合规律,列出了氮杂环芳胺聚合物的特性,展望了氮杂环芳胺聚合物在二次电池、修饰电极、重金属离子吸附剂、橡胶抗氧剂等方面的应用前景。     

聚{3-[（3-甲氧基-3-丙酮基）硫甲基]噻吩}的合成

采用FeCl3化学氧化聚合法合成聚{3-[（3-甲氧基-3-丙酮基）硫甲基]噻吩}的合成,用红外光谱,紫外-可见光谱和核磁共振光谱进行了结构的表征。PST具有好的溶解性和成膜性,聚合物膜的最大吸收峰位于419nm,比聚合物溶液的吸收峰红移了12nm,结果表明PST在形成薄膜时共轭程度增加。     

聚吡咯—氯化聚乙烯导电材料的制备

采用现场化学氧化聚合方法,制得性能优良的粉末状聚吡咯(PPY)-氯化聚乙烯(CPE)导电材料。对合成反应的各种影响因素进行了研究,并考查了导电材料的某些性能。该导电材料具有较好的加工稳定性,可望用于电磁屏蔽等领域。     

用聚3,4-乙撑二氧噻吩对聚丙烯腈进行导电改性的研究

采用原位化学氧化聚合方法在聚丙烯腈纤维表面生成聚3,4-乙撑二氧噻吩,制备得到纤维表面均匀覆盖聚3,4-乙撑二氧噻吩的改性导电纤维,其电导率约为1×10-3S/cm。纤维表面与导电聚合物的相互作用改善了原纤维的耐热性能,并对其力学性能没有造成伤害。     

聚苯胺/聚乙烯醇微乳液导电涂料的研制及其性能的测试

采用氧化聚合方法合成可溶性的聚苯胺/聚乙烯醇(PAn/PVA)复合导电涂料.研究了反应体系中聚苯胺的含量、反应时间、温度及酸浓度对导电涂料电导率的影响,确定了较佳的聚合反应条件,同时对其稳定性、导电性、力学性及其表面结构等进行了测试.结果表明,PAn/PVA导电涂料稳定性好,在空气中放置80h电导率无明显变化,涂料涂层的电导率最高可达4.57s/cm,加入环氧树脂可明显改善涂层的附着力.     

苯胺在聚醋酸乙烯酯中的聚合研究

以过硫酸铵为氧化剂,十二烷基苯磺酸为掺杂剂,将苯胺在聚醋酸乙烯酯(PVAc)基质中进行原位氧化聚合,制备导电聚苯胺PAn/PVAc复合材料,采用溶液浇铸法制成可溶性导电复合膜,电导率达10-2s/cm。考察了反应条件对复合膜电导率的影响,并进行了环境稳定性测试,用红外光谱进行了复合膜的结构表征,用扫描电镜对复合膜的表面形态进行了观察。     

丙烯酸丁酯细乳液单电子转移-蜕化链转移聚合反应

单电子转移-蜕化链转移(SET-DT)聚合是一种单体适用性广、对聚合环境要求不苛刻的活性自由基聚合方法。以Na_2S_2O_4为催化剂,CHI3为引发剂,采用水相细乳液聚合法进行丙烯酸丁酯(BA)的SET-DT活性自由基聚合,考察了聚合温度、引发剂/催化剂浓度、催化剂滴加方式和乳化剂浓度对聚合动力学、聚丙烯酸丁酯(PBA)数均分子量和分子量分布的影响。结果表明,细乳液聚合速率明显大于悬浮聚合,可在较低温度(30℃以下)、较低引发剂和催化剂浓度(BA,CHI_3和Na_2S_2O_4的初始摩尔浓度比为1 600:1:8)下实现BA的快速聚合;通过聚合过程滴加Na_2S_2O_4催化剂和增加十二烷基硫酸钠主乳化剂浓度,可提高聚合速率;采用低引发剂浓度和催化剂逐步滴加聚合得到的PBA的平均分子量较大,分子量分布较窄。     

A comparative study on effects of two kinds of polymerization methods on grafting of polymer onto silica surface

