Wetting Of Ion Containg Polymers: Micelles Versus Molecular Absorption

1998 ◽  
Vol 543 ◽  
Author(s):  
T. A. Hill ◽  
X. Jiao ◽  
C. W. Martin ◽  
D. D. Demarteau ◽  
D. Perahia
Keyword(s):  
Surface Tension ◽  
Light Scattering ◽  
Chemical Composition ◽  
Surface Structure ◽  
Polymer Surface ◽  
Neutron Reflectivity ◽  
Molecular Absorption ◽  
Wetting Behavior ◽  
Wetting Properties ◽  
Carbon Backbone

AbstractThe wetting behavior of perfluorinated ionomers has been investigated as a function of polymer-surface interaction, the nature of the counter-ion and the structure of the polymer in the solvent from which it has been cast onto the surface. Two different ion-containing polymers, with a per-fluoro-carbon backbone were studied. They differ in the chemical composition and the polarity of their side chains. AFM results together with neutron reflectivity, light scattering and surface tension measurements had shown that the structure of the polymer in the parent solution has a profound effect on the wetting properties as well as the surface structure of the polymers.

Thin Conducting Polymer Films: Effect of Thickness on Wetting Behavior of Polyaniline Ultra Thin Films

1998 ◽  
Vol 543 ◽  
Author(s):  
J. Li ◽  
T. H. Hill ◽  
R. V. Gregory ◽  
D. Perahial
Keyword(s):  
Thin Films ◽  
Surface Structure ◽  
Oxidation State ◽  
Neutron Reflectivity ◽  
Wetting Properties ◽  
Thin Region ◽  
Spherical Domains ◽  
Molecular Layers ◽  
Conducting Polymer Films ◽  
Polymer Thickness

AbstractWetting properties and surface structure of polyaniline (PANI) thin films were studied as a function of the polymer thickness, using AFM and neutron reflectivity. Increasing the oxidation state as well as polymer thickness was found to increase the tendency of the polymer to form polycrystalline films. Three main regions with characteristic behavior were observed: ultra thin films of the order of several molecular layers, an intermediate thickness film of several molecular layers to ∼150nm, and films thicker than 150nm. In the ultra thin region the polymer formed nano-scale spherical domains. In the intermediate one, the films tend to be continuous and amorphous. In the thick films, crystallinity was observed.

scholarly journals Adsorption versus aggregation of NIPAM nanogels: new insight into their behaviour at the air/water interface as a function of concentration

2017 ◽  
Vol 19 (26) ◽  
pp. 17173-17179 ◽  
Author(s):  
Katarzyna Zielińska ◽  
Richard A. Campbell ◽  
Ali Zarbakhsh ◽  
Marina Resmini
Keyword(s):  
Surface Tension ◽  
Light Scattering ◽  
Dynamic Light Scattering ◽  
Neutron Reflectivity ◽  
Water Interface ◽  
Adsorption Behaviour ◽  
Air Water Interface ◽  
Insight Into

We have used neutron reflectivity (NR) measurements in combination with dynamic light scattering (DLS), surface tension and ellipsometry, to study the adsorption behaviour at the air/water interface of N-isopropylacrylamide-based nanogels as a function of concentration.

Preparation of graft copolymers by the reaction of polymeric acyl chlorides with monohydroxy-terminated polymers: An introductory study

1988 ◽  
Vol 53 (8) ◽  
pp. 1735-1744 ◽  
Author(s):  
Jitka Horská ◽  
Jaroslav Stejskal ◽  
Pavel Kratochvíl ◽  
Aubrey D. Jenkins ◽  
Eugenia Tsartolia ◽  
...  
Keyword(s):  
Light Scattering ◽  
Chemical Composition ◽  
Statistical Model ◽  
Graft Copolymers ◽  
Coupling Reaction ◽  
Molecular Characteristics ◽  
Gel Formation ◽  
Acyl Chlorides ◽  
Molecular Weights

An attempt was made to prepare well-defined graft copolymers by the coupling reaction between acyl chloride groups located along the backbone chain and monohydroxy-terminated grafts prepared separately. The molecular weights and the parameters of heterogeneity in chemical composition of the products were determined by light scattering and osmometry. The determination of molecular characteristics revealed that the degree of grafting was low. The results therefore could not be confronted with a statistical model at this stage. The problems encountered in the synthesis, e.g., gel formation, and the data relating to the soluble products are discussed.

