乙烯和丙烯的等离子体聚合及聚合物结构的研究

<正> 文献[1—3]曾报导过应用等离子体聚合方法制备有机聚合物薄膜,为掌握等离子体聚合物的性能,进而扩展其用途,对其结构进行研究具有一定的意义。Kobayashi等研究了用内部电极等离子体装置制备的聚乙烯的结构,并指出其为交联结构,他们用同样装置研究了单体流量对丙烯聚合膜淀积速率的影响。我们用较简单的外部电容耦合式聚合装置,研究了在辉光区中乙烯和丙烯的聚合规律,并应用元素分析、红外光谱和X射线衍射法研究了聚合物的结构。     

α-蒎烯等离子体聚合及其聚合物结构研究

本文应用外部电容耦合式聚合装置,研究了α—蒎烯等离子体聚合规律。通过元素分析,裂解色谱-质谱、红外光谱和接触角测定等方法测定了聚合物的结构和性能。     

吡咯等离子体聚合及聚合物结构的研究

本文应用外部电容耦合式聚合装置,研究了吡咯等离子体聚合规律,找到了较好的聚合条件。通过元素分析、红外光谱等研究了聚合物的结构,电导率测定表明等离子体聚吡咯具有半导体性质。     

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。     

正丁胺的等离子体聚合膜性质及氢离子响应功能研究

以正丁胺为单体，采用等离子体聚合法，在盖玻片与玻璃碳及一些金属基片上得到附着性和稳定性均良好的聚合膜，红外光谱，元素分析结果和膜性质研究表明，该聚合具膜具有高度支化，交联的结构，具有良好的耐热和耐腐蚀性，以该膜为敏感材料制成的电位型化学传感器在强酸性溶液中对Ｈ＾＋离子具有超能斯特响应，且稳定性和重现性较好。     

压电-红外光谱-电化学联用技术研究邻氨基苯酚聚合过程及其膜的性质

建立了一种现场压电传感-红外反射光谱-电化学三维联用技术,并应用该技术现场监测了聚邻氨基苯酚在金电极上的沉积过程,研究了邻氨基苯酚的电氧化和电聚合性质以及聚邻氨基苯酚聚合膜在酸性介质中的电化学性质,同步获取并讨论了聚合膜质量、离子掺杂行为和聚合膜的化学结构变化等信息。结果表明,该技术有望广泛用于多种电极表面过程研究。     

丙醛的等离子体聚合以及聚合物的结构与性质初探

应用外部电容耦合式等离子体聚合方法,制得了丙醛聚合物,研究了不同的等离子体条件对丙醛的聚合行为的影响。通过元素分析、红外光谱分析、色谱-质谱联合分析、X-射线衍射、润湿性测定等手段研完发现,聚合物为无定形交联结构,表面能为41—45达因/厘米。     

应用裂解色谱-质谱法研究乙烯等离子体聚合物结构

应用裂解色谱—质谱(PGC—MS)法研究化学法和等离子体法聚合得到的聚乙烯的裂解行为。比较了两种聚合物的结构差异。探讨了等离子体聚合条件对聚合物结构的影响及其聚合反应机理。     

新型聚酰亚胺-氨酯反渗透复合膜的结构与性能

通过界面聚合方法, 将功能单体N,N′-二甲基间苯二胺(DMMPD)与多元酰氯5-氯甲酰氧基-异肽酰氯(CFIC)聚合, 制得一种耐氧化的聚酰亚胺-氨酯反渗透复合膜. 采用全反射傅里叶变换红外光谱(ATR-FTIR)和X射线光电子能谱(XPS)分析了膜活性层的化学结构, 考察了膜的耐氧化性能, 并探讨了膜活性层化学结构与膜抗氧化性能之间的关系.     

六氟丙烯的等离子体聚合和聚合物结构的研究

应用外部电容耦合式聚合装置,研究了六氟丙烯(HFP)的聚合规律,找到了较好的聚合条件。实验中发现在聚合过程中,随功率增加脱氢作用增大,这可利用氢等离子气体加以控制。X-射线衍射法和元素分析结果表明,在辉光区中形成的PHFP具有高度支化和交联的结构。从性能研究中看出,等离子体PHFP膜具有较好的光学性能,疏水性和较高的热稳定性。     

Surface modification of Kapton film by plasma treatments

Kapton films were treated with seven plasmas: Ar-, N₂-, O₂-, CO-, CO₂-, NO-, and NO₂- plasmas. Surface properties and chemical composition of the plasma-treated Kapton films were investigated from the contact angle measurement, and the IR and XPS spectra. The plasmas, especially NO- and NO₂-plasma, made the Kapton film surface hydrophilic. The XPS and IR spectra showed that the plasma led to the modification of the imide groups in the Kapton film to secondary amide and carboxylate groups.     

