A novel photosensitive ternary complex consisting of phenol‐formaldehyde resin,sodium dodecyl sulfate,and diazo resin

A novel photosensitive ternary complex formed from phenol‐formaldehyde resin (PR), sodium dodecyl sulfate (SDS), and diazo resin (DR) was developed. In the presence of SDS, PR remains soluble in water when its solution is neutralized. The PR‐SDS‐DR ternary complex forms when DR is added to the PR‐SDS solution. The ternary complex dissolves in polar solvents such as dimethylformamide and is sensitive toward UV light or heating. It was confirmed that the ionic bond of  SO +N₂ between SDS and DR converts to a covalent bond after the decomposition of the ⁺N₂ group under UV irradiation or heating. As a result, the solubility of PR‐SDS‐DR changes dramatically; that is, after treatment with UV light or heating, PR‐SDS‐DR becomes insoluble in polar solvents. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2566–2571, 2000     

Adsorption of Cationic Laser Dye onto Polymer/Surfactant Complex Film

Fabrication of complex molecular films of organic materials is one of the most important issues in modern nanoscience and nanotechnology. Soft materials with flexible properties have been given much attention and can be obtained through bottom up processing from functional molecules, where self-assembly based on supramolecular chemistry and designed assembly have become crucial processes and technologies. In this work, we report the successful incorporation of cationic laser dye rhodamine 6G abbreviated as R6G into the pre-assembled polyelectrolyte/surfactant complex film onto quartz substrate by electrostatic adsorption technique. Poly(allylamine hydrochloride) (PAH) was used as polycation and sodium dodecyl sulphate (SDS) was used as anionic surfactant. UV-Vis absorption spec-troscopic characterization reveals the formation of only H-type aggregates of R6G in their aqueous solution and both H- and J-type aggregates in PAH/SDS/R6G complex layer-by-layber films as well as the adsorption kinetics of R6G onto the complex films. The ratio of the absorbance intensity of two aggregated bands in PAH/SDS/R6G complex films is merely independent of the concentration range of the SDS solution used to fabricate PAH/SDS com-plex self-assembled films. Atomic force microscopy reveals the formation of R6G aggregates in PAH/SDS/R6G complex films.     

Development of a durable fiber-optic oxygen sensor for harsh underground environments

This paper focuses on effects of protection with a silicone resin to develop a fiber-optic oxygen sensor with long-term stability and durability in harsh underground environments. Ruthenium (II) complexes were used as oxygen-sensing compounds. A uniform composite film composed of silicone resin and the Ru complex was prepared with spin coating technique. A comparison of dissolved-oxygen (DO) sensitivity between the composite film and a Ru complex film was made by exposing to hot water (80 °C). The result of the accelerated degradation test showed that sensitivity of the Ru complex film was stable; meanwhile that of the composite film increased with exposure time in a short period. In order to improve stability, the Ru complex film overcoated with silicone resin was prepared. Differences in sensitivity for saturated DO (8.5 ppm) between with and without the silicone resin overcoating on the Ru complex film were investigated by exposing to the hot water and simulated underground water. These results revealed that the sensitivities and response times of the overcoated films were stable and slow, respectively, compared to those of non-overcoated films. Then, optodes were evaluated for effects of the overcoating on sensing properties by exposing to 100 vol.% oxygen gas. The experiment showed that: (1) the response time was significantly influenced by the thickness of the overcoating; and (2) response speed of the overcoated optode was slow by a factor of about 35 compared to that of the non-overcoated. We concluded that the overcoating was effective in the application to mid- and long-term oxygen monitoring in the harsh environments.     

