Surfactant-induced healing of tough hydrogels formed via hydrophobic interactions

Supramolecular Polymer Networks: Preparation, Properties, and Potential

“…However, when swollen in water, such hydrogels lose their ability to self-heal as a result of the extraction of SDS micelles from the gel network by dilution and washing procedures. Recently, Okay and coworkers reported that complete healing of these swollen physical gels is achievable by treatment of the damaged area with an aqueous solution of wormlike SDS micelles [264].…”

Self-Healing Hydrogels Formed via Hydrophobic Interactions

“…For surfactant-containing hydrogels, the linear viscoelastic regime extends up to approximately 100 % strain, whereas it is restricted to strains up to~10 % for surfactant-free hydrogels. This difference shows a significant decrease in the stretchability of these hydrogels upon removal of surfactant [33,40]. Figure 17b represents tensile stress-strain data of HM PAAm hydrogels prepared at three different concentrations (C 0 ).…”

“…29a, stress-strain curves of a virgin HM PAAm gel sample without SDS (dashed curve) and gel samples healed by addition of an SDS solution (solid curves) are shown. The fracture stress after 1 h of healing is 25 AE 5 kPa, which is almost twice the fracture stress of the virgin gel sample containing SDS [40]. For healing times ranging from 30 min to 9 h, the healed region of the gels is more swollen than the gel bulk region.…”

“…Another stimulus to trigger self-healing in hydrogels formed via hydrophobic interactions is the treatment of the damaged area of the gels with an aqueous solution of wormlike surfactant micelles [40]. In Fig.…”

“…Uniaxial compression and tensile measurements on hydrophobically modified hydrogels serve to evaluate their elastic properties such as moduli, fracture stresses, and deformation ratios at break [33][34][35][39][40][41][42]. The stress is presented by its nominal, σ nom , or true values, σ true (equal to λσ nom ), defined as the forces per unit undeformed and deformed area, respectively; λ is the deformation ratio.…”