Figure 1

Phase separation of mixtures of $fd$ and $fd$-PEG at 110 mM ionic strength ($d=3.7$), $p$H 8.2. The phase diagram is presented in (a). The dark curves are guides to the eye representing the phase boundaries of the two nematic phases and the isotropic phase. The dashed lines indicate coexisting samples, and the three-phase region is indicated by the gray triangle. The coexisting phases labeled in (a) as viewed under crossed polarizers are as follows: (b) I-N coexistence; (c) highly fractionated I-N coexistence; (d) I-N-N three-phase coexistence with a schematic representation of the partitioning of thick and thin rods shown in (e); (f)  N-N demixing just above the triphasic region; and (g) highly concentrated N-N coexistence showing strong partitioning of the thick (yellow, $fd$-PEG) and thin (white, $fd$) rods. The isotropic phase appears dark and the nematic phase appears light due to its birefringence. (h) Differential interference contrast microscopy image of low density $fd$-PEG-rich nematic tactoids in coexistence with high density $fd$-rich nematic bulk phase.Reuse & Permissions

Figure 2

Phase diagrams of suspensions of $fd$-PEG mixed with $fd$ at (a) 60, (b) 50, and (c) 5 mM ionic strength, $p$H 8.2. The legend for all three diagrams is in (c). The single nematic phase (open triangles) is determined by fluorescence microscopy. As in Fig. 1, the dark curves represent the phase boundaries and the dashed lines indicate coexisting samples. The three-phase region in (a) is indicated by the gray triangle.Reuse & Permissions

Figure 3

(a) Characterization of the binary phase behavior of rods of equal length obtained with PL scaling of the Onsager free energy as a function of the inverse diameter ratio $1/d$ and $L/D_{\mathrm{t}\mathrm{h}\mathrm{i}\mathrm{c}\mathrm{k}}$. I-N-N coexistence is found below the uppermost line. Coalescence of the upper and lower N-N critical points occurs at the dashed line (region $\gamma$), and I-I-N coexistence becomes stable below the lower line (region $\delta$). For $L/D_{\mathrm{t}\mathrm{h}\mathrm{i}\mathrm{c}\mathrm{k}}<7$, the lower critical point merges with the I-N coexistence region at the uppermost solid line. The phase diagrams, presented in units of $c_i=v_i{N}_i/V$, are calculated for $L/D_{\mathrm{t}\mathrm{h}\mathrm{i}\mathrm{c}\mathrm{k}}=24$ with $d=4.4$ (b), $d=5$ (c), and $d=5.2$ (d). Three-phase coexistence is indicated by the gray triangle.Reuse & Permissions