Oxidation of polyethylene surface by glow discharge and subsequent graft copolymerization of acrylic acid

Plasma-induced graft copolymerization of acrylic acid, which was incorporated into PE films, was investigated here. The influence of plasma conditions such as plasma treatment gases, power, pressure, time, monomer concentration, and graft copolymerization time on polymerization yield was determined. The samples were characterized by ESCA, IR, and water contact angle. A respective chemical shift of the C1s signal of Ar or O₂ plasmatreated and untreated PE films was revealed by ESCA, in which the presence of the grafted PAAc was also verified. An increase in polymerization yield with plasma treatment duration and power was found. That the grafted copolymerization was limited to a very thin surface region was revealed by optical microscopy on the cross section of the grafted film. © 1993 John Wiley & Sons, Inc.     

In situ UV-Vis and ex situ IR spectroelectrochemical investigations of amorphous and crystalline electrochromic Nb2O5 films in charged/discharged states

Niobium oxide (Nb₂O₅) films and powders have been obtained via the sol-gel route from an NbCl₅ precursor. XRD spectra revealed that films with pseudohexagonal (TT-phase) and orthorhombic (T-phase) structure were formed at 500  °C and 800  °C, respectively, while at 300  °C films were amorphous. Infrared (IR) and Raman spectra of powders and films of Nb₂O₅ in different polymorphic forms were detected, and vibrational band assignments were made. Electrochromic properties of amorphous films and films with the TT-phase were established from in situ ultraviolet visible (UV-Vis) spectroelectrochemical measurements and correlated with ex situ IR transmission spectra of charged films. Ex situ IR spectra revealed that charging of amorphous films is accompanied by variations of the Nb-O stretching mode intensity, while, for films with the TT- and T-phase, splitting of the Nb₃-O stretching modes and the appearance of polaron absorption were noted with Li⁺ ion insertion. Ex situ X-ray diffraction (XRD) spectra of charged films with the TT-phase showed changes of the unit cell dimensions with charging. The influence of the polaron absorption on the ex situ near-grazing incidence angle (NGIA) IR reflection-absorption spectra of charged/discharged films is discussed in detail. Received: 21 August 1997 / Accepted: 9 October 1997     

IR spectroelectrochemical studies of Fe2V4O13, FeVO4 and InVO4 thin films obtained via sol-gel synthesis

In this paper we generalize the IR spectroscopic properties of M³⁺VO₄ (M=Fe, In) orthovanadate and Fe₂V₄O₁₃ films. The films were prepared using the sol-gel synthesis route from M³⁺ nitrates and vanadium oxoisopropoxide. The vibrational bands in the IR absorbance spectra of the films are classified in terms of terminal V-O stretching (1050–880 cm^–1), bridging V-O^...Fe and V^...O^...Fe stretching (880–550 cm^–1), mixed V-O-V deformations and Fe-O stretching (<550 cm^–1) modes. Ex situ IR spectra of films were measured after consecutive charging/discharging to various intercalation coefficients x and correlated to the current peaks in the cyclic voltammetry curves measured in 1 M LiClO₄/propylene carbonate electrolyte. We classified the ex situ IR spectra of charged/discharged films according to their vibrational band changes. The results reveal that, for small values of the intercalation coefficient, crystalline FeVO₄, InVO₄ and Fe₂V₄O₁₃ films exhibit a simultaneous decrease in the intensity of all IR bands while the band frequencies remain unaffected. For the higher intercalation levels, IR mode frequencies are shifted, signaling the presence of reduced vanadium. Further charging leads to an amorphization of the film structure, which was established from the similarity of the IR spectra of charged films with those of amorphous films prepared at lower annealing temperatures. The results confirm that ex situ IR spectroelectrochemical measurement is an effective way to assess the structural changes in films with different levels of intercalation. Electronic Publication     

A study of the chemical bond types in films deposited from bis(trimethylsilyl)-ethylamine by PECVD

Silicon carbonitride films are synthesized by plasma enhanced chemical vapor deposition from bis(trimethylsilyl)ethylamine and helium or ammonium mixtures. The structure of chemical bonds in the films is studied by X-ray photoelectron and IR spectroscopy. The data on the main types of bonds present in silicon carbonitride films deposited under different synthesis conditions are obtained. It is shown that the use of ammonia at a low deposition temperature provides the synthesis of films with a simultaneous formation of Si-C, Si-N, and C-N bonds. The main bonds in films obtained from a bis(trimethylsilyl)ethylamine and helium mixture are Si-C and Si-N. The chemical structure of films obtained at high synthesis temperatures is close to SiC _x regardless of the type of the additional gas used.     

