PVP
PVP stands for Poly Vinyl Pyrrolidone, a large synthetic polymer made from repeated units of Vinyl Pyrrolidone (VP). It was the first synthetic polymer introduced as a hair fixative in the 1950s, replacing insect-derived Shellac. PVP attaches to surfaces such as hair and skin, forming a thin, even film; however, this film is somewhat brittle and hygroscopic, meaning it is sensitive to moisture and humidity.
PVP's primary benefit is its film-forming ability, which helps hold hairstyles and extend the wear of color cosmetics and sunscreens. It also functions as a viscosity controller and emulsion stabilizer in formulations.
The film formed by PVP is brittle and hygroscopic, causing it to break down in high humidity; this limits its effectiveness as a hair fixative in humid conditions. Humidity-resistant alternatives such as VP/VA Copolymer are often used to address this limitation.