Investigation of material flow on inscribing a polymer surface grating probing X-ray and VIS light scattering

2002 ◽  
Vol 198-200 ◽  
pp. 107-111 ◽  
Author(s):  
O Henneberg ◽  
Th Geue ◽  
M Saphiannikova ◽  
U Pietsch ◽  
A Natansohn ◽  
...  
Keyword(s):  
Light Scattering ◽  
Material Flow ◽  
Polymer Surface ◽  
X Ray ◽  
Surface Grating

Aerosol chemical composition and light scattering during a winter season in Beijing

2015 ◽  
Vol 110 ◽  
pp. 36-44 ◽  
Author(s):  
Jun Tao ◽  
Leiming Zhang ◽  
Jian Gao ◽  
Han Wang ◽  
Faihe Chai ◽  
...  
Keyword(s):  
Light Scattering ◽  
Chemical Composition ◽  
Winter Season ◽  
Aerosol Chemical Composition

scholarly journals Neutron reflectivity and surface tension measurements of a diblock copolymer monolayer on a selective solvent

1993 ◽  
Vol 03 (C8) ◽  
pp. C8-49-C8-52 ◽  
Author(s):  
M. S. KENT ◽  
L. T. LEE ◽  
B. J. FACTOR ◽  
F. RONDELEZ ◽  
G. SMITH
Keyword(s):  
Surface Tension ◽  
Diblock Copolymer ◽  
Neutron Reflectivity ◽  
Selective Solvent

scholarly journals On the contribution of Aitken mode particles to cloud droplet populations at continental background areas – a parametric sensitivity study

2007 ◽  
Vol 7 (3) ◽  
pp. 6077-6112
Author(s):  
T. Anttila ◽  
V.-M. Kerminen
Keyword(s):  
Surface Tension ◽  
Particle Size ◽  
Chemical Composition ◽  
Pure Water ◽  
Particle Surface ◽  
Chemical Properties ◽  
Sensitivity Study ◽  
Geometric Standard Deviation ◽  
Cloud Droplets ◽  
Aitken Mode

Abstract. Aitken mode particles are potentially an important source of cloud droplets in continental background areas. In order to find out which physico-chemical properties of Aitken mode particles are most important regarding their cloud-nucleating ability, we applied a global sensitivity method to an adiabatic air parcel model simulating the number of cloud droplets formed on Aitken mode particles, CD2. The technique propagates uncertainties in the parameters describing the properties of Aitken mode to CD2. The results show that if the Aitken mode particles do not contain molecules that are able to reduce the particle surface tension more than 30% and/or decrease the mass accommodation coefficient of water, α, below 10−2, the chemical composition and modal properties may have roughly an equal importance at low updraft velocities characterized by maximum supersaturations <0.1%. For larger updraft velocities, however, the particle size distribution is clearly more important than the chemical composition. In general, CD2 exhibits largest sensitivity to the particle number concentration, followed by the particle size. Also the shape of the particle mode, characterized by the geometric standard deviation (GSD), can be as important as the mode mean size at low updraft velocities. Finally, the performed sensitivity analysis revealed also that the chemistry may dominate the total sensitivity of CD2 to the considered parameters if: 1) the value of α varies at least one order of magnitude more than what is expected for pure water surfaces (10−2–1), or 2) the particle surface tension varies more than roughly 30% under conditions close to reaching supersaturation.

scholarly journals PECULARITIES OF MICELLE FORMATION OF PENTACYCLIC GLYCOSIDES IN AQUEOUS SOLUTIONS

2021 ◽  
Vol 64 (4) ◽  
pp. 26-33
Author(s):  
Natalia V. Mironenko ◽  
Irina V. Shkutina ◽  
Vladimir F. Selemenev
Keyword(s):  
Surface Tension ◽  
Light Scattering ◽  
Dynamic Light Scattering ◽  
Aqueous Solutions ◽  
Hydrodynamic Radius ◽  
Critical Concentration ◽  
Micelle Formation ◽  
Cylindrical Shape ◽  
Scattering Method ◽  
Dynamic Light Scattering Method

