Only two other examples actively exploit the salting-out effect and both cases use CS (Figure ). In a socalled "soak n' boost" strategy, SIPNs made from covalently cross-linked PAAm and short-chain CS, are soaked for 20 minutes in either alkaline 1 M NaOH or saturated NaCl solutions. The former is believed to produce microcrystalline domains transforming the SIPN into a stiff and tough double network (Γ = 12.9 kJ/m 2 , E = 0.319 MPa). In the latter case, a classic salting-out effect is achieved and while this double network is slightly stiffer (E = 0.358 MPa), the fracture energy is lowered (Γ = 8.3 kJ/m 2 ). The water content following the soaking step, however, was not determined and is expected to change due to swelling/shrinking. Overall, tough hydrogels obtained through microcrystallization managed to reach new heights in fracture energies and stiffness, while exhibiting moderate water contents.