LAUSR.org creates dashboard-style pages of related content for over 1.5 million academic articles. Sign Up to like articles & get recommendations!

Characterization of stress softening and self-healing in a double network hydrogel

Photo from wikipedia

Abstract In this paper, a micro-mechanically based constitutive model is presented to describe stress softening and self-healing in alginate-polyacrylamide (PAAm) double network (DN) hydrogels. The stress softening phenomenon in alginate-PAAm… Click to show full abstract

Abstract In this paper, a micro-mechanically based constitutive model is presented to describe stress softening and self-healing in alginate-polyacrylamide (PAAm) double network (DN) hydrogels. The stress softening phenomenon in alginate-PAAm DN hydrogels under cyclical deformation is assumed to be the result of the rupture of chain linkages. Therefore, the network evolution method [Dargazany and Itskov, International Journal of Solids and Structures, 2009, 46, 2967] is used to characterize stress softening. The polymer matrix is initially decomposed into reversible and irreversible polymer networks. To model stress softening, the entropic energy of a polymer chain and the chain distribution are taken into account for each network. Unlike conventional DN hydrogels, after deformation alginate-PAAm hydrogels show self-healing. The rate of self-healing is associated with both intermolecular forces and the duration of storage of the samples in a thermal chamber. Broken chain linkages are assumed to rebond due to intermolecular forces and heating. Chemical reaction kinetics and heat transfer equations are utilized to calculate the quantity of the reversible cross-linking rebonding. This model contains few material parameters and demonstrates good agreement with experimental data in stress softening and self-healing.

Keywords: self healing; double network; stress softening; softening self

Journal Title: Results in Physics
Year Published: 2019

Link to full text (if available)


Share on Social Media:                               Sign Up to like & get
recommendations!

Related content

More Information              News              Social Media              Video              Recommended



                Click one of the above tabs to view related content.