Molecular Mechanisms of Stress Development in Polysaccharide Films: Insights for Biopolymer Design in Cosmetic Applications

The transition from synthetic polymers to biobased polysaccharides in cosmetic formulations requires an understanding of the fundamental physical and chemical properties that govern their performance. In this study, we investigated six polysaccharides and a reference synthetic polymer by measuring key properties including glass transition temperature, crystallinity, viscosity, elastic modulus, and concentration evolution during drying. These measurements enabled the development of a quantitative model that accurately predicts the final mechanical stresses arising in polysaccharide films during the drying process. We demonstrated how crystallinity and viscosity influence stress development, providing mechanistic insights into film mechanics and their interactions with substrates such as skin for cosmetic applications. This approach is based on fundamental polymer physics and can be extended to other film-forming systems to support the integration of sustainable biopolymers.