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YbPc-900 and LaPc-1000 derived from rare earth phthalocyanines present graphite-layered structure with smaller particles and larger specific surface area, which result in smaller impedance, better conductivity, faster Li+ transport and excellent energy storage behaviors.

Rheological measurements typically require at least 20–50 mg of sample. We set up a miniaturized sliding-plates shear rheometer (mgRheo) that requires only 2 mg sample or even less. We designed a flexure-based force-sensing device that could measure force ranging from the micronewton to millinewton scale, e.g., 40 μN–400 mN for one particular spring constant. The setup was strain-controlled by a piezostage and could perform standard rheological tests such as small amplitude oscillatory shear, step strain, and stress relaxation. The accuracy and consistencies were evaluated on polydimethylsiloxane viscoelastic standard, entangled poly(hexyl methacrylate), and polystyrene. The obtained phase angles quantitatively agreed with those from commercial rheometers. The exact values of the modulus are prone to the overfilling of the sample. The storage G′ and loss G″ moduli from the mgRheo were systematically higher than those from commercial rheometers (i.e., within 5% with careful trimming or 30% with excessive overfilling). Between 102 and 106 Pa, G′ and G″ were in good agreement with commercial rheometers. Such a setup allowed for general rheometric characterizations, especially obtaining linear viscoelasticity on soft matters that are synthetically difficult to obtain in a large quantity.

The persistent erythema and flushing seen in some cases of rosacea do not respond effectively to, or may easily relapse after, oral medication or light-based therapies (laser or intense pulsed light). Intradermal botulinum toxin A (BTX-A) injection can be used to treat intractable erythema and flushing, but studies with large samples and long-term observation have not been conducted to determine its effectiveness and safety. The aim of this study is thus to investigate the effective duration and safety of intradermal BTX-A injection for intractable erythema and flushing.Sixteen patients with rosacea with erythema telangiectasia were injected with BTX-A at 1-cm intervals between each point. Clinician Erythema Assessment (CEA) scores were obtained at baseline and 1 month after injection. Flushing assessment and survey using the Dermatological Quality of Life Index (DLQI) questionnaire were conducted at baseline and at 1, 3, and 6 months after injection.At 1 month after injection, CEA scores revealed significant improvements in erythema and flushing; the results of the questionnaire on flushing and DLQI indicated that the improvement of flushing usually lasted for 3-6 months, but the effect decreased significantly at 6 months, and individual patients needed another treatment.BTX-A significantly improves the symptoms and quality of life of patients with refractory rosacea with few adverse effects.

Alternating associative polymers (AAPs) containing more than two species of alternating hydrophobic and hydrophilic units can form unique physical network and perform interesting rheological behavior in aqueous solution. In this work, an AAP was prepared through self-assembly assisted dimerization of an anthracene-functionalized telechelic associative polymer (AnTAP) in aqueous solution by light irradiation. It is demonstrated that AnTAP can in situ chain extend to AAP with well-defined linear structure and ultrahigh molecular weight through dimerization reaction of anthracene moieties in the core of micelle under light irradiation. Meanwhile, the solution changes from viscoelastic liquid to a free-standing gel, because a physical network that cannot relax in a finite time window has developed along with the dimerization process. The results are therefore of interest not only for understanding the network structure and rheological properties of AAP solution, but also for preparing AAPs with ultrahigh molecular weight by self-assembly assisted photodimerization reactions.

3-dimensional architectured polymers, for example, giant molecules, present distinct dynamics from chain-like polymers and are coarse-grained as soft-clusters. There is a critical number of beads, above which their melts cannot relax under thermal energy and become cooperative glass. To reveal the role of dispersity, we study the dynamics of binary blends of giant molecules with the same glass transition temperature by rheological experiments and by molecular dynamics simulations. The large component of the blend, OPOSS24 or 141,335, contains more beads than the critical number and forms cooperative glass, while the small component contains less beads than the critical number. The gradual change of volume fraction allows us to fine-adjust the average number of beads. An abrupt slowdown happens only if the volume fraction of the large component reaches 80%. Both experimental and simulated data can be described by a Vogel–Fulcher–Tammann-like equation against volume fractions with only one fitting parameter. The divergent relaxation times can also be rewritten as a function of the average number of beads. Such abrupt dynamic slowdown has to be induced by the glass-like cooperative dynamics. The cooperative glass state may only be reached when the majority of giant molecules or generally speaking, soft-clusters, are large