Figure 1.
Mixing pressure πmix=π−πelas−πion of polyacrylate gels vs gel volume fraction ϕ in salt solutions containing 40 mmol∕l NaCl plus various amounts of CaCl2 at room temperature; data from Horkay and co-workers (Refs. 9, 27). The curves show Eq. 2 fitted to the data; χ0 and χ1 are shown in Fig. 8.