Disjoining pressure and stratification in asymmetric thin-liquid films

We directly measure, for the first time, disjoining pressure isotherms for asymmetric oil/aqueous surfactant/gas (i.e., pseudoemulsion) films using a modified version of the porous-plate technique first developed by Mysels in conjunction with thin-film interferometry. Dynamic film-thinning experiments are also performed on individual foam and pseudoemulsion films. At SDS surfactant concentrations above the critical micelle concentration (CMC) (0.1 M SDS), the pesudoemulsion films exhibit the same step-wise layer thinning observed in foam films under similar conditions. Further, we conduct dynamic thinning experiments on solid/liquid/gas systems and show that aqueous 0.2 M CTAB films sandwiched between glass and air also display discrete thinning transitions. All of these stratification transitions arise from oscillations in the disjoining pressure isotherm, generated by amphiphilic structuring within the film.For 0.1 M SDS dedecane/air pesudoemuslion films, the slope and peak height of the disjoining-pressure oscillations increase with each subsequent amphiphilic layer as film thickness decreases. Magnitudes of the structural forces are low (<100 Pa) but the length scale of the oscillations is large (10 nm) and rathe far reaching (50 nm). Moreover, for 0.1 M SDS solutions, the capillary pressures associated with film rupture are significantly lower for pseudoemulsion films (0.1 kPa) when compared to foam films (15 kPa) at equivalent conditions. Taken together, our dynamic thinning and equilibrium disjoining pressure measurements indicate that stratification in 0.1 M SDS films has little effect on both kinetic and thermodynamic films stability.     

Gas permeability in polymer- and surfactant-stabilized bubble films

The gas permeabilities of thin liquid films stabilized by poly(N-isopropylacrylamide) (PNIPAM) and PNIPAM-SDS (sodium dodecyl sulfate) mixtures are studied using the "diminishing bubble" method. The method consists of forming a microbubble on the surface of the polymer solution and measuring the shrinking rates of the bubble and the bubble film as the gas diffuses from the interior to the exterior of the bubble. PNIPAM-stabilized films exhibit variable thicknesses and homogeneities. Interestingly, despite these variable features, the gas permeability of the film is determined principally by the structure of the adsorbed polymer layer that provides an efficient gas barrier with a value of gas permeability coefficient that is comparable to that of an SDS Newton black film. In the presence of SDS, both the film homogeneity and the gas permeability coefficient increase. These changes are related to interactions of PNIPAM with SDS in the solution and at the interface, where coadsorption of the two species forms mixed layers that are stable but that are more porous to gas transfer. The mixed PNIPAM-SDS layers, studied previously for a single water-air interface by neutron reflectivity, are further characterized here in a vertical free-draining film using X-ray reflectivity.     

Adsorption of Polycation and Anionic Surfactant onto Iron Surfaces and the Inhibition of Carbon Dioxide Corrosion

The adsorption process of two polycations (pDADMAC and C‐PAM) with different charge densities has been investigated using the quartz crystal microbalance technique with dissipation monitoring (QCM‐D). The effect of the charge density of the polycation, the NaCl concentration, and the complexation with an anionic surfactant are addressed in this work. X‐ray photoelectron spectroscopy and atomic force microscopy were utilized to analyze the adsorbate with respect to the film coverage and film structure. The corrosion‐inhibiting performance of the films on high‐purity iron in a CO₂ saturated brine, at 25°C, 1 bar CO₂, and pH 4, was investigated by the linear polarization resistance technique. It was found that the polycations adsorbed onto the iron surface, but the corrosion rate of 1 mm yr^?1 was not lowered. However, the polycations formed a complex with an anionic surfactant, and such films showed excellent inhibition performance. Both films, of pDADMAC/SDS and of C‐PAM/SDS, lowered the corrosion rate of iron below 0.01 mm yr^?1. The SDS concentration was below the cmc. It is believed that the SDS adsorbed into the preadsorbed polycation film, forming a complex structure resulting in a hydrophobic and dense film.     

重氮树脂—聚磷酸复合物

带有相反电荷 (通常在侧链 )的聚电解质 ,通过静电相互作用形成的复合物 ,称聚电解质复合物 (ＰＥＣ) .ＰＥＣ已有很多研究[1～ 3] ,也有一些应用的报道[4,5] .重氮树脂 (ＤＲ) ,一种由二苯胺 4 重氮盐与多聚甲醛在浓硫酸中缩合得到的缩聚物[6] ,因侧链带重氮基 ,所以是正离子聚电解质 .它能与各种负离子聚电解质生成感光性的ＰＥＣ ,并可用作光成像体系的感光剂[7,8] .ＤＲ与聚磷酸 (ＰＰＡ)生成重氮基为正离子 ,磷酸基为负离子的复合物 ,这种复合物文献上未有过报道 .本文初步研究了这种复合物的制备与性质 .1　重氮树脂 聚磷酸复合物 (…     

AFM morphological study of electropolymerised polyaniline films modified by surfactant and large anions

Atomic force microscopy (AFM) ex situ experiments were carried out in order to study morphologies of polyaniline films grown in the presence of an anionic surfactant, sodium dodecylsulphate (SDS), and also using different functionalised organic acids. Polyaniline film morphologies obtained in the presence of SDS were analysed in terms of the formation of a complex between the rodlike micelles and the anilinium cation in solution. For the different acids, the influence of anion size and the solubility of the oligomeric salt were considered to explain the different sizes of globular morphologies.     

