The properties of (synthesized) single-walled aluminosilicate nanotube (AlSiNT; light-scattering characterized length ∼2000 ± 230 nm and diameter ∼35 ± 4 nm) dispersed in an aqueous poly(vinyl alcohol) (PVA) solution (10 wt %) are systematically explored using a comprehensive combination of (polarized/depolarized) dynamic light scattering, rheological, rheo-optical, and scanning electron microscopy analysis schemes. The nanotube/polymer dispersions under investigation are promising for their fair nanotube dispersion in pristine aqueous media (e.g., without salt or acid addition), as well as for the optical transparency that greatly facilitates systematic exploration of structural features and dispersion state that are practically inaccessible for many of their (opaque) companions such as carbon nanotube dispersions. We provide the first in-depth analysis revealing excellent dispersion state of (unmodified) AlSiNT in the PVA matrix, giving rise to (critical) gel-like features and substantially promoted elasticity that can be utilized, as a practical assessment, to produce uniform and defect-free electrospun nanofibers. Additionally, there is unambiguous evidence of nematic liquid crystal-like "wagging" (strain-invariant, periodic oscillation) under steady shear flow, a phenomenon previously unreported for nanotube composite materials. Overall, the present findings suggest that AlSiNT/PVA dispersions possess promising rheological, optical, and electrospinning properties that are highly desirable for current nanotechnological applications, and may serve as an ideal model system for establishing structure-performance relationships for like nanotube/polymer composite materials.

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Modifying the consistency of a given edible fluid matrix by incorporating food thickeners is a common nursing remedy for individuals with dysphagia when adequate water consumption is a concern. As apple pectin (AP) offers nutraceutical benefits, properly formulated apple pectin (AP)-based thickeners featuring xanthan gum (XG) can be superior candidates for preparation of dysphagia-friendly matrices (DFMs). Our recruited DFMs exhibit fluid-like behavior (loss modulus > storage modulus, G” > G’) at lower AP concentrations (2 and 5%, w/w); they turn into weak/critical gels (G’ ≈ G”) as the concentration becomes higher (9%). In contrast, XG-DFMs display gel-like attributes with G’ > G”, even at rather low concentrations (<1%) and become more resistant to sugar, Na+, and Ca2+ modifications. The composite matrix of AP1.8XG0.2 (constraint at 2%) exhibits a confined viscosity of 278 ± 11.7 mPa∙s, which is considered a DFM, in comparison to only AP- or XG-thickened ones. The hardness measurements of XG0.6 and AP1.2XG0.8 are 288.33 ± 7.506 and 302.00 ± 9.849 N/m2, respectively, which potentially represent a promising formulation base for future applications with DFMs; these textural values are not significantly different from a commercially available product (p > 0.05) for dysphagia nursing administrations.

The percolation behaviors of a series of high-structured carbon black (CB) pastes (CB weight fractions 10–25 wt%, ethyl cellulose as the binder, α-terpineol as the solvent) were systematically investigated using analyses of rheology and impedance spectra together with characterization via small-angle X-ray scattering (SAXS) and scanning electron microscopy (SEM).

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