丝素蛋白膜在高电场下的介电性能

丝素蛋白的分子结构兼具软段和硬段,且其结构单元具有较大的偶极矩(3.5D),在介电储能领域可能具有应用潜力.本文表征了丝素蛋白薄膜的在高电场下的介电性能,并研究了丝素蛋白的分子结构与高电场下介电性能的关系.结果显示,丝素蛋白的二级结构变化与其高场介电行为关系密切,β-折叠结构增加有利于提高击穿强度,降低介电损耗.通过调整薄膜的制备工艺优化了丝素蛋白薄膜的高场介电性能,优化后的丝素蛋白膜在500 MV/m的电场下放电能量密度可达7.43 J/cm~3,充-放电效率为79.8%.本工作为开拓丝素蛋白在介电领域的应用提供了基础数据,并为进一步优化分子结构提供了参考.     

D_4等离子体聚合物复合膜的制备、形成过程及其氧氮分离性

<正> 将高分子膜用于气体分离已越来越受到人们的重视.在特定条件下,用等离子体聚合可形成高分子超薄膜,它有高度交联结构,表面平整、致密、无针孔.因此,将它用于气体分离是有希望的.本工作用八甲基环四硅氧烷(简称D_4)作单体,进行等离子体聚合,沉积在聚丙烯多孔底膜上,得到D_4等离子体聚合物复合膜.研究表明,该膜有较好的气体透过性能,其氧气透过速率Jo_2为0.5—2×10~(-5)cm~3(STP)/cm~2·sec·cmHg,氧氮分离系数。αo/N为3.3—3.8,远远高于用经典方法制得的聚有机硅氧烷膜的αo/N2.0.     

等离子体聚合膜的电学性质研究：Ⅰ.TCNQ聚合膜的结构和电学性质

本文采用内部电极、电容耦合式钟罩型射频等离子体聚合装置,首次进行了四氰代对二次甲基苯醌(TCNQ)的等离子体聚合,得到了电导率为10~(-8)～10~(-6)Scm~(-1)的聚合物半导体薄膜。由这些聚合物薄膜制备的Al/聚合膜/ITO(铟锡氧化物透明电极)夹层元件显示出整流特性和光生伏打效应。这种聚合物薄膜还具有光电导性质。红外光谱(IR)、紫外光谱(UV)的研究结果表明,优良的半导体特性归因于聚合膜中存在有较大范围的π电子共轭结构。     

柔性高储能P(VDF-CTFE)/PA11-g-GMA聚合膜的制备与性能研究

采用反应增容及等温拉伸技术制备了柔性高储能P(VDF-CTFE)/PA11-g-GMA聚合物薄膜.通过XRD、SEM以及电性能测试分析了聚合物薄膜的微观结构与介电性能.结果表明,经GMA接枝改性后的P(VDF-CTFE)/PA11-g-GMA聚合物薄膜两相相容性增加;经外力拉伸后,P(VDF-CTFE)/PA11-g-GMA的分子链在外力作用下被强制解缠,极性基团在外场作用下取向程度增大,增加了结晶结构中β相的含量,有效提高了s-P(VDF-CTFE)/PA11-g-GMA聚合膜的介电性能和储能密度;同时,由于外力协同分子链的运动,聚合物链段运动能力也增大,经过增容改性的聚合物薄膜介电损耗下降.因此制备了一类高储能、低损耗的柔性聚合物薄膜,耐压强度达到275 MV/m,储能密度可达8.09 J/cm3,为轻质、柔性、小型功能器件的发展奠定了基础.     

基于等离子体聚合膜固定酶的H2O2生物传感器

以玻碳电极为基础电极,用微波等离子体技术聚合沉积聚乙二胺等离子体膜,使之形成带氨基功能团的表面,再通过戊二醛交联共价固定辣根过氧化物酶,制得H2O2生物传感器.探讨了等离子体聚合膜的形成条件(如放电功率、单体流速、单体气压和聚合时间),讨论了工作电位、介体浓度和pH值对传感器响应的影响.此外,用红外光谱对等离子体聚合膜进行了表征.该传感器在5×10-7～1.1×10-3mol/LH2O2浓度范围内有线性响应,最低检测限为0.3μmol/L.将此传感器用于实际试样回收率的测定,结果良好.     