Incorporation of water-soluble and water-insoluble ruthenium complexes into zirconium phosphate films fabricated by the layer-by-layer adsorption and reaction method

Water-soluble tris(2,2'-bipyridine)ruthenium(II) complex (Rubpy) and water-insoluble tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(II) complex (Rudpp) were successfully incorporated into zirconium phosphate (ZrPS) films fabricated by a facile layer-by-layer (LbL) adsorption and reaction method. Rubpy-incorporated ZrPS films were fabricated by the LbL adsorption and reaction method employing a mixture solution of Rubpy and phosphate salt. Rubpy was incorporated into ZrPS films during the formation of ZrPS layers because of the electrostatic interaction between them. Rudpp was dissolved in the mixture solution of aqueous phosphate salt and ethanol and was incorporated into ZrPS films through the formation of ethanol preintercalated ZrPS layers. The successful incorporation of Rubpy and Rudpp into ZrPS films was confirmed by UV-vis absorption spectroscopy. Rubpy and Rudpp have concentrations of 0.915 x 10 (14) and 3.23 x 10 (14) molecules/cm (2) in each ZrPS layer, respectively. Scanning electron microscopy measurements indicate that the as-prepared Rubpy-incorporated ZrPS films are smooth while the as-prepared Rudpp-incorporated ZrPS films are porous. The porous Rudpp-incorporated ZrPS films are suitable to use as oxygen sensors because the luminescence of Rudpp incorporated into the ZrPS films can be quenched by oxygen and the porous film structure facilitates the permeation of oxygen into and out of the film.     

Two-dimensional surface properties of PEO-PPO-PEO triblock copolymer film at the air/water interface in the absence and presence of Tyr-Phe dipeptide, Val-Tyr-Val tripeptide, SDS and stearic acid

Two-dimensional surface properties of PEO-PPO-PEO triblock copolymer film (Mol.Wt. 2800) in the absence and presence of Tyr-Phe dipeptide, Val-Tyr-Val tripeptide, sodium dodecylsulfate and stearic acid have been investigated for the first time at the air/water interface using Langmuir film balance technique. It is observed that the above polymer forms fairly stable film at the air/water interface. There are no significant changes observed in the surface pressure-area (π-A) isotherms of polymer in the presence of SDS. However, more expanded film was formed in presence of SDS since the solubility of the polymer is more in SDS and the polymer network is disturbed in presence of SDS, which results in the increase in surface area of the polymer films. In the presence of dipeptide and tripeptide, the surface area of the polymer film decreased with a slight increase in the surface pressure indicating the binding of these peptides to polymer, which enhances the stability of the polymer film. Thermodynamic studies on the change in surface area (ΔA) and excess free energy of mixing (ΔG(mix)(E)) associated with the formation of the mixed film suggest the occurrence of a thermodynamically unstable mixed film. The presence of SDS slightly decreases the formation of mixed film of stearic acid with triblock copolymer and peptides due to the solubilization of these compounds in SDS. However, the hydrophobicity of the polymer films increases in the presence of stearic acid, leading to the increase in surface pressure. The positive deviation of ΔA and the positive ΔG(mix)(E) values show the non-ideality and incompatibility of thermodynamically unstable mixed films. The thermodynamic results suggest that the stability and compatibility of the polymer, peptides and their mixed films with stearic acid in the presence of SDS are decreased, which is in good agreement with the results obtained for other polymeric systems.     

Influence of Foam Apparent Viscosity and Viscoelasticity of Liquid Films on Foam Stability

The objective of this research work was to study the relationship among the apparent viscosity of bulk foam, the viscoelasticity of liquid films, and foam stability. Bulk foam tests showed that the drainage half-life of AOS foam was higher than that of sodium dodecyl sulfate (SDS) and hexadecyltrimethyl ammonium bromide (CTAB) foams. The results of foam apparent viscosity revealed that the foam apparent viscosity was related to foam quality rather than foam stability. Higher film viscoelasticity modulus could be assigned for α -olefin sulfonate (AOS) films than those for SDS and CTAB ones. The film conductivity tests indicated that AOS liquid films, compared with SDS and CTAB liquid films, could delay the liquid drainage speed under dynamic conditions. Compared with foam apparent viscosity, the viscoelasticity of liquid films appeared to be a key factor in foam stability.     

