## 2 Results and Discussion
### Solvent-Selective Swelling of the PSt-\(l\)-PDMS and PSt-\(l\)-PDMS/DVB Conetwork Gels  
The swelling behavior of crosslinked polymers is a critical property which provides insights into their structural characteristics as well. In order to reveal whether a solvent which is only solvent for one of the components in the PSt-\(l\)-PDMS and PSt-\(l\)-PDMS/DVB conetworks is able to swell preferentially the given component, detailed swelling experiments  
Figure 5: The AFM images of the PSt-\(l\)-PDMS and PSt-\(l\)-PDMS/DVB conetworks (the dark areas belong to the PDMS phases, the lighter, yellow color corresponds to the PSt domains; image sizes: 500 \(\times\) 500 nm). were carried out with 1-nitropropane (1-PrNO\({}_{2}\)) and n-hexane. Among these, 1-PrNO\({}_{2}\) is a good solvent for PSt but is a non-solvent for PDMS, as found during preliminary solubility tests, while hexane is a good solvent for PDMS, but PSt is insoluble in this solvent. As shown in Figures S1 and S2, the swelling degrees were measured as a function of time until equilibrium swelling was achieved for all the samples (with the exception of sample SD5-4.7-75, which disintegrated after a relatively short time when swelling in hexane). As presented in these Figures, both solvents are able to swell the conetworks, and the initial rates of swelling and the equilibrium swelling degrees (\(Q_{\rm e}\)) depend on the composition. The \(Q_{\rm e}\) values obtained in both 1-PrNO\({}_{2}\) and n-hexane are displayed in Figures 6 and S3 as a function of PDMS content. The data in these Figures clearly indicate that swelling capacity, i.e., \(Q_{\rm e}\) decreases in 1-PrNO\({}_{2}\), while it increases in n-hexane with increasing PDMS content. It can also be seen in Figure S3 that the presence of DVB decreases the equilibrium swelling degrees for a given composition in 1-PrNO\({}_{2}\) only in the case of conetworks with 5:1 St/DVB (\(m/m\)) ratio, indicating that the PDMS content is the determining factor of \(Q_{\rm e}\) even at relatively high, that is, at 36:1 St/DVB (\(m/m\)) ratio. In contrast, the \(Q_{\rm e}\) in hexane decreases with increasing DVB content in the conetworks (Figure S3). The relatively high \(Q_{\rm e}\) values even at relatively low and high PDMS contents in both solvents confirm the bicontinuous phase separation in these conetworks indicating that the non-swelling phase does not restrict the solvent diffusion in the continuous other phase. As also displayed in Figures 6 and S3, the selective swelling behavior in terms of \(Q_{\rm e}\) of the PSt-\(l\)-PDMS and PSt-\(l\)-PDMS/DVB double-hydrophobic conetwork gels enable preliminary design of such materials with predetermined swelling capacity in the investigated solvents in a wide range of \(\sim\)20-300% equilibrium swelling degree. Additionally, revealing the swelling mechanism was also attempted by using the Korsmeyer-Peppas relationship [113] between the swelling degree (\(Q_{l}\)) and swelling time (\(t\)):  
\[Q_{t}=k\!\cdot\!t^{n} \tag{1}\]  
where \(k\) is a constant and \(n\) is called as diffusion exponent [113; 114; 115; 116]. The double logarithmic plot of \(Q_{l}\) and the swelling time (\(t\)) in the initial stage of swelling according to Equation (2), that is,  
\[\log(Q_{l})=\log(k)+n\cdot\log(t) \tag{2}\]  
affords the determination of the diffusion exponent. As shown in Figure S4, the \(\log(Q_{l})\) versus \(\log(t)\) plots provide a linear relationship for the swelling in both 1-PrNO\({}_{2}\) and hexane for all the conetwork samples. The slopes of the straight lines give the diffusion exponent (\(n\)) values, which are displayed as a function of PDMS contents of the conetworks  
Figure 6: The equilibrium swelling degrees of the PSt-\(l\)-PDMS and PSt-\(l\)-PDMS/DVB conetworks in hexane and 1-nitropropane. in Figure 7. In this Figure a line at \(n=0.45\) value indicates Fickian diffusion of the solvent molecules. However, the diffusion exponents range from 0.25 to 0.44 in 1-PrNO\({}_{2}\) and from 0.15 to 0.46 in hexane, with one exception in the latter case.