Related Experiment Video
Updated: Jun 23, 2026
09:26
Synthesis and Characterization of Supramolecular Colloids
Published on: April 22, 2016
Consolidation of charged colloids during drying
Arijit Sarkar1, Mahesh S Tirumkudulu
1Department of Chemical Engineering, Indian Institute of Technology-Bombay, Powai, Mumbai 400076, India.
Langmuir : the ACS Journal of Surfaces and Colloids
|April 29, 2009
Summary
Surface charge significantly impacts latex particle consolidation during drying. An induced electric field enhances particle diffusivity, influencing the drying front and concentration profiles in colloidal dispersions.
Area of Science:
- Colloid and Surface Science
- Materials Science
- Physical Chemistry
Background:
- Colloidal particle consolidation is governed by factors like particle size, shape, and interparticle forces.
- Charged colloidal systems exhibit unique behaviors due to electrostatic interactions and ion dynamics.
Purpose of the Study:
- To investigate the specific influence of surface charge on the consolidation process during the drying of latex dispersions.
- To develop and validate a model for charged particle consolidation considering induced electric fields.
Main Methods:
- Experimental observation of particle concentration profiles during drying using fluorescence and bright-field microscopy.
- Development of a theoretical model incorporating an induced external electric field for charged particle consolidation.
Main Results:
- Experimental data confirmed that surface charge affects the consolidation front.
- The model predicted enhanced particle diffusivity at low concentrations due to the induced electric field.
- Measured concentration profiles aligned with model predictions, validating the charge effect.
Conclusions:
- Surface charge plays a crucial role in the drying consolidation of latex dispersions.
- The presence of an induced electric field in charged colloidal systems enhances particle diffusivity.
- The developed model accurately captures the influence of surface charge on consolidation dynamics.
Related Concept Videos
01:09Colloidal precipitates
The high insolubility of some precipitates can result in an unfavorable relative supersaturation. This can lead to colloidal particles with a large surface-to-mass ratio, where adsorption is promoted. For instance, in the precipitation of silver chloride, silver ions are adsorbed on the surface of the colloidal particles, forming a primary layer. This layer attracts ions of opposite charge (such as nitrate ions), forming a diffuse secondary layer of adsorbed ions. This electric double layer...
01:29The Colloidal State
The formation of a colloidal system is exemplified by an aqueous solution containing Cl− ions is introduced to another containing Ag+ ions, resulting in the precipitation of solid AgCl as extremely tiny crystals. Instead of settling out as a filterable precipitate, these crystals remain suspended in the liquid, showcasing a colloidal system.A colloidal system involves colloidal particles within the approximate range of 1 to 1000 nm in at least one dimension, dispersed in a medium called the...
01:06Coagulation
Colloidal solids are solid particles suspended in solution. They are usually negatively charged, attracting a compact primary layer of positively charged ions, which attract more counterions to form an electrical double layer. Electrostatic repulsion between the charged double layers prevents the particles from colliding, stabilizing the colloids. These solids are often undesirable because they can contain toxins that are difficult to remove. Coagulation is a technique that helps aggregate and...
03:22Colloids
Children at play often make suspensions such as mixtures of mud and water, flour and water, or a suspension of solid pigments in water known as tempera paint. These suspensions are heterogeneous mixtures composed of relatively large particles that are visible to the naked eye or can be seen with a magnifying glass. They are cloudy, and the suspended particles settle out after mixing. On the other hand, a solution is a homogeneous mixture in which no settling occurs and in which the dissolved...
00:52Washing, Drying, and Ignition of Precipitates
After filtration, the precipitate is washed to remove coprecipitated impurities and any remaining mother liquor. Colloidal precipitates, such as silver chloride, are washed with an electrolyte (such as dilute nitric acid) to prevent the peptization of the precipitate. In the case of slightly soluble precipitates, the wash solution contains a common ion to reduce solubility. Lead sulfate, which is slightly soluble in water, is washed with dilute sulfuric acid. Similarly, wash solutions may be...
01:17Colloids and Suspensions
Children at play often make suspensions such as mixtures of mud and water, flour and water, or a suspension of solid pigments in water known as tempera paint. These suspensions are heterogeneous mixtures composed of relatively large particles visible to the naked eye or seen with a magnifying glass. They are cloudy, and the suspended particles settle out after mixing. The suspended particles in a suspension settle out after some time of mixing. The separation of particles from a suspension is...