Preparation and characterization of plasma-polymerized N-vinyl-2-pyrrolidone films

Thin films (< 1 μm) of plasma polymerized N-vinyl-2-pyrrolidone (PPNVP) have been prepared, using an inductively coupled RF glow discharge in a flow-through reactor system. PPNVP films were hydrophilic, smooth, and appeared morphologically homogeneous. The polymer deposition rate was found to increase linearly with NVP flow rate, and to decrease with the distance from the induction coil. ATR–FT–IR spectral studies suggested a highly branched polymer structure and included absorptions at 2150 and 1540 cm^?1 which were unique to the plasma polymer and derived from lactam ring opening/breaking reactions. ESCA studies demonstrated that, under a given set of plasma reaction conditions, the surface composition was consistent throughout the reactor. However, polymer composition was influenced by larger changes in the plasma energy, since the nitrogen content was found to decrease with increasing W/FM. This corresponded to concomitant increases in the advancing water contact angles and to small but reproducible changes in the IR spectrum.     

Effects of Mg doping on the properties of highly transparent conductive and near infrared reflective Zn1−xMgxO:Ga films

Highly transparent conductive and near infrared (IR) reflective Gallium-doped ZnMgO (Zn_1−xMg_xO:Ga) films with Mg content from 0 to 10 at% were deposited on glass substrate by DC reactive magnetron sputtering. X-ray diffraction shows all the ZnMgO:Ga films are polycrystalline and have wurtzite structure with a preferential c-axis orientation. Hall measurements indicate that the resistivity of these films obviously increases with the Mg concentration increasing. The average transmittance of Zn_1−xMg_xO:Ga films is over 90% in the visible range. All the Zn_1−xMg_xO:Ga films have low transmittance and high reflectance in the IR region.     

IR Spectroscopic Investigations of Gasochromic and Electrochromic Sol-Gel—Derived Peroxotungstic Acid/Ormosil Composite and Crystalline WO3 Films

We studied the gasochromic effect of amorphous peroxopolytungstic acid (W-PTA), W-PTA (ormosil) and crystalline WO₃ films. These latter films were prepared after a heat treatment of W-PTA/ormosil films at 450°C. The ormosil served as a template, providing the monoclinic WO₃ films with adequate porosity. The spill-over effect was attained by impregnating the porous WO₃ crystalline films with H₂PtCl₆ followed by a heat treatment at 380°C. The amorphous films became gasochromic with the addition of PdCl₂ to the corresponding W-PTA and W-PTA/ormosil sols.Structural features of all the films were studied with the help of infrared (IR) spectroscopy and transmission electron microscopy (TEM). In situ IR spectra of the films, performed in the presence of reducing (H₂/Ar) and oxidising (O₂/Ar) gases, revealed a reversible transformation of the monoclinic to the tetragonal H _x WO₃ phase. At the same time the coloration (reduction) of the amorphous films was accompanied by the formation of coordinated water molecules and increased numbers of W=O bonds. Gasochromic colouring/bleaching changes and the corresponding kinetics were assessed from in situ UV-visible transmission measurements on the films.     

PE-CVD of Fluorocarbon/SiO Composite Thin Films Using C4F8 and HMDSO

Plasma copolymerization of hexamethyldisiloxane (HMDSO,(CH₃)₃-Si-O-Si-(CH₃)₃) and C₄F₈ was performed using an RF plasma enhanced chemical vapor deposition method for application to low dielectric constant intermetal dielectrics. Structure of the films was investigated by X-ray photoelectron spectroscopy and Fourier transform infrared (FT-IR) spectroscopy. The film composition was controlled gradually from fluorinated carbon to organic siloxane by changing the mixing ratio of HMDSO/Ar. Dielectric constant of the films ranged from 2–3.3. Thermal stability of the films, which was characterized by intensity loss of IR absorbance peak around 1000–1500 cm^–1 corresponding to C-F _n , Si-O-Si and Si-(CH₂)_n-Si bonds, was inferior to that from C₂F₄/HMDSO/Ar. In situ gasphase FT-IR spectroscopy revealed that there was a marked difference between the gas phase of C₄F₈/HMDSO/Ar and that of C₂F₄/HMDSO/Ar discharges. The IR spectrum of the former combination plasma contained a peak at 1250 cm^–1 with full width at half maximum as large as 150 cm^–1, which suggests that fluorocarbon particles and/or dusts are formed in the plasma. This suggests also that deposition precursors are not only CF _n (n = 1, 2, and 3) but also larger precursors such as C _x F _y (x > 1, y < 2x + 2) in C₄F₈/HMDSO/Ar discharges, which is presumably the cause of difference in thermal stability of the films prepared from C₄F₈/HMDSO/Ar and C₂F₄/HMDSO/Ar mixtures.     

Infrared dichroism and molecular conformation of crystalline tetramethyldisiloxanediol

Vibrational spectra of tetramethyldisiloxanediol (TMDD) have been studied in solution and also in the solid state. Polarized IR spectra of oriented crystalline films have been recorded in the frequency range 4000–200 cm^?1. The structure of the molecules in solution has been found to be of C_2v symmetry. On the basis of the IR dichroitic data obtained for the oriented crystalline films, the molecules should have no symmetry in crystals (C₁ site symmetry) and the structure of OC₂SiOSiC₂O skeletal fragment may be described with an angle of torsion of about 70° around the (Si)O-Si bond.