The relation between adhesion properties and network properties of hydrogels: A study based on an indentation adhesion method

Hydrogel adhesion plays a significant role in many applications. A systematic study of the surface interaction between hydrogels and other surfaces is critical importance. In this study, we carry out indentation tests on polyacrylamide wide range compositions, across contact sizes, over times. Based new model that recently developed for can describe length-dependent adhesion, extract properties including energy, cohesive strength separation distance from measurements. It found hydrogel exhibits hysteresis. The possible mechanism contributes to time-dependent discussed. also it has more direct correlation with network features, rather than conventionally discussed energy. Specifically, linearly proportional chain density all compositions tested study. Moreover, by comparing estimated length obtained measurements, concluded dangling chains are significantly longer play contributing hydrogels.