等离子体引发HEMA的RAFT接枝聚合改性聚丙烯多孔膜

采用等离子体引发的可逆加成-断裂链转移(RAFT)接枝聚合法,以甲基丙烯酸羟乙酯(HEMA)为单体,对聚丙烯(PP)多孔膜表面作了亲水改性.研究了接枝聚合动力学,并以FT-IR、SEM、压汞、水通量等方法研究了改性膜的表面结构形态及孔结构.结果表明,等离子体引发的RAFT接枝聚合速率显著低于普通等离子体引发的接枝聚合速率.表面接枝率随着接枝聚合时间的延长呈线性增长趋势,同时改性膜的孔径和水通量随之减小.     

聚喹啉/十八胺/稀土杂多阴离子杂化LB膜的制备、结构及电性质

将聚喹啉(PQ)、十八胺(OA)和含稀土元素的1;11钨系双系列杂多阴离子RE(PW₁₁O₃₉)₂^11-(RE=Ce^Ⅲ,Eu^Ⅲ,Gd^Ⅲ)通过LB技术掺杂,成功地制备了三种PQ/OA/稀土杂多阴离子杂化LB膜,通过π-A曲线、荧光、吸收光谱和原子力显微镜等手段对PQ/OA/稀土杂多阴离子杂化LB膜的成膜方式、性能、结构及形貌进行了表征;扫描隧道显微镜研究表明,将稀土杂多化合物掺杂到聚喹啉中可使聚喹啉的导电性明显增强.     

1 - 烃基异喹啉Reissert Compounds 的合成及其氢化研究

1-苄基异喹啉Reissertcompound经RaneyNi(w-2)催化氢化,分离得到二个未见报道的氢化产物,经化学和波谱分析推定其结构为:1-亚氨基-1-苄基-2-苯甲酰基-1,2-二氢异喹啉(4)和3-苯基-10b-苄基-1,10b-二氢咪唑骈[5,1-a]异喹啉(5)。据此提出了一条1-苄基异喹啉Reissertcompound高压催化氢化的途径,并对异喹啉eissertcompound高压催化氢化反应中酰基转位进行了讨论。试图以环已基溴作为烷化剂,在氢化钠条件下,与异喹啉Reissertcompound作用来制备1-环已基异喹啉Reissertcompound,结果只得到了1-氰基异喹啉,产率达75%,为制备1-氰基异喹啉提供了一个新方法。     

LaNiO3衬底上Pb(ZrxTi1－x)O3铁电薄膜及梯度薄膜的制备和研究

报道了在镍酸镧 (LaNiO₃, 简称LNO)衬底上锆钛酸铅 [Pb(Zr_xTi_1－x)O₃, 简称PZT]铁电薄膜及其成分梯度薄膜的结构、介电性能、铁电性能以及热释电性能. 首先通过金属有机化合物热分解(MOD)法在Si(100)基片上制备出LaNiO₃, 薄膜, 再通过溶胶-凝胶(sol-gel)法, 在LNO/Si(100)衬底上制备出Pb(Zr_0.80Ti_0.20)O₃, [PZT(80/20)]和Pb(Zr_0.20Ti_0.80)O₃, [PZT(20/80)]铁电薄膜及其成分梯度薄膜. 经俄歇微探针能谱仪(AES)对制备的梯度薄膜进行了成分深度分析, 结果证实成分梯度的存在. 经XRD分析表明, 制备的梯度薄膜为四方结构和三方结构的复合结构, 但其晶面存在一定的结构畸变. 经介电频谱测试表明, 梯度薄膜的介电常数比每个单元的介电常数要大, 但介电损耗相近. 在10 kHz下, 梯度薄膜的介电常数和介电损耗分别为317和0.057. 经电滞回线的测试表明, 梯度薄膜的剩余极化强度比每个单元都大, 而矫顽场却明显较小. 梯度薄膜的剩余极化强度和矫顽场分别为29.96 μC•cm^-2 和54.12 kV•cm^－1. 经热释电性能测试表明, 室温下梯度薄膜的热释电系数为5.54×10-8 C•cm^－2•K^－1, 高于每个单元的热释电系数.     

