Effect of thermo-physical properties of Zn precursors on ZnO thin films grown by ultrasonic spray

In the present work we have investigated temperature and precursor solution concentration influences on the density, viscosity and surface tension of zinc aqueous solutions. Three zinc salt solution sources, namely acetate, nitrate and chloride, have been investigated. The study was carried out at different concentrations ranged from 0.02 to 0.20 mol/l and solution temperatures varied from 20 to 60 °C. The measurements results show, for the whole studied salt sources, a linear increase in density, surface tension and viscosity with salt concentration. While an inverse behavior of these properties is observed with increasing solution temperature. Zinc acetate has the lower surface tension and viscosity, while zinc chloride has the largest ones. Droplets Weber, Reynolds numbers and surface enthalpy formation have been estimated from solution properties measurements. Ultimately a correlation between the used salts, concentrations and the obtained ZnO thin films morphologies and structures is addressed. Solution viscosity and surface tension are key parameters controlling the films growth and morphology. At fixed substrate temperature, films with smooth surface can be produced by reducing the surface tension and the viscosity of the starting solution.     

Intrinsic viscosity,rheological property,and oil displacement of hydrophobically associating fluorinated polyacrylamide

The surface‐active polymer (FPAM) was synthesized by free‐radical polymerization of acrylamide (AM), 2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid (AMPS) and N ‐dodecyl‐N ‐perfluoro octane sulfonyl acrylamide (AMPD), which was prior prepared by reacting dodecylamine, perfluoro‐1‐octanesulfonyl fluoride, and acryloyl chloride. Parameters affecting the intrinsic viscosity ([η]) and apparent viscosity (η) of FPAM, such as reaction temperature, AMPD concentration, AMPS concentration, monomer concentration, initiator concentration, and pH were examined. Apparent viscosity and interfacial tension (IFT) of FPAM solution were evaluated. Subsequently, temperature tolerance and shear tolerance were investigated by comparing with hydrolyzed polyacrylamide (HPAM), and results indicated that the FPAM displayed better performances than HPAM. FPAM can reduce the IFT between crude oil/water, and the IFT values are around at 2.91 and 3.9 mN m^?1 corresponding to FPAM and HPAM/FC‐118. The sandpack model oil displacement experiment showed that water flooding can further increase the oil recovery to 15.01% (FPAM), compared with 9.26% oil recovery for HPAM, and 10.99% oil recovery for HPAM/FC‐118. The glass micromodel techniques for studying enhanced oil recovery get a good result and provide a useful reference for understanding the displacement behaviors in polymer flood process. It could be concluded that the introduction of fluorinated groups in the polymer chain was helpful in enhancing the oil displacement efficiency. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44672.     

A novel twin-tailed hydrophobically associating copolymer: synthesis, characterization and solution properties

Novel twin-tailed hydrophobically associating copolymers (DDSPAM) were prepared by micellar copolymerization of acrylamide (AM) and sodium vinylsulfonate with N,N-didecyl-N-methyl-N-(4-vinylbenzyl)ammonium chloride in an aqueous solution. The structure and composition of DDSPAM were characterized by ¹H-NMR and elemental analysis. While the molecular weights of the copolymers were obtained via static light scattering, the hydrodynamic radius of aggregates was investigated using dynamic light scattering. The critical micellar concentration cmc and γ _cmc values of DDSPAM were measured using fluorescence and later correlated with the values obtained from surface tension measurements. In addition, the viscosity stability studies of DDSPAM and hydrolyzed polyacrylamide (HPAM) revealed that DDSPAM, with twin tails of hydrophobic groups, exhibited better salt tolerance as well as temperature resistance compared to HPAM.     

Role of polymer–salt–solvent interactions in the electrospinning of polyacrylonitrile/iron acetylacetonate

Electrospinning is a process of producing ultrafine fibers by overcoming the surface tension of a polymer solution with electrostatic force. In this study, iron acetylacetonate was added to a polyacrylonitrile solution, and the role of polymer–salt–solvent interactions in the electrospinning of the ultrafine fibers was investigated. The polymer–salt–solvent interactions were characterized by Fourier transform infrared spectroscopy; and the solution viscosity, conductivity and surface tension were measured in solutions with different salt concentrations. The formation of polymer–salt–solvent interactions increased the solution viscosity, conductivity, and surface tension values at low salt concentrations. At high concentrations, the solution viscosity and surface tension decreased, but the conductivity remained relatively constant. The polymer–salt–solvent interactions influenced the structures of the electrospun fibers by changing the balance among the solution viscosity, conductivity, and surface tension. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Flourescent probe and ESEM morphologies of a acrylamide‐based terpolymer in aqueous solution

