Predicting the effects of degradation on viscoelastic relaxation time using model transient networks

In this study, we utilized tetra-armed polyethylene glycol (Tetra-PEG) slimes, which are model transient networks with well-controlled structures, to predict the effects of long-term degradation on the viscoelastic properties of liquids. Viscoelastic liquids, such as sodium hyaluronate, are frequently used in biomedical applications within the human body. However, precisely controlling the viscoelastic properties of these liquids in the long-term is challenging, as the main chains of the liquids undergo stochastic degradation. To establish a predictable model for studying long-term degradation effects, we employed Tetra-PEG slime, and modifications were performed to introduce specific cleavage sites in areas with connections. The Tetra-PEG slimes were characterized by single relaxation modes, and these modes were independent from the degree of degradation, which was determined by hydrolyzing the cleavage sites. Overall, this work provides a universal design for viscoelastic liquids with precisely-controllable degradation.