"Lyophilic" is a term used to describe a type of colloidal mixture that is composed of a colloid that is strongly attracted to the liquid in which it is dispersed. Colloids are a type of mixture that are composed of very small particles of one material that have been distributed evenly throughout another. "Lyo" means solvent, and "phylic" means loving. Lyophilic colloids have a strong attraction between the colloidal particles and the liquid.
Creation of this mixture results in what is called lyophilic sol. In a lyophilic sol, the size of the dispersed particles is less than the size of particles in a suspension but larger than molecules in a solution. When the particles are dispersed in water, these colloids are called hyrdophilic colloids.
The term "lyophilic colloid" stems from the beginnings of the soap industry, when soap was created by boiling lye in vegetable oil. Lye was obtained from leaching wood ash with water. Boiling the lye in vegetable oil produced soap.
Lyophilics are formed from substances such as gum, starch and protein. Mixing the colloid with the liquid produces the sol. Lyophilic colloids that are dispersed through water are called hydrophilic colloids, and the dispersion created in this mixture is called a hydrophilic sol.
These types of colloids generally are stable and can be prepared by shaking the dispersion medium with the material to be dispersed. Gelatin and egg albumin are good examples of these types of lyophilics. Gum, proteins and rubber are other common examples of lyophilic colloids. It should be noted that these types of colloids are easily produced through simple means and generally are more stable than lyophobic colloids.
The study of colloidal science is not as developed as other areas of the scientific arena. There has been a tendency within scientific academia to avoid the study of colloidal science because it does not seem to fit within the defined boundaries of chemistry or physics. This was partly because of the complexity of the science.
Colloidal science is a very interdisciplinary course of study. It includes the study of lyophilic colloids and lyophobic colloids, which are characterized by a lack of attraction between the colloidal particles and the liquid. The study often works with materials of doubtful composition and calls into question the precision and subjective nature of analysis and interpretation of results.
Advances in the understanding of physics and chemistry have allowed colloidal research to progress at a faster pace. The understanding of these core scientific principles has allowed the formulation of coherent theories about the nature of the colloidal world. The study has progressed to include relatively simple descriptive information as well as complex theory of colloidal behavior and principles.