The terpolymer (PASA) of acrylamide with butyl styrene and sodium 2‐acrylamido‐2‐methylpropane sulfonate was synthesized. The composition and molecular structure were characterized by elemental analysis, UV, FTIR, and ¹H NMR. The aggregation behaviors of PASA were studied by means of the fluorescent probe analysis and environmental scanning electron microscope (ESEM). The flourescent probe analysis indicates that the PASA molecules form excellent hydrophobically associating structures in pure water and with the increase in PASA concentration at low concentrations, the nonpolarity of hydrophobic microdomains and the degree of intermolecular hydrophobic association increase in aqueous and brine solution. ESEM measurements show that gigantic aggregates have been formed in the PASA aqueous solution at the polymer concentration of 0.05 g dL^?1, which is the critical association concentration of the polymer, and excellent solution properties of PASA are attributed to integrated network‐structures formed by PASA in aqueous solution, which are collapsed by the addition of salt, resulting in the decrease in apparent viscosity of PASA in brine solution. However, with the increase in the NaCl concentration or the PASA concentration, the number and size of aggregates increase, leading to the remarkable increase in the apparent viscosity of PASA in brine solution. These results are consistent with the AFM and viscosity study results. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103:277–286, 2007     

Dilute solution properties of poly(3-dimethyl acryloyloxyethyl ammonium propiolactone)

The aqueous solution properties of an ampholytic poly(3-dimethylacryloyloxyethyl ammonium propiolactone), poly(DMAEAPL), are examined in this study by measuring reduced viscosity, intrinsic viscosity, degree of binding and dynamic light scattering. This polyampholyte's intrinsic viscosity is related to the type and concentration of the salt added. The intrinsic viscosity behaviour for the polyampholyte resulting from the associations of the polymer chains is in contrast with cationic and anionic polyelectrolyte. The polyampholyte in high concentration of NaCl has a low degree of binding, indicating that the proton ion (H⁺) has difficulty in binding to the carboxylate group (COO⁻) at the polymer end. The carboxybetaine, DMAEAPL, has a higher degree of binding than the corresponding sulfobetaine, DMAPS. Dynamic light scattering measurements indicate that the poly(carboxybetaine) diffusion coefficients decrease and the chain dimensions increase with an increasing salt concentration. The models proposed in this study can account for the poly(DMAEAPL) solution viscometrics and the degree of binding. © 1997 Elsevier Science Ltd.     

Effect of platinum salt concentration on the electrospinning of polyacrylonitrile/platinum acetylacetonate solution

The preparation and characterization of electrospun polyacrylonitrile (PAN)/platinum(II) acetylacetonate composite nanofibers were investigated. The solution properties, such as viscosity, surface tension, and conductivity, of Pt‐acetylacetonate‐added PAN solutions in N,N‐dimethylformamide were measured, and their influences on the resulting fiber structure were also determined. At low Pt salt concentrations, the addition of Pt salt increased the fiber diameter but did not change the fiber diameter distribution. However, the fiber diameter decreased, and the fiber diameter distribution became broader when the Pt salt concentration went beyond a critical value. The structure of the electrospun fibers was determined by the formation of polymer–salt– solvent interactions, which changed the balance among the viscosity, surface tension, and conductivity of the solutions. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Low Cationic Proportion Ampholytic Polymer: Synthesis,Solution Properties and Interaction with Anionic Surfactant

Novel ampholytic terpolymer of N-vinylformamide (NVF), vinylamine (VAm) and sodium acrylate (NA) with low cationic proportion was obtained by hydrolyzing copolymer of NVF and NA (PNVFNA). Solution properties of the polymer were investigated by methods of turbidity and viscosity experiment. The effect of sodium dodecyl sulfate (SDS) on solution viscosity was also investigated. The results showed that the turbidity curves were bimodal, and pH 3.0 was determined as the isoelectric point (IEP). At high salt concentration, polyampholyte effect was noticeable at IEP in viscosity experiment. Although the proportion of VAm in polyampholyte was lower, the solution properties were influenced markedly in the presence of SDS. At IEP, the viscosity increased more rapidly as salt concentration increased when 10^-3 mol/L SDS contained in solution. A mechanism of SDS bound to positive sites on the collapsed globule surface was suggested.     