In this article we present the result of a comparative study of two kinds of polymerization methods—solution polymerization (sol. poly.) and dispersion polymerization (dis. poly.) for grafting polymer onto silica. As a model for the grafting polymerization reaction, styrene was chosen as the monomer and azo diisobutyronitrile (AIBN) as the initiator. The study aims at supplying theoretical reference for better selecting polymerization method to graft polymer on the silica particle surface. First, monolayers of 3‐methacryloylpropyl trimethoxysilane were chemically bonded onto the surfaces of micrometer‐sized silica gel particles, and so double bonds were immobilized onto the silica surface. Second, the copolymerizations between the immobilized double bonds and the monomer styrene were carried out, homopolymerizations of styrene followed, and finally polystyrene was grafted to the silica surfaces. Two kinds of polymerization methods, sol. poly. and dis. poly., were adopted respectively, and the effects of polymerization methods on grafting process were examined mainly. At the same time, the effects of different polymerization conditions on the grafting degree were researched. It was found that in the dis. poly. system the grafting degree is obviously higher than that in the sol. poly. system under the same polymerization conditions, and the grafting degree can go up to 47%, i.e. 47g/100g. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5808–5817, 2006     

Study of optically active methacrylates containing 1,1′‐binaphthyl side‐groups polymerized by anionic,group transfer and free radical methods

Optically active and racemic poly(meth)acrylates with pendant 1,1′‐binaphthalene moiety of 2‐methacryloyloxy‐ and 2‐acryloyloxy‐2′‐methoxy‐1,1′‐binaphthalene (MAMBN and AMBN) were synthesized by anionic, group transfer and free radical polymerization methods. Their polymerizability and chiroptical properties are somewhat different, depending on the three types of polymerization methods used. The yields for poly(MAMBN)s are lower than for poly(AMBN)s. The optical rotation of the optically active polymers is identical to that of the corresponding monomers. The values of specific rotation of optically active poly(AMBN)s are much larger than those of optically active poly(MAMBN)s. © 2002 Society of Chemical Industry     

聚乳酸熔融缩聚的研究

综述了近年来国内外聚乳酸熔融聚合的研究情况,概述了直接熔融缩聚、熔融-固相和熔融-扩链合成聚乳酸的研究,并研究探讨了熔融聚合中影响聚乳酸相对分子质量的因素。     

Ring-opening polymerization of γ-benzyl-l-glutamate-N-carboxyanhydride in ionic liquids

This work deals with ring-opening polymerization of a representative N-carboxy-α-amino acid anhydride (NCA) in ionic liquids. The polymerization of γ-benzyl-l-glutamate-N-carboxyanhydride (BLG-NCA) with n-butylamine as an initiator in an ionic liquid ([BMI][PF₆]) proceeded as a milky white dispersion with no evidence of macroscopic precipitation. The polymerization with the primary amine under suitable conditions afforded poly(amino acid) having narrow polydispersity, molecular weights close to the theoretical values, and helical secondary structure. The polymerization rate was slightly affected by the nature of the anion and hydrophobicity of the ionic liquids, while poly(BLG)s having low polydispersities were obtained regardless of the kind of the ionic liquids. Several parameters, such as the existence of organic solvent as a co-solvent and monomer concentration, had also clear effects on the polymerization rate and/or the polydispersity of the resulting poly(BLG)s. The possible interactions between the ionic liquid and NCA monomer or the ionic liquid and the initiator were characterized using FT-IR, ¹H and ¹³C NMR measurements. The character of this polymerization process was also studied by performing kinetic investigations. We believe that this represents the first report on amine-initiated ring-opening polymerization of NCA in ionic liquid.     