分段控温原位聚合沉积法制备苯胺-邻苯二胺共聚物薄膜

提出在玻璃基体表面原位聚合沉积制备苯胺-邻苯二胺(An-oPD)共聚物薄膜的一种方法:分段控温法,即高温预聚(高水浴温度)、低温聚合(冰水浴)。该法可在缩短聚合反应时间的同时避免暴聚现象,提高成膜效率,所得共聚物薄膜形貌特征优异、膜厚均匀;该法可制得饱和厚度120 nm,电导率9.16×10-2S/cm的An-oPD共聚物薄膜,具有与均聚PAn薄膜不同的电致变色性能。     

Deposition of plasma conjugated polynitrile thin films and their optical properties

The plasma polymerization of 4-phenylbenzonitrile was carried out with the objective of synthesizing a novel conjugated polynitrile thin film with a better optical property. The structure, compositions and morphology of the plasma-polymerized 4-phenylbenzonitrile (PPBPCN) thin films were investigated by Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). A fine, homogenous PPBPCN film with a large π-conjugated system and a high retention of the aromatic ring structure of the starting monomer in the deposited plasma films is obtained when a low discharge power of 30 W was used during film formation. For the first time, a blue emission with relatively high photoluminescence intensity for PPBPCN thin films was observed.     

Nanostructured ultra-low-κ porous fluoropolymer composite films via plasma co-polymerization of hydrophobic and hydrophilic monomers and subsequent hydrolysis treatment

A new approach to fabricate porous nanostructured fluoropolymer composite films with a low dielectric constant (κ) was put forward at the first time. Initially, a film (pp-HDFD-PEGMA film) composed of dense, uniform, and well-defined nanospheres was controllably deposited on hydrogen-terminated silicon substrates by simultaneous plasma polymerization and deposition of a fluorine-containing hydrophobic monomer, 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluoro-1-decene (HDFD), and a hydrophilic monomer poly(ethylene glycol) methacrylate (PEGMA), using a pulsed plasma polymerization technique. Then, by hydrolysing the plasma co-deposited film in aqueous hydrochloric acid solution to effectively remove the soluble nanospheres or fragments which mainly derived from PEGMA, a nanoporous fluorocarbon film was achieved. Subsequently, a top poly(tetrafluoroethylene) layer was deposited via the magnetron sputtering process to cap and complete an encapsulated structure. The resulting bilayer composite film consisting of a layer of nanostructured fluorocarbon porous film and a layer of encapsulation fluorocarbon polymer has a κ value of 1.8. The morphology investigation of the plasma co-deposited film prior and after acid-treatment by field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM) confirmed the form of the nanospheres and nanoporous structure, while the chemical composition and structure analysis by X-ray photoelectron spectroscopy (XPS) revealed that after the acid-treatment, the porous nanostructured film are composed predominantly of mainly fluorocarbon polymer.     

Atmospheric Pressure Plasma Deposition of Polyfuran

The atmospheric pressure radiofrequency (RF) plasma polymerization of furan was carried out with the objective of synthesizing polyfuran thin film. The structure, compositions and morphology of the plasma deposited polyfuran film were investigated by Fourier transform infrared (FTIR), atomic force microscopy (AFM), ultraviolet‐visible absorption spectroscopy (UV‐vis) and thermogravimetric analysis (TGA). The formation of polyfuran was confirmed using FTIR and UV‐visible analysis. The properties of plasma‐deposited polyfuran were compared with those of chemically synthesized polyfuran. Although the plasma deposited thin film polyfuran shows lower thermal stability than that of chemically synthesized polyfuran. It has better solubility in CHCl₃, also. Thin uniform polyfuran films are obtained in plasma assisted polyfuran deposition, while particles are obtained in chemical polyfuran polymerization.     