Synthesis, Surface, Thermodynamic Properties of Some Biodegradable Vanillin-Modified Polyoxyethylene Surfactants

Four water-soluble non-ionic ethoxylated surfactants based on vanillin were synthesized (VE₁₅, VE₂₀, VE₄₀, and VE₆₀). The chemical structures of these surfactants were confirmed using FT-IR and ¹H-NMR spectra. The molecular weights of the compounds were determined using viscosity measurements and gel permeation chromatography. Surface tension as a function of the concentration of the surfactant in aqueous solution was measured at 25, 40 and 55?°C. From these measurements, the critical micelle concentration (CMC), effectiveness (??_cmc), efficiency (pC₂₀), maximum surface (??_max) excess and minimum surface area (A _min), were calculated. The surface activity measurements showed their high tendency towards adsorption and micellization and their good surface tension reduction, and low interfacial tension. The emulsion stability measurements showed the applicability of these surfactants as emulsifying agents. The thermodynamic parameters of micellization (??G _mic, ??H _mic, ??S _mic) and adsorption (??G _ads, ??G _ads, ?S _ads) showed their tendency towards adsorption at the interfaces and also micellization in the bulk of their solutions. The biodegradability of the prepared surfactants was tested in river water using die-away method and showed their readily biodegradation in the open environment.     

Synthesis,Surface Activity and Aggregation Properties of Glucosamide‐Based Polysiloxanes

Three glucosamide‐based polysiloxanes (GAPS) surfactants were prepared by amidation of gluconolactone with amino functional polysiloxanes synthesized by polymerization. GAPS were characterized by FT‐IR, ¹H NMR and ¹³C NMR. Surface activity and aggregation behavior in aqueous solution were studied by surface tension measurements, dynamic light scattering and transmission electron microscopy. GAPS can reduce the surface tension of water to 24 mN m^?1 at concentration levels of 10^?4 g mL^?1 and self‐assemble in water at room temperature to form spherical micelles with average diameters ranging from 30 to 1000 nm. The micelle diameter increases with increasing degree of polymerization.     

Aqueous solution properties of poly[3-dimethyl (methacryloyloxyethyl) ammonium propane sulfonate]

The aqueous solution properties of an ampholytic poly[3-dimethyl (methacryloyloxyethyl) ammonium propane sulfonate] [poly(DMAPS)] are studied by measurements of cloud point determination, intrinsic viscosity, degree of binding, and ionic strength. The minimum salt concentration and intrinsic viscosity of this polyampholyte are related to the type and concentration of added salt. Both the polymeric and monomeric betaines in the presence of NaCl have the lower degree of binding, indicating that the proton ion (H⁺) is relatively difficult to bind the SO^?₃ at the end of sulfobetaine. An increase in ionic strength causes the pK_a to decrease at the half-neutralization point.     

Synthesis of Bis[<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>′-(alkylamideethyl)ethyl] Triethylenediamine Bromide Surfactants and Their Oilfield Application Investigation

Bis[N,N′-(alkylamideethyl)ethyl] triethylenediamine surfactants are quaternary ammonium salt Gemini surfactants with amide, which are synthesized from fatty acid (dodecanoic, hexadecanoic, tetradecanoic and octadecanoic) methyl esters, triethylene tetramine and ethyl bromide. The chemical structures of the prepared compounds were characterized by elemental analysis, FTIR and ¹H-NMR spectra, melting point and Krafft point. Several properties of the synthesized surfactants were studied including surface tension, critical micelle concentration, interfacial tension, emulsification power, salt effect, corrosion inhibition efficiency and biological activity. The results show that the surface activity, critical micelle concentration and interfacial activity are correlated to their chemical structures. The emulsification power measurements of these surfactants show their low emulsifying tendency towards Tazhong’s crude oil from Tarim Oilfield. The synthesized surfactants also exhibit high biocidal activity towards Gram-positive and Gram-negative bacteria and fungi. This activity increases with the increase of alkyl chain length. The corrosion measurement of these surfactants in acidic media with a weight loss technique show good protection of mild steel alloys against acidic environments. These properties suggest that the synthesized compounds have potential for application in the oilfield area.     

