Sol-gel is a process where solid materials are produced from small molecules. The process handles the transformation of monomers into a colloidal solution (the Sol) that acts as the forerunner for an integrated network (the Gel) of either discrete particles or network polymers. So the procedure has essentially 2 parts: the Sol (solution) and the Gel.
- Sol (solution): A colloidal suspension of monomers (tiny particles that can be linked with identical molecules to create a network or polymer) on a liquid medium (usually water or alcohol).
- Gel: A semisolid colloidal suspension of a solid, evenly mixed in a liquid which exhibits no flow when in the steady state. Its properties cover a wide range from soft and weak to hard and tough.
In a nutshell, the Sol undergoes a hydrolysis and condensation polymerization in the activation phase to form the gel. Subsequently, the gel is applied as a coating to the substrate and is dried to create a hard, glossy film.
Is Sol-gel Considered a Ceramic?
Sol-gel is not a ceramic. The associated technology is a mix of totally different chemistry types, namely organic and inorganic. Although sol-gel coatings carry many of the same characteristics as ceramics, they do so to a lesser degree.
What Makes Sol-gel Nonstick?
The good thing is that sol-gel nonstick coatings are free of fluoropolymers, but how is that possible? Sol-gel coatings are mixed materials and as such exhibit the strength of silica while featuring great release and outstanding smoothness without the need for fluoropolymers. The release or nonstick properties are an inherent characteristic of this kind of coatings.
Sol-gel Versatility and Consumer Use
Sol-gel technology is very versatile and its applications are as colorful as producing some of the world's lightest materials to creating some of its toughest ceramics. One of the rather extensive areas of application for sol-gel technology is the creation of thin films or coatings. The coatings can be of protective or decorative nature and can be applied to a wide range of materials (called substrates) including glass and metal. Putting protective coatings on cooking utensils or other basic housewares is just one application, although a more well-known to the public, of sol-gel technology.
Sol-gel's Growing Acceptance
Sol-gel coatings feature a wider range of colors, like blue, red, green and even white, and are able to preserve the color at higher temperatures. The technology also produces high gloss coatings that have the ability to withstand higher temperatures compared to conventional coatings, giving cookware a better look and enhanced functionality.