The regularities of changes in structural characteristics during the formation of associates in micellar aqueous solutions of triterpene saponins Quillaja Saponin and Sapindus Mukorossi are considered. The dependence of surface tension and adsorption on the concentration of an aqueous saponin solution is analyzed, and the values of surface activity and parameters of the adsorption layer are calculated. The average values of diffusion coefficients for spherical and cylindrical micelles are determined based on the measurement of the solution viscosity. The effect of the electrolyte solution on the surface tension and viscosity of glycoside solutions is studied: when the electrolyte is introduced into the saponin solution, the surface tension decreases, which leads to a shift in the critical concentration of micelle formation towards lower concentrations. The introduction of potassium chloride electrolyte reduces the degree of ionization and, as a result of suppressing the electroviscosity effect, leads to a decrease in the viscosity of the solution. The dynamic light scattering method is used to determine the size of glycoside aggregates. It is established that there are aggregates of several sizes in an aqueous solution of saponin. The size and shape of aggregates were calculated using the concepts of micelle packing parameters. In the region of very low concentrations of glycoside solutions, when approaching the critical concentration of micelle formation in the solution, there are spherical micelles. A further increase in the saponin concentration in the solution leads to a decrease in the content of structures with a hydrodynamic radius of 50-80 nm and the appearance of larger agglomerates with sizes greater than 100 nm. It was found that micelles acquire a less hydrated and more densely packed cylindrical shape in the concentration range of 1.7-2.6 mmol/dm3. Compaction of associates leads to an increase in the content of particles with a hydrodynamic radius of 150-250 nm and larger ones, and their presence predicts the appearance of larger agglomerates. Analyzing the data obtained using the dynamic light scattering method, it can be concluded that aggregates of several sizes co-exist in the volume of aqueous saponin solutions at certain concentrations.

scholarly journals Controlled Surface Wettability by Plasma Polymer Surface Modification

Surfaces ◽  
2019 ◽  
Vol 2 (2) ◽  
pp. 349-371 ◽  
Author(s):  
Muzammil Iqbal ◽  
Duy Khoe Dinh ◽  
Qasim Abbas ◽  
Muhammad Imran ◽  
Harse Sattar ◽  
...  
Keyword(s):  
Surface Modification ◽  
Surface Chemistry ◽  
Plasma Polymerization ◽  
Polymer Surface ◽  
Real Life ◽  
Polymer Coatings ◽  
Surface Wettability ◽  
Smart Polymer ◽  
Wetting Behavior ◽  
Polymer Surface Modification

Inspired by nature, tunable wettability has attracted a lot of attention in both academia and industry. Various methods of polymer surface tailoring have been studied to control the changes in wetting behavior. Polymers with a precisely controlled wetting behavior in a specific environment are blessed with a wealth of opportunities and potential applications exploitable in biomaterial engineering. Controlled wetting behavior can be obtained by combining surface chemistry and morphology. Plasma assisted polymer surface modification technique has played a significant part to control surface chemistry and morphology, thus improving the surface wetting properties of polymers in many applications. This review focuses on plasma polymerization and investigations regarding surface chemistry, surface wettability and coating kinetics, as well as coating stability. We begin with a brief overview of plasma polymerization; this includes growth mechanisms of plasma polymerization and influence of plasma parameters. Next, surface wettability and theoretical background structures and chemistry of superhydrophobic and superhydrophilic surfaces are discussed. In this review, a summary is made of recent work on tunable wettability by tailoring surface chemistry with physical appearance (i.e. substrate texture). The formation of smart polymer coatings, which adjust their surface wettability according to outside environment, including, pH, light, electric field and temperature, is also discussed. Finally, the applications of tunable wettability and pH responsiveness of polymer coatings in real life are addressed. This review should be of interest to plasma surface science communality particularly focused controlled wettability of smart polymer surfaces.

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