羧酸盐表面活性剂与两亲聚合物相互作用研究

根据黏度和表面张力的测定数据研究了羧酸盐表面活性剂(HF-E)与两亲聚合物的相互作用,结果表明,HF-E/两亲聚合物混合溶液的表观黏度随HF-E质量浓度的增加先升高后下降;两亲聚合物的质量浓度越大,HF-E/两亲聚合物混合溶液表面张力越高;随着水的矿化度的升高,HF-E/两亲聚合物混合溶液的表观黏度先略有增加,到一定值后反而降低,而表面张力则随矿化度的增加而降低;温度升高,HF-E/两亲聚合物混合溶液的表观黏度随之降低而其与大庆模拟油间的界面张力则升高。优化后的高黏度低界面张力二元体系配方为HF-E和两亲聚合物的质量浓度分别为3和1.5 g·L-1;此外,还加入质量浓度为1 g·L-1的烷基醇酰胺(NS)。     

Aqueous solution properties of poly(trimethyl acrylamido propyl ammonium iodide) [poly(TMAAI)]

The aqueous solution properties of a cationic poly(trimethyl acrylamido propyl ammonium iodide) [poly(TMAAI)] were studied by measurements of reduced viscosity, intrinsic viscosity, and flocculation test. The reduced viscosity and intrinsic viscosity of this cationic polyelectrolyte were related to the types and concentration of added salt. “Soft” salt anions were more easily bound on the quaternary ammonium (R₄N⁺) of poly(TMAAI) than those of “hard” salt anions. Halide anions are hard anions; consequently, hard cations were more easily attracted to halide anions for reducing the binding degree of halide anion on the quaternary ammonium group (R₄N⁺). Some salt ions were observed to strongly attract the quaternary ammonium of the cationic polymeric side chain for coagulation of the polymers. This effect would make the polymeric aqueous solution become turbid. The intrinsic viscosity behavior for cationic polyelectrolyte resulting from the electrostatic repulsive force of the polymer chain is contrasted with polyampholyte. A comparison of various flocculants as to the effect of flocculation was also studied. © 1994 John Wiley & Sons, Inc.     

Electrospun poly lactic acid (PLA) fibres: Effect of different solvent systems on fibre morphology and diameter

The selection of an appropriate non-hazardous solvent or solvent system is essential to determine the rheological properties and electrospinnability of the solution, the productivity, and the morphology of nanofibres. In this study, poly lactic acid (PLA) solutions were prepared in various pure solvents and binary-solvent systems to investigate the effect of different solution properties on nanofibre morphology and diameter. Viscosity, conductivity and surface tension of each solution were measured. Nanofibre morphology was observed by scanning electron microscopy (SEM). Of all the solvent systems used acetone/dimethylformamide gave the highest fibre productivity and finest defect-free nanofibres. Therefore this solvent system was studied in more detail, varying the solvent ratio. Also the polymer concentration in this solvent system was varied to investigate the effect on nanofibre morphology and solution properties. Morphological investigations were done in correlation with rheological measurements: beaded nanofibrous structures were collected from solutions with concentration around the critical chain entanglement concentration (C_e), while defect-free nanofibres were produced when the concentration was increased to about twice the entanglement concentration. Further investigation of the effect of the PLA concentration on the elastic (G′) and the plastic (G″) moduli showed a sudden increase of the elastic moduli (G′) at the critical chain entanglement concentration. The results showed that the solvent properties, boiling point, viscosity, conductivity and surface tension, have a significant effect on process productivity, morphology and diameter distribution of the PLA nanofibres.     

Polysulfobetaines and corresponding cationic polymers. IV. Synthesis and aqueous solution properties of cationic poly(MIQSDMAPM)

A cationic poly(methyl iodide quaternized styrene-dimethylaminopropylmaleimide) copolymer [poly(MIQSDMAPM)] was synthesized by imidizing styrene-maleic anhydride (SMA) copolymer. Its aqueous solution properties were studied by measurements of reduced viscosity, intrinsic viscosity, and a flocculation test. The reduced viscosity and intrinsic viscosity of this cationic polyelectrolyte were related to the types and concentration of the added salt. “Soft” salt anions were more easily bound to the quaternary ammonium cation (R₄N⁺) of poly(MIQSDMAPM) than “hard” salt anions. Halide anions are hard anions; consequently, hard cations were more easily atracted to halide anions, and reduced binding degree of halide anion on the quaternary ammonium group (R₄N⁺). Some salt ions were observed to strongly attract the quaternary ammonium group of the cationic polymeric side chain and resulted in agglomeration of the polymers. A comparison of various flocculants as to the effect of flocculation was made in this study. © 1996 John Wiley & Sons, Inc.     