Surfactant-assisted electrodeposition and improved electrochemical capacitance of silver-doped manganese oxide pseudocapacitor electrodes

Ag-doped MnO₂ pseudocapacitor electrodes with dendrite and foam-like structures were successfully produced for the first time using an electrodeposition method employing structure-directing agents, i.e., sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB) acting through micelle formation at solid–liquid interfaces. Doping silver with MnO₂ enhanced their electronic conductance. Controlling pseudocapacitor electrode morphologies with surfactants accelerated ion transport. The specific capacitance values of the Ag-doped MnO₂ films produced with SDS and CTAB, measured in 0.5?M Na₂SO₄ at a scan rate of 5?mV?s^?1 were 551 and 557?F?g^?1, respectively. These values are about 2.7-fold higher than that of the pure MnO₂ film and about 1.4-fold higher than that of the Ag-doped MnO₂ film made without using surfactants.     

Growth of crystalline rubrene films with enhanced stability

The growth of well-oriented crystalline films of rubrene (C42H28) on SiO2 and Au111 substrates is achieved by employing "hot wall" deposition whereas organic molecular beam deposition (OMBD) only yields rather amorphous layers or poly-crystalline dendritic networks at elevated temperature. This pronounced difference in film growth is related to the conformational change of rubrene molecules involving a loss of chirality upon crystallization and the enhanced diffusion which becomes possible at high temperature and large vapor pressure. Moreover, it is demonstrated that the crystalline rubrene films reveal an enhanced thermal and chemical stability as compared to the OMBD grown films.     

Thermo-responsive Hercosett/Poly(N-isopropylacrylamide) films: a new, fast, optically responsive coating

Poly(N-isopropylacrylamide) (PNIPAM) is a common thermo-responsive, water-soluble polymer, while Hercosett is a cationic resin commonly employed in the paper industry. In this paper, Hercosett? and poly(N-isopropylacrylamide) (PNIPAM) nanoparticles were used to prepare composite films that show thermo-responsive behavior and swelling–shrinking properties in water. First, size-controlled PNIPAM hydrogel nanoparticles were synthesized. These were then embedded within a matrix of the cationic resin Kymene 577H by film casting. The distribution of nanoparticles in the resin film was investigated. The thermo-responsive properties of the as-synthesized PNIPAM hydrogel nanoparticles and of the composite films were characterized together with the repeatability of the swelling–shrinking cycles. The presence of nanoparticles endowed the film with highly enhanced water retention (in comparison with resin-only films) and, most importantly, thermo-responsiveness. A very fast optical and morphological response was in fact observed. Due to the dual (optical and morphological) response, this new system is suitable for applications in optical or morphological actuation and gating.     

Surfactant exudation in the presence of a coalescing aid in latex films studied by atomic force microscopy1

We report atomic force microscopy images of surfactant (SDS) exudation in PBMA latex films, in the presence and the absence of a coalescing aid (Texanol^?, TPM). The exudates appear as hilly islets, and at times as mountains, at the film surface. Their size and number increase upon annealing above the glass-transition temperature of the latex polymer. TPM was found to be a strong promoter of surfactant exudation at the air-polymer interface. In the absence of TPM, annealing the films for several hours at 70°C led to very little migration of surfactant to the surface at most sites in the film. When the films with structures of SDS on their surface were immersed in water, these structures disappeared. Pores, ranging in size from tens to hundreds of nm in diameter, were clearly visible in the surface of the films. These films dry from the edges of the film inward, with a propagation front concentrating the water-soluble species into a turbid, moist region in the center. At this site, the rate at which the surfactant comes to the surface is enormously enhanced over that at other sites in the film. This is likely due to the high concentration of surfactant in this region, transported there by the drying process. © 1995 John Wiley & Sons, Inc.     

