Fig. 2.

Maximum level of swelling, ${\varphi }_0$, of SPI gels as function of $y_{p,SPI}^I$ (solid line $0.224y_p-0.0224$, $R^2=0.99$; Fig. 2a), and elastic Young's moduli of swollen SPI gels as function of ${\varphi }_0$ (solid line $a{\varphi }_0^{\beta }$ with $a=7.59\times {10}^7$ and $\beta =2.28$, $R^2=0.98$; Fig. 2b). n = 3 for $y_{p,SPI}^I$, n = 2 for E, and n = 3 for ${\varphi }_0$.