Study on the morphology of the novel hydrophobically associative acrylamide‐based terpolymer in aqueous solution by AFM measurements

The synthesized hydrophobically associating water‐soluble polymer P(AM‐BST‐NaAMPS) (PASA) exhibits good viscosification properties in the aqueous and brine solution. To study the viscosifying mechanisms of the polymer in the aqueous solution and brine solution, atomic force microscope (AFM) was applied to observe the micromorphology of the polymer solution. The AFM measurements show that continuous network structures have been formed in the aqueous solution of 0.05 g dL^?1 PASA, and with the increase in PASA concentration, the network structures become much bigger and more condensed. The network structures of PASA are collapsed by the addition of salt, and tree‐like crystals are formed, leading to the decrease in the apparent viscosity of PASA solution. However, by increasing the NaCl concentration or the polymer concentration in the brine solution, the sizes of crystals increase. These results are consistent with the ESEM and viscosity study results. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3996–4002, 2006     

Polysulfobetaines and corresponding cationic polymers. VI. Synthesis and aqueous solution properties of cationic poly(methyl iodide quaternized acrylamide–N,N-dimethylaminopropylmaleimide copolymer) [poly(MIQADMAPM)]

The copolymer prepared by copolymerizing with acrylamide and maleic anhydride was imidized with N,N-dimethylaminopropylamine. The obtained acrylamide–N,N-dimethylaminopropylmaleimide (ADMAPM) copolymer was then reacted with methyl iodide to yield a poly(methyl iodide quaternized acrylamide–N,N-dimethylaminopropylmaleimide) copolymer [poly(MIQADMAPM)]. Its aqueous solution properties were studied by measurements of reduced viscosity, intrinsic viscosity, and flocculation test in this study. The reduced viscosity and intrinsic viscosity of this cationic polyelectrolyte were related to the types and concentration of the added salt. “Soft” salt anions were more easily bound to the quaternary ammonium cation (R₄N⁺) of poly(MIQADMAPM) than were “hard” salt anions. Halide anions are hard anions; consequently, hard cations were more easily attracted to halide anions and reduced the binding degree of halide anion on the quaternary ammonium group (R₄N⁺). The intrinsic viscosity behavior for cationic polyelectrolyte resulting from the electrostatic repulsive force of the polymer chain was contrasted with polyampholyte. The effect of various flocculants on flocculation in different pH values was accessed in this study. © 1996 John Wiley & Sons, Inc.     

十二烷基苯磺酸钠表面张力的研究

通过表面张力的测定,研究了浓度、温度对溶液表面张力的影响,同时考察无机盐浓度对溶液表面张力的影响.结果表明:十二烷基苯磺酸钠溶液表面张力随浓度的增加、温度的升高和无机盐浓度逐渐的增大而降低,最终确定其CMC值为1.47×10-3mol/L,由于键能和水合离子半径的原因,NaCl对十二烷基苯磺酸钠表面张力的影响明显于KCl.     

Aggregation Behavior of Task-Specific Acidic Ionic Liquid N-Methyl-2-Pyrrolidinium Dihydrogen Phosphate [NMP][H2PO4] in Aqueous and Aqueous Salt Solutions

The effect of alkali salt (NaCl, NaBr, and KCl) addition on aggregate formation of N-methyl-2-pyrrolidinium dihydrogen phosphate [NMP][H₂PO₄] ionic liquid in aqueous solution was determined using surface tension at 298.15K and conductance from 288.15 to 308.15K. The surface parameters such as critical aggregation concentration (CAC), adsorption efficiency, surface pressure, surface tension at CAC, minimum surface cover by a single molecule, and maximum area excess concentration were calculated from surface tension measurements with and without salts. The results show that [NMP][H₂PO₄] forms aggregates at lower concentrations and is more surface active than classical cationic surfactants.