Anionic ring‐opening polymerization of adipic anhydride initiated by potassium poly(ethylene glycol)ate

Poly(adipic anhydride) (PAA) was prepared by the ring‐opening polymerization of adipic anhydride (AA) initiated by potassium poly(ethylene glycol)ate. The effects of various factors, such as the amount of initiator, concentration of the monomer, reaction time and temperature, and polarity of the solvent on the polymerization were investigated. The crude polymerized product was a mixture of PAA homopolymer and poly(ethylene glycol)–poly(adipic anhydride) block copolymer, as confirmed by ¹H‐NMR and gel permeation chromatography. Chain‐transfer reactions occurred intensively for the AA polymerization in both the nonpolar solvent toluene and the polar solvents CHCl₃ and tetrahydrofuran, which predominantly determined the molecular weight and the monomer conversion for the polymerized product. The lower monomer conversion in toluene was ascribed to a lower livingness for the initiator in the nonpolar solvent when compared with other two, polar solvents. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2194–2201, 2003     

Emulsion polymerization of styrene with amphiphilic random copolymer as surfactant: Predominant droplet nucleation

Amphiphilic random copolymer consisting of monomeric units of poly (butyl acrylate) and poly (maleic acid salt) was synthesized and characterized. The emulsion polymerization kinetics of styrene stabilized by this copolymer was investigated. The influencing factors, including polymeric surfactant concentration, initiator concentration and polymerization temperature, were systematically studied. The kinetic data show that the polymerization rate (R_P) increased with the increase of the polymeric surfactant concentration ([S]) and polymerization temperature (T). At the higher [S], droplets nucleation and micelle nucleation coexisted in the polymerization system; at the lower [S], only the droplets nucleation process existed. The polymerization did not follow Smith‐Ewart Case II kinetics. Dynamic light scatter and transmission electron microscope were utilized to measure the sizes and shapes of the particles, respectively. It would be speculated that a kind of large heterogeneous particles with multiple‐active‐sites was formed in the polymerization system. The increasing of R_P with increasing initiator concentration ([KPS]) was rapid at a medium [KPS], but the slowly increasing was observed at a lower or higher [KPS]. It was attributed to the barrier effect of the polymeric surfactant around the monomer droplets. The polymerization activation energy was 60.29 kJ/mol. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Synthesis of high-molecular weight poly(vinyl alcohol) by low-temperature emulsifier-free emulsion polymerization of vinyl acetate and saponification

High-molecular weight (HMW) poly(vinyl alcohol) (PVA) was prepared via an emulsifier-free emulsion polymerization of vinyl acetate (VAc) using a redox initiation system in low temperatures, and the subsequent saponification with potassium hydroxide in methanol. The effect of the polymerization conditions on the conversion, molecular weight, and branching degree was investigated. PVA with maximum viscosity-average degree of polymerization (DP) of 8270 could be prepared by saponification of poly(vinyl acetate) (PVAc), with DP of 10,660 obtained at temperature of 10°C, monomer concentration of 30%, potassium persulfate molar ratio to monomer of 1/2000, agitation speed of 160 rpm. The conversion was above 90%. From the emulsifier-free emulsion polymerization of VAc in low temperature, PVAc with HMW and high linearity was effectively prepared, which might be useful for the preparation of high-strength and high-modulus PVA fiber. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Bulk polymerization of methyl methacrylate initiated by high intensity ultrasonic irradiation and ESR study

High‐intensity ultrasound was used to initiate the bulk polymerization of methyl methacrylate. The polymerization rate varied with the sonication time, the intensity of the ultrasound, and the initiator concentration of poly (methyl methacrylate) in the monomer. Electron spin resonance (ESR) spectra, obtained by the spin trapping technique, testified that free radicals were produced during the sonication process, and the concentration of radicals also changed with the sonication condition. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1731–1735, 2002     

Modified frontal polymerization of poly(methyl methacrylate)

In this work, we propose a modified frontal polymerization method to build a uniform reaction front by gradually immersing the reacting mixture in a thermal bath. This scheme allows uniform materials to be obtained with nearly constant molecular weights and polydispersities and a low residual monomer concentration. A comparative study of the molecular weight distributions of poly(methyl methacrylate)s obtained by bulk polymerization, frontal polymerization, and frontal polymerization with the proposed gradual immersion is presented. Samples obtained by these methods show that materials obtained by bulk polymerization and by frontal polymerization are less uniform than those obtained by frontal polymerization with gradual immersion in a thermal bath. The obtained uniformity is directly related to a stabilizing effect of the reaction front by the gradual immersion of the reactor in a constant‐temperature bath and to a reduction in the reaction rate promoted by a moderate transfer agent concentration. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010