This work focuses on the development and comprehensive characterization of cationically functionalized, biodegradable polyvinyl alcohol (PVA) for use in sustainable hair care formulations. Frequent hair coloring leads to rapid color fading during washing, creating a strong demand for film-forming ingredients that can preserve color for longer. Since the hair surface is predominantly negatively charged, cationic polymers are especially suitable for achieving strong electrostatic attachment and forming a stable protective film. At the same time, modern rinse-off cosmetics must meet high environmental standards, as they inevitably enter aquatic environments. Biodegradable PVA, known for its excellent film-forming ability, broad industrial applicability, and straightforward chemical modifiability, offers a promising foundation for combining performance with sustainability.

The synthesis of functionalized PVA derivatives was carried out using various chemical strategies, allowing the introduction of cationic groups while maintaining the polymer’s inherent properties. Structural and physicochemical characterization was performed using 1H and 13C NMR spectroscopy, elemental analysis, and gel permeation chromatography. Biodegradability was evaluated using well-established tests, such as OECD 301, to ensure ecological compatibility. Furthermore, practical application tests on natural and dyed hair strands were conducted to evaluate performance under realistic conditions.

The functionalized PVA is expected to demonstrate enhanced affinity to hair, improved adhesion of protective films, and contributed to perceivable hair care effects. This study highlights the potential of functionalized, biodegradable PVA to combine effective cosmetic performance with environmental responsibility, offering a promising platform for the development of innovative, eco-friendly hair care products.