(a) A confocal microscopy image of the monodisperse PMMA-PHSA in dodecane. (b) A polarized optical microscopy (POM) photograph of a single colloid dispersed in 5CB with the far-field director aligned with the analyzer indicating quadrupolar distortion of the director at the particle surface. (c) A confocal microscopy image of f ¼ 33% dispersion in 5CB. (d) A POM image of dispersion of f ¼ 30% particles dispersed in 5CB, compressed to a sample thickness of 5 μm. Black lines connecting black circles provide direct evidence of disclinations linking neighboring particles (both are isotropic within the birefringent background). All scale bars equal 6 μm in length. For POM images, orientation of the orthogonal polarizer (P) and the analyzer (A) are shown.

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... confocal microscopy image of dense (f 50%) dispersion in dodecane shows that particles do not aggregate in an isotropic solvent, as shown in Fig. 2(a). In Fig. 2(b), a single particle imaged using polarized optical microsopy reveals quadrupolar distortion of the director field, indicating weak homeotropic anchoring of the director at the surface of the PMMA-PHSA particles [38]. A dispersion of f ¼ 33% in 5CB, imaged through confocal microscopy reveals colloid aggregation and nematic ...

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... confocal microscopy image of dense (f 50%) dispersion in dodecane shows that particles do not aggregate in an isotropic solvent, as shown in Fig. 2(a). In Fig. 2(b), a single particle imaged using polarized optical microsopy reveals quadrupolar distortion of the director field, indicating weak homeotropic anchoring of the director at the surface of the PMMA-PHSA particles [38]. A dispersion of f ¼ 33% in 5CB, imaged through confocal microscopy reveals colloid aggregation and nematic (dark) domains ...

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... optical microsopy reveals quadrupolar distortion of the director field, indicating weak homeotropic anchoring of the director at the surface of the PMMA-PHSA particles [38]. A dispersion of f ¼ 33% in 5CB, imaged through confocal microscopy reveals colloid aggregation and nematic (dark) domains of irregular shape and size of a 10 μm, as shown in Fig. 2(c). A composite of f ¼ 30%, flattened between two untreated glass cover slips with a gap of 5 μm and imaged between crossed polarizers, is shown in Fig. 2(d). The nematic liquid crystal medium is birefringent appearing in various shades of gray, brightest (white) when the director is at 45 , and darkest (black) at 0 to the polarizers. ...

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... particles [38]. A dispersion of f ¼ 33% in 5CB, imaged through confocal microscopy reveals colloid aggregation and nematic (dark) domains of irregular shape and size of a 10 μm, as shown in Fig. 2(c). A composite of f ¼ 30%, flattened between two untreated glass cover slips with a gap of 5 μm and imaged between crossed polarizers, is shown in Fig. 2(d). The nematic liquid crystal medium is birefringent appearing in various shades of gray, brightest (white) when the director is at 45 , and darkest (black) at 0 to the polarizers. Isotropic particles appear as black circles and disclinations (having an isotropic core) appear as black lines connecting neighboring particles. This provides ...

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... as shown in Fig. 3(b), collected for f ¼ 25% composites on a cone-plate geometry for "up" and "down" sweeps, does not appear to affect the value of γ c that has a wide range of values between 0:2% , γ c , 5% and does not appear dependent on volume fraction, as indicated in Fig. 3(c). Visual observations under confocal microscopy, as shown in Fig. 2(c), reveal that the microstructure is highly heterogeneous. Measurements of γ c are highly scattered since the structure yields first in the weakest regions of the network and then flows as clusters until the clusters break-up at high shear rates. The magnitude of the moduli takes around 1 min to recover [3], which is beyond the timescale ...

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... colloidal network is filled with a pure nematic solvent, self-organizing to have an average domain size a, as illustrated in Fig. 9(b) and observed experimentally in Fig. 2(c). Since each colloid surface and each disclination provide homeotropic anchoring, we expect each nematic domain to have radial alignment, although distorted due to the irregular shape of each domain. If the domain were circular, it would have a single central defect with topological charge, S ¼ 1, as described by Terentjev et al. [23]. ...

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... in size any further. This limit will drive structural rearrangements elsewhere in the system before a reduces further (e.g., at high colloid concentrations). We presume W ¼ 1:5 Â 10 À7 J/m 2 , consistent with earlier estimations [23]. Using K ¼ 5:5 pN, we expect the magnitude of a 10 μm, which is consistent with our experimental observations Fig. ...