Molecular Orientation and Structural Characterization of Ultrathin Films of C12AzoNaph(1,4)C6N-SDS Studied by FT-IR and NIR-SERS Spectroscopies

IntroductionAzobenzene- containing long- chain fatty acidsand their ammonium amphiphiles have recentlyaroused a great interest of some researchersbecause of their promising photochromicproperties[1— 6 ] . In order to understand theinteresting physical properties the LB films withazo chromophores show,a structure- functionrelationship of the films must be explored.Thusfar,infrared spectroscopy has been usedextensively for the investigations of molecularaggregation,orientation and structuralch…     

Second harmonic generation from insoluble films of a rhodamine dye at the air-water interface: effect of sodium dodecylsulfate

The second harmonic generation (SHG) from the insoluble monolayers of bis-(N-ethyl, N-octadecyl)rhodamine perchlorate (RhC18) formed on the surface of sodium dodecylsulfate (SDS) solutions of different concentrations has been studied. An enhancement of the second harmonic response was observed in the mixed films of RhC18/SDS compared to the pure-dye layer. To clarify the origin of the phenomenon, the films were characterized by surface pressure-area isotherm and reflection-absorption spectroscopy studies. The analysis of surface pressure-area isotherms of RhC18/SDS layers showed that incorporated SDS molecules essentially influence the rheological properties of the dye monolayer. The film parameters, such as the molecular surface area, maximum surface pressure, and solid-condensed phase composition, are the functions of SDS bulk concentration. A joint analysis of the SHG results and the reflection-absorption spectra revealed that the structural ordering within films was responsible for the enhancement of the nonlinear optical response, whereas the contributions from the spectral shifts and increased absorption upon aggregate formation are of less importance.     

两步电泳沉积制备TiO2光阳极用于高效染料敏化太阳能电池

采用不同沉积电压制备TiO₂光阳极,研究电压对薄膜沉积速率、厚度和形貌的影响。通过台阶仪、光学照片、扫描电子显微镜(SEM)、电化学交流阻抗谱、开路电压衰减曲线对光阳极和电池进行系统表征,并测试了染料敏化太阳能电池器件的电流密度-电压(J-V)曲线,计算其光电转换效率。结果表明,提高沉积电压时,光阳极薄膜的沉积速率加快,膜厚也增加,但是电压过高时,薄膜会有裂缝和覆盖不全的问题,这会对电池的效率造成负面影响。综合考虑低沉积电压条件下薄膜均匀无裂缝和高沉积电压条件下沉积速率快的优点,采用先30 V电压、后60 V电压的电泳沉积方式来制备光阳极,结果呈现协同效果,既降低了制备时间又得到高质量的薄膜,在无其他修饰的情况下,电池的光电转换效率可以达到7.29%。     

两步电泳沉积制备TiO2光阳极用于高效染料敏化太阳能电池

采用不同沉积电压制备TiO₂光阳极,研究电压对薄膜沉积速率、厚度和形貌的影响。通过台阶仪、光学照片、扫描电子显微镜（SEM）、电化学交流阻抗谱、开路电压衰减曲线对光阳极和电池进行系统表征,并测试了染料敏化太阳能电池器件的电流密度-电压（J-V）曲线,计算其光电转换效率。结果表明,提高沉积电压时,光阳极薄膜的沉积速率加快,膜厚也增加,但是电压过高时,薄膜会有裂缝和覆盖不全的问题,这会对电池的效率造成负面影响。综合考虑低沉积电压条件下薄膜均匀无裂缝和高沉积电压条件下沉积速率快的优点,采用先30 V电压、后60 V电压的电泳沉积方式来制备光阳极,结果呈现协同效果,既降低了制备时间又得到高质量的薄膜,在无其他修饰的情况下,电池的光电转换效率可以达到7.29%。     

Sodium Dodecyl Sulfate Doped Polyaniline for Enhancing the Electrochemical Sensitivity of Mercury Ions

Polyaniline (PANi) was electro‐synthesized on the surface of screen‐printed carbon electrodes in the presence of sodium dodecyl sulfate (SDS) as a dopant. The complex of aniline and SDS created a conductive (PANi‐SDS) film at lower aniline concentration. The PANi‐SDS film contained negative charge due to the anionic head of SDS. The PANi‐SDS modified electrode was integrated into a poly(dimethylsiloxane) microfluidic chip as an electrochemical sensor for mercury detection. The presence of SDS in the polyaniline film enhanced the possibility of mercury ions uptake, and therefore, increased the peak current of square wave anodic stripping in the mercury detection. The mercury sensor exhibited a dynamic range from 6 to 35 nM with detection limit of 2.4 nM.