In a research lab, Mr. Z trying to formulate a colloidal dispersion system with sodium lauryl sulphate. What type of colloidal system is suitable for sodium laurly sulphate and also we have to discuss the different stability factors for sodium laurly sulphate dispersion.
1.2 Solution to the question:
Introduction of colloids: Colloids are homogeneous non-crystalline substances. Here one substance is divide into more minute particles called colloidal particles and then it dispersed through a second particle. It includes emulsions, gel, sol. Colloids helpful for arising the problems in the preparation and dispersion of emulsions, suspensions, ointments, powders and other compresses dosage forms. In this the disperse system …show more content…
They are lyophilic, lyophobic and association colloids.
Type of colloidal system:
Type of colloidal system is suitable for sodium lauryl sulphate is association colloidal system. They are three types of colloidal system, in that association or amphiphilic is the third type of colloidal system. Association colloids are micro heterogeneous system, here the particles of the colloidal dispersed phase formed agglomeration of molecules or ions of the substance dissolved in the dispersion medium. Amphiphile or surface active agents are characterized by two distinct region of opposing affinities with the same molecule or ion. When the liquid medium present at low concentration, the amphiphiles exist separately and the size to be subcolloidal. As a concentration increased the aggregation occurs over the narrow concentration range. These aggregates contain 50 or more monomers are called micelles. The concentration of monomer at which micelles form is called as critical micelle concentration (CMC). Below the cmc, the concentration of amphiphile undergo absorption by increasing air-water interface as the total amphiphile is raised. It reached some point the interface and bulk phase become saturated with monomers, this is nothing but cmc. To form micelle in the bulk phase, we will add …show more content…
We cannot addresses directly sedimentation / floating problem by electrostatic and steric stabilization. Particle sedimentation occurs from different density of dispersed phase and the dispersion medium. Higher difference in densities faster the settling of particles. The gel network stabilization represents the principle to produce colloids are stable in both aggregation and sedimentation. Polymer is added to the colloidal suspension to form a gel network and it is characterized by shear thinning properties. Example, guar gum and xanthan. Particle settling decreases the stiffness of the polymeric matrix, where the particles are trapped. Polymeric chain provide electrostatic or steric stabilization to disperse the particles. Rheological shear thinning properties fine some beneficial in the preparation of suspension and their uses. As viscosity reduces at high shear rate facilities deagglomeration, mixing and flow of