The Effects of Surfactants on the Morphology of Colloidal Crystals in Self-assembly

2006 ◽  
Vol 942 ◽  
Author(s):  
Zuocheng Zhou ◽  
Qin Li ◽  
Likui Wang ◽  
Xiusong Zhao
Keyword(s):  
Crystal Structure ◽  
Surface Tension ◽  
Contact Angle ◽  
Self Assembly ◽  
Colloidal Particles ◽  
Colloidal Suspension ◽  
Sodium Dodecyl ◽  
Colloidal Crystals ◽  
Phase Contact ◽  
Surfactant Solutions

AbstractIn this research, sodium dodecyl sulfates (SDS) and N-cetyl-n,n,n-trimethyammonium bromide (CTAB) surfactant solutions are used as solvents of polystyrene (PS) colloidal suspension during the fabrication of colloidal crystals. The effects of the surfactant on the quality and the morphology of the colloidal crystals are studied. It was found that surfactants not only change the charge of PS colloidal particles, but also significantly changed the surface tension and the 3 phase contact angle of the suspension with respect to the glass substrate, in turn they change the thickness of the formed crystal as well as the crystal structure. The derived knowledge will be potentially useful in clarifying the mechanisms involved in the formation of colloidal crystals.

scholarly journals Synthesis of magnetic mesoporous titania colloidal crystals through evaporation induced self-assembly in emulsion as effective and recyclable photocatalysts

2015 ◽  
Vol 17 (41) ◽  
pp. 27653-27657 ◽  
Author(s):  
Jeffrey E. Chen ◽  
Hong-Yuan Lian ◽  
Saikat Dutta ◽  
Saad M. Alshehri ◽  
Yusuke Yamauchi ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Magnetic Properties ◽  
Self Assembly ◽  
Colloidal Crystal ◽  
Colloidal Crystals ◽  
Mesoporous Titania ◽  
Evaporation Induced Self Assembly

This study illustrates the directed self-assembly of mesoporous TiO2 with magnetic properties due to its colloidal crystal structure with Fe3O4.

MODELING OF THE SURFACE TENSION OF COLLOIDAL SUSPENSIONS

2016 ◽  
Vol 24 (04) ◽  
pp. 1750050 ◽  
Author(s):  
ROGHAYEH HADIDIMASOULEH ◽  
MAZIAR SAHBA YAGHMAEE ◽  
REZA RIAHIFAR ◽  
BABAK RAISSI
Keyword(s):  
Surface Tension ◽  
Colloidal Particles ◽  
Colloidal Suspension ◽  
Colloidal Suspensions ◽  
Thermodynamic Relation ◽  
Fundamental Properties ◽  
Bubble Pressure ◽  
Air Water Interface ◽  
Numerous Experimental Data ◽  
Modified Equation

Surface tension is one of the fundamental properties of the colloids, which can be altered by concentration and size of colloidal particles. In the current work, modeling of the surface tension of suspension as it would be analyzed by maximum bubble pressure method has been performed. A new modified equation to correlate the surface tension with the bubble pressure is derived by applying fundamental thermodynamic relation considering the presence of particles in suspension and curvature of the interface between the particles and bubbles inside liquid. Moreover, the change of particles concentration in air–water interface due to capillary force is also considered. The predicted surface tension using the developed model has been verified by numerous experimental data with deviation less than 5% in most of cases. It was found that the calculated surface tension is altered by contact angle and particle radius as well as particle concentration. The obtained model may have potential application to predict the surface tension of colloidal suspension.

Fabrication of Colloidal Crystals on Different Patterned Silicon Substrates by Self-Assembly Method

2013 ◽  
Vol 850-851 ◽  
pp. 92-95
Author(s):  
Yong Wan ◽  
Zhong Yu Cai ◽  
Ming Hui Jia ◽  
Chao Li ◽  
Wan Qin Yang
Keyword(s):  
Self Assembly ◽  
Colloidal Suspension ◽  
Colloidal Crystals ◽  
The Self ◽  
Surface Pattern ◽  
Silicon Substrates ◽  
Assembly Process ◽  
Assembly Method ◽  
Microsphere Size ◽  
Influent Factors

Silica and polystyrene (PS) microspheres assembled on two quite different patterned silicon substrates, cross-like pillar pattern and eye-like pattern, respectively. The results indicated that the surface pattern imposes a predetermined lattice orientation in colloidal crystals (CCs). Other influent factors, such as microsphere size, the altitude of pattern and the concentration of colloidal suspension, may also play an important role on the self-assembly process.

scholarly journals Magnetic Field Effects on Aqueous Anionic and Cationic Surfactant Solutions Part II: Surface Tension

