Poly(itaconates) monolayers behavior at the air/water interface. Study at different surface concentration

2004 ◽  
Vol 40 (10) ◽  
pp. 2349-2355 ◽  
Author(s):  
A. Leiva ◽  
L. Gargallo ◽  
A. González ◽  
D. Radic̀
Keyword(s):  
Surface Concentration ◽  
Water Interface ◽  
Air Water Interface ◽  
Interface Study

scholarly journals Adsorption Kinetics of a Cationic Surfactant Bearing a Two-Charged Head at the Air-Water Interface

Coatings ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 95 ◽  
Author(s):  
Marcos Fernández Leyes ◽  
Santiago Gimenez Reyes ◽  
Ezequiel Cuenca ◽  
Jhon F. Sánchez Morales ◽  
Hernán Ritacco
Keyword(s):  
Cationic Surfactant ◽  
Adsorption Process ◽  
Surface Concentration ◽  
Interfacial Region ◽  
Water Interface ◽  
Surface Tension Data ◽  
Time Resolved ◽  
Initial Stage ◽  
Wilhelmy Plate ◽  
Air Water Interface

We studied the dynamics of adsorption at the air-water interface of a cationic surfactant bearing two charges, Gemini 12-2-12, at concentrations below and above the critical micelle concentration (cmc). We used maximum bubble pressure and Wilhelmy plate techniques in order to access all time scales in the adsorption process. We found that the adsorption dynamics are controlled by diffusion at the initial stage of the adsorption process (milliseconds) and it is kinetically controlled by an electrostatic barrier (minute) approaching the equilibrium surfactant surface concentration. Between these two extremes, we found several relaxation phenomena, all following exponential decays with characteristic times spanning from one to hundreds of seconds. By means of time-resolved surface potential measurements, we show that these processes involve charge redistribution within the interfacial region. The surface tension data are analyzed and interpreted in the framework of the free energy approach.

Air/water interface study of cyclopentane-containing archaeal bipolar lipid analogues

2010 ◽  
Vol 163 (8) ◽  
pp. 794-799 ◽  
Author(s):  
Alicia Jacquemet ◽  
Véronique Vié ◽  
Loïc Lemiègre ◽  
Julie Barbeau ◽  
Thierry Benvegnu
Keyword(s):  
Water Interface ◽  
Air Water Interface ◽  
Interface Study

Polymers containing phtalimidoalkyl groups in the side chains. effect of the alkyl groups in monolayers at the airwater interface

e-Polymers ◽  
2012 ◽  
Vol 12 (1) ◽  
Author(s):  
Ligia Gargallo ◽  
Angel Leiva ◽  
Alvaro González ◽  
Luz Alegría ◽  
Claudia Sandoval ◽  
...  
Keyword(s):  
Surface Pressure ◽  
Scaling Laws ◽  
Surface Concentration ◽  
Water Interface ◽  
Static Elasticity ◽  
Alkyl Groups ◽  
Air Water Interface ◽  
Pressure Area ◽  
Methylene Groups ◽  
Total Surface Free Energy

AbstractSurface activity of poly(methacrylate)s containing phthalimidoalkyl groups was studied. Surface pressure-area isotherms ( -A) at the air-water interface were determined. These polymers form stable and condensed monolayers. The monolayers are more condensed and the limiting surface area A0 values decrease when the number of the methylene groups in the lateral chains increases. Surface pressure variation at the semidilute region of the monolayers was expressed in terms of the scaling laws as power function of the surface concentration. The static elasticity εo and the exponent of the excluded volume υ were determined. The hydrophobicity degree of polymers was estimated from the determination of the total surface free energy values by wettability measurements. Molecular dynamic simulation (MDS) was performed in order to explain the experimental behavior of polymers at the air-water interface.

Sampling and analysis of the air-water interface with SEM and EDS of microlayers

1989 ◽  
Vol 47 ◽  
pp. 1004-1005
Author(s):  
Randall W. Smith ◽  
John Dash
Keyword(s):  
Heavy Metals ◽  
Surface Microlayer ◽  
Surface Films ◽  
Water Interface ◽  
Physical Processes ◽  
Infrared Spectroscopic Analysis ◽  
Eds Analysis ◽  
Air Water Interface ◽  
Significant Area ◽  
Bulk Chemical

The structure of the air-water interface forms a boundary layer that involves biological ,chemical geological and physical processes in its formation. Freshwater and sea surface microlayers form at the air-water interface and include a diverse assemblage of organic matter, detritus, microorganisms, plankton and heavy metals. The sampling of microlayers and the examination of components is presently a significant area of study because of the input of anthropogenic materials and their accumulation at the air-water interface. The neustonic organisms present in this environment may be sensitive to the toxic components of these inputs. Hardy reports that over 20 different methods have been developed for sampling of microlayers, primarily for bulk chemical analysis. We report here the examination of microlayer films for the documentation of structure and composition.Baier and Gucinski reported the use of Langmuir-Blogett films obtained on germanium prisms for infrared spectroscopic analysis (IR-ATR) of components. The sampling of microlayers has been done by collecting fi1ms on glass plates and teflon drums, We found that microlayers could be collected on 11 mm glass cover slips by pulling a Langmuir-Blogett film from a surface microlayer. Comparative collections were made on methylcel1ulose filter pads. The films could be air-dried or preserved in Lugol's Iodine Several slicks or surface films were sampled in September, 1987 in Chesapeake Bay, Maryland and in August, 1988 in Sequim Bay, Washington, For glass coverslips the films were air-dried, mounted on SEM pegs, ringed with colloidal silver, and sputter coated with Au-Pd, The Langmuir-Blogett film technique maintained the structure of the microlayer intact for examination, SEM observation and EDS analysis were then used to determine organisms and relative concentrations of heavy metals, using a Link AN 10000 EDS system with an ISI SS40 SEM unit. Typical heavy microlayer films are shown in Figure 3.

Temperature Dependence of the Air/Water Interface Revealed by Polarization Sensitive Sum-Frequency Generation Spectroscopy

2018 ◽  
Author(s):  
Daniel R. Moberg ◽  
Shelby C. Straight ◽  
Francesco Paesani
Keyword(s):  
Temperature Dependence ◽  
Low Frequency ◽  
Potential Energy Function ◽  
Md Simulations ◽  
Sum Frequency Generation ◽  
Water Molecules ◽  
Water Interface ◽  
Sum Frequency ◽  
Air Water Interface ◽  
Frequency Generation

<div> <div> <div> <p>The temperature dependence of the vibrational sum-frequency generation (vSFG) spectra of the the air/water interface is investigated using many-body molecular dynamics (MB-MD) simulations performed with the MB-pol potential energy function. The total vSFG spectra calculated for different polarization combinations are then analyzed in terms of molecular auto-correlation and cross-correlation contributions. To provide molecular-level insights into interfacial hydrogen-bonding topologies, which give rise to specific spectroscopic features, the vSFG spectra are further investigated by separating contributions associated with water molecules donating 0, 1, or 2 hydrogen bonds to neighboring water molecules. This analysis suggests that the low frequency shoulder of the free OH peak which appears at ∼3600 cm−1 is primarily due to intermolecular couplings between both singly and doubly hydrogen-bonded molecules. </p> </div> </div> </div>

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