Deposition of π-Conjugated Polycyanate Ester Thin Films and Their Dielectric Properties

Two kinds of novel π-conjugated polycyanate esters, namely the plasma-polymerized 4-methoxyphenol cyanate ester (PPMPCE) and the plasma-polymerized 4-phenylphenol cyanate ester (PPPPCE), were successfully prepared by plasma polymerization for the first time. The structure and compositions of both plasma polycyanate esters were investigated by Fourier Transform Infrared (FT-IR), X-ray Photoelectron Spectroscopy (XPS) and UV–Visible Absorption Spectra (UV–Vis). The results show that extensively conjugated C=N double bonds were formed in the plasma-deposited cyanate ester thin films, the plasma polymerization of both monomers proceeded mainly via the opening of π-bonds of the O–C≡N functional groups which are further on being formed into a large π-conjugated system, this unique process is noticeably different from the conventional thermal polymerization reaction of cyanate ester monomers. Further dielectric measurement shows that PPPPCE thin film gives a lower dielectric constant comparing to that of the PPMPCE film, and the dielectric constant of both plasma deposited thin films decreased with an increase in measurement frequency.     

Plasma polymerization and deposition of glycidyl methacrylate on Si(100) surface for adhesion improvement with polyimide

Thin polymer films were deposited on Si(100) surfaces by plasma polymerization of glycidyl methacrylate (GMA) under different glow discharge conditions. The FT‐IR, X‐ray photoelectron spectroscopy (XPS), and amine treatment results suggested that the epoxide functional groups of the deposited films had been preserved to various extents, depending on the plasma deposition conditions. The use of a low radio frequency power (～ 5 W) and a relatively high system pressure (100–400 Pa) readily resulted in the deposition of thin films having nearly the same composition of the epoxide functional groups as that of the GMA homopolymer. The plasma‐polymerized GMA (PP‐GMA) thin films deposited on the Ar plasma‐pretreated Si(100) surfaces were retained to a large extent after acetone extraction, suggesting the presence of covalent bonding between the PP‐GMA layer and the Si surface. Thermal imidization of the poly(amic acid) precursor of polyimide on the GMA plasma‐polymerized Si(100) surface resulted in a strongly adhered polyimide film. The adhesion results further suggested that the GMA polymer had been grafted on the Si(100) surface and the epoxide functional groups had undergone reactive interaction (curing) with the carboxylic and amine groups of the poly(amic acid) during thermal imidization. Copyright © 2001 John Wiley & Sons, Ltd.     

Plasma polymerization. VI. An ESCA investigation of the RF plasma polymerization of perfluoro-2-butyl tetrahydrofuran

Perfluoro-2-butyl tetrahydrofuran was polymerized by an RF glow discharge technique and detailed ESCA studies were made of the resultant films. The rate of film deposition was sensitively dependent on the W/FM parameter and the site of deposition. The ESCA data show that the molecular rearrangement accompanying plasma polymerization and the oxygen functionality is at a significantly lower level than the starting material. Under appropriate conditions plasma polymerization produces material with a C:F stoichiometry of 1:2, although the ESCA data show that the polymer is drastically different from PTFE. ESCA studies are also reported on thin films of the monomer studied at low temperature.     

Electroluminescence and Photoluminescence of Conjugated Polymer Films Prepared by Plasma Enhanced Chemical Vapor Deposition of Naphthalene

Polymer light-emitting devices were fabricated utilizing plasma polymerized thin films as emissive layers. These conjugated polymer films were prepared by RF plasma enhanced chemical vapor deposition using naphthalene as monomer. The effect of different applied powers on the chemical structure and optical properties of the conjugated polymers was investigated. Fourier transform infrared (FTIR) and Raman spectroscopies confirmed that a conjugated polymer film with a 3-D cross-linked network was developed. By increasing the power, products tended to form as highly cross-linked polymer films. The fabricated devices showed broadband Electroluminescence (EL) emission peaks with center at 535–550 nm. Photoluminescence (PL) spectra of plasma polymers showed different excimeric emissions, resulted from crosslinked architecture. As the plasma power increased, the optical properties showed two different domains; up to 200 W, EL, PL and UV–Vis spectra red-shifted and broadened significantly. At higher powers, a reverse behavior was observed. Also, the relation between the film structure and plasma species was investigated using optical emission spectroscopy.     

Increasing the Hydrophobicity of a PP Film Using a Helium/CF<Subscript>4</Subscript> DBD Treatment at Atmospheric Pressure

Plasma surface modification is widely used to tailor the surface properties of polymeric materials. Most treatments are performed using low pressure plasma systems, but recently, atmospheric dielectric barrier discharges (DBDs) have appeared as interesting alternatives. Therefore, in this paper, an atmospheric He + CF₄ DBD is used to increase the hydrophobicity of a polypropylene (PP) film. The surface characterization of the PP film is performed using contact angle measurements, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Results show that the hydrophobic properties of the polymer films are greatly enhanced after plasma treatment as evidenced by an increased contact angle. The incorporation of fluorine on the surface is significant (45 at%), demonstrating the ability of the used DBD set-up to generate fluorine-containing functional groups on the PP surface.     

Pulsed‐laser–deposited and plasma‐polymerized polytetrafluoroethylene (PTFE)‐like thin films: A comparative study on PTFE‐specific properties

Glass‐like and structural first‐order phase transitions are investigated in polytetrafluoroethylene (PTFE) foils and PTFE‐like films prepared by pulsed‐laser deposition (PLD) and plasma polymerization (PP). A structural comparison of the investigated polymers is performed by infrared spectroscopy and dielectric dilatometry. It is shown that dielectric dilatometry (the measurement of the susceptance vs. temperature) provides a simple and elegant means for detecting volumetric transitions in thin nonpolar polymer films. In conventional PTFE foils, the known glass‐like and structural first‐order phase transitions are identified. The structure of pulsed‐laser deposited PTFE strongly depends on the target material, ranging from highly crystalline films showing only structural phase transitions to films strongly deviating from PTFE foils, with structural characteristics comparable to plasma‐polymerized fluorocarbons. The dielectric loss of the highly crystalline PLD films compares favorably with conventional PTFE foils, making the films attractive for new applications in miniature electret devices. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 2115–2125, 1999     

Role of Plasma Parameters on the Conjugated Structure Retention in Polyaniline Thin Film

The role of plasma parameters on the film characteristics is investigated on polyaniline thin film deposited by radio frequency (RF) plasma polymerization. A series of un-doped and iodine doped polyaniline thin films are prepared by RF discharge operating at 13.56?MHz with different discharge powers and pressure variation from 0.1 to 0.05?mbar and variation in deposition time from 20 to 40?min. A good thin film is found with a power ranging from 9?W (?28?V self bias) to 20?W (?65?V self bias) at 0.1?mbar pressure which is confirmed by fourier transform infra-red spectroscopy showing the retention of aromatic rings. In addition, iodine doping is carried out with 9?W power and 0.1?mbar pressure. The characterization of process plasma is done using Langmuir probe diagnostics and optical emission spectroscopy. A correlation has been established between film characteristics and plasma properties investigated using optical emission spectroscopy and Langmuir probe analysis. Emphasis has been given on the study of the influence of plasma parameters, particularly of the electron energy distribution function on the quality of conjugated plasma polymerized aniline film.