2019 ◽  
pp. 1-6
Author(s):  
Emil Chibowski ◽  
Aleksandra Szcześ ◽  
Lucyna Hołysz
Keyword(s):  
Magnetic Field ◽  
Surface Tension ◽  
Pure Water ◽  
Sodium Dodecyl ◽  
Magnetic Field Effects ◽  
Field Effects ◽  
Surfactant Solutions ◽  
Field Action ◽  
Acceleration Force ◽  
First Time

Magnetic Field (MF) effects on water and dispersed systems have been studied for more than half of century. However, so far there is no complete understanding of the observed changes in the properties of studied systems if it is solely based on the classical theories of magnetic field action. In Part I of this paper we presented results of MF influence on the evaporation rate of aqueous solutions of anionic surfactant Sodium Dodecyl Sulphate (SDS) and cationic one Dodecyl Trimethylammonium Bromide (DoTAB). In this paper static magnetic field effects on the surface tension of the above-mentioned surfactants are presented. The concentrations of the solutions used were both below and above their Critical Micelle Concentration (CMC). The solutions were under the MF action for 60 min in a closed vessel and were stirred by hand every 15 min. Previously it was found that the surface tension of pure water (distilled in a quartz apparatus) decreased by 2.1 mN/m after similar the MF treatment. Moreover, the memory effect lasted longer than 60 min. In case of the surfactant solutions the surface tension changed depending both on the kind of surfactant and its concentration. Bigger changes were observed for cationic DoTAB. In the solutions below their CMC the surface tension was lower after MF treatment. However, the surface tension of DoTAB solution at CMC increased several mN/m after the MF treatment. In the solutions concentrated above the CMC, respectively, the MF effects were practically vanishing. The observed changes are discussed in detail considering the structure of the surfactant adsorbed layers and acceleration force acting on the ions which was calculated from the Lorentz equation. To our knowledge, such results are published in the literature for the first time and they should be considered as preliminary ones. More systematic experiments are needed to better understand the observed changes.

Study of Influence Factors on Wettability of Coal Dust

2013 ◽  
Vol 724-725 ◽  
pp. 1050-1053
Author(s):  
Yin Yu Sun ◽  
Rong Chun Nie ◽  
Lin Lin Zhang
Keyword(s):  
Surface Tension ◽  
Contact Angle ◽  
Fourier Transform ◽  
Coal Dust ◽  
Sodium Dodecyl ◽  
Influence Factors ◽  
Sodium Dodecyl Benzene Sulfonate ◽  
Tween 80 ◽  
Benzene Sulfonate ◽  
Dodecyl Benzene Sulfonate

In this study, coal samples of experimental come from the raw coal of Wangfenggang and Qidong. Sodium dodecyl benzene sulfonate (SDBS), sodium dodecyl sulfate (SDS), water-reducing admixture NF and Tween-80 are choosed as surfactants. The influence factors on wettability of coal dust were characterized by contact angle meter, fourier transform infrared spectroscopy (FTIR) and surface tension experiment. The research shows that the effect of solution on wettability of coal dust is mainly depended on the surface structure of coal dust, type and concentration of solution.

Designed self-assembly of metamaterial split-ring colloidal particles in nematic liquid crystals

Soft Matter ◽  
2019 ◽  
Vol 15 (28) ◽  
pp. 5585-5595 ◽  
Author(s):  
Jure Aplinc ◽  
Anja Pusovnik ◽  
Miha Ravnik
Keyword(s):  
Liquid Crystals ◽  
Self Assembly ◽  
Colloidal Particles ◽  
Ring Resonator ◽  
Nematic Liquid Crystals ◽  
Colloidal Crystals ◽  
Split Ring Resonator ◽  
Split Ring ◽  
2D And 3D

We demonstrate stable 2D and 3D nematic colloidal crystals of split ring resonator particles relevant for soft optical metamaterial applications.

Colloidal Crystals from Surface-Tension-Assisted Self-Assembly: A Novel Matrix for Single-Molecule Experiments

Langmuir ◽  
2008 ◽  
Vol 24 (21) ◽  
pp. 12142-12149 ◽  
Author(s):  
Wen Cong Yeon ◽  
Balakrishnan Kannan ◽  
Thorsten Wohland ◽  
Vivian Ng
Keyword(s):  
Surface Tension ◽  
Single Molecule ◽  
Self Assembly ◽  
Colloidal Crystals

Self-assembly of anisotropic red blood cell (RBC)-like colloidal particles

Soft Matter ◽  
2018 ◽  
Vol 14 (39) ◽  
pp. 7954-7957 ◽  
Author(s):  
Liujun Song ◽  
Xiaolin Du ◽  
Li Zhong ◽  
Xinya Zhang ◽  
Zhengdong Cheng
Keyword(s):  
Blood Cell ◽  
Red Blood Cell ◽  
Self Assembly ◽  
Multilayer Structure ◽  
Colloidal Particles ◽  
Colloidal Crystals ◽  
Bragg Diffraction ◽  
Diffraction Phenomenon ◽  
Crystalline Array

The diagram shows a highly ordered periodic crystalline array, multilayer structure, Bragg diffraction phenomenon and well-patterned binary colloidal crystals, respectively.

scholarly journals Wetting Process and Adsorption Mechanism of Surfactant Solutions on Coal Dust Surface

2019 ◽  
Vol 2019 ◽  
pp. 1-9
Author(s):  
Xiaonan Wang ◽  
Shujie Yuan ◽  
Bingyou Jiang
Keyword(s):  
Surface Tension ◽  
Contact Angle ◽  
Anionic Surfactant ◽  
Adsorption Mechanism ◽  
Coal Dust ◽  
Spreading Coefficient ◽  
Surfactant Solutions ◽  
Wetting Process ◽  
Adhesion Work ◽  
Dust Surface

To determine the wetting process and wetting mechanism of different surfactant solutions on coal dust surface, four types of surfactants (anionic surfactant 1227, anionic surfactant AOS, amphoteric surfactant CAB-35, and nonionic surfactant CDEA) are selected to measure their surface tension and contact angle. Based on the data, the adhesion work, spreading coefficient, and immersion work of the surfactant solutions on a coal dust surface are calculated and their adsorption mechanism is discussed. The results show that the surface tension and contact angle of AOS and CDEA are lower and smaller, respectively, their calculated spreading coefficients are higher, and their adhesion work and immersion work are less than those of 1227 and CAB-35. This shows that the wettability of the AOS and CDEA solutions for a coal dust surface is more than that of 1227 and CAB-35, whereas their adhesion is lower than that of the latter. The spreading coefficient can be used as an index to determine the wettability. The wetting ability of the AOS and CDEA aqueous solutions for coal dust is stronger than that of 1227 and CAB-35 because of the different adsorption forms of the surfactant molecules on the surface of the coal dust. The tail hydrophobic group of the AOS and CDEA surfactant molecules orient to the surface of the coal dust, whereas the head hydrophilic group directs to the solution, being easier to wet. The results show that anionic and nonionic surfactant solutions can significantly improve the wettability of a coal dust surface, providing a theoretical basis for selecting suitable surfactants as water-spray additives to improve the dust suppression efficiency.

The interaction of a moving fluid/fluid interface with a flat plate

1995 ◽  
Vol 296 ◽  
pp. 325-351 ◽  
Author(s):  
J. Billingham ◽  
A. C. King
Keyword(s):  
Surface Tension ◽  
Contact Angle ◽  
Flat Plate ◽  
Contact Line ◽  
Large Time ◽  
Dynamic Contact Angle ◽  
Dynamic Contact ◽  
Phase Contact ◽  
Three Phase ◽  
Time Problem

A well-known technique for metering a multiphase flow is to use small probes that utilize some measurement principle to detect the presence of different phases surrounding their tips. In almost all cases of relevance to the oil industry, the flow around such local probes is inviscid and driven by surface tension, with negligible gravitational effects. In order to study the features of the flow around a local probe when it meets a droplet, we analyse a model problem: the interaction of an infinite, initially straight, interface between two inviscid fluids, advected in an initially uniform flow towards a semi-infinite thin flat plate oriented at 90° to the interface. This has enabled us to gain some insight into the factors that control the motion of a contact line over a solid surface, for a range of physical parameter values.The potential flows in the two fluids are coupled nonlinearly at the interface, where surface tension is balanced by a pressure difference. In addition, a dynamic contact angle boundary condition is imposed at the three-phase contact line, which moves along the plate. In order to determine how the interface deforms in such a flow, we consider the small- and large-time asymptotic limits of the solution. The small-time and linearized large-time problems are solved analytically, using Mellin transforms, whilst the general large-time problem is solved numerically, using a boundary integral method.The form of the dynamic contact angle as a function of contact line velocity is the most important factor in determining how an interface deforms as it meets and moves over the plate. Depending on this, the three-phase contact line may, at one extreme, hang up on the leading edge of the plate or, at the other extreme, move rapidly along the surface of the plate. At large times, the solution asymptotes to an interface configuration where the contact line moves at the far-field velocity.

Sign in / Sign up

Export Citation Format

Share Document