SUMMARY

This project aims at developing robust methods to characterize the mechanical, transport and adhesion properties of soft hydrated materials based on indentation technique. In this project, proper experimental procedures are developed for carrying out indentation at small length scales, which can be applied on instruments such as the atomic force microscope and the micro-indenter. Specifically, the project includes two methods, the dynamic indentation method and the indentation adhesion method. For the dynamic indentation method, a procedure for extracting the linear poroelastic parameters is proposed, which is simpler compared with existing methods. In the indentation adhesion method, the adhesion behavior of the material is obtained at different time and length scales to study the contribution from several mechanisms special for hydrogels. The contact mechanics model able to describe the length-dependent adhesion is developed. The two methods in this project are then applied to other representative hydrogel systems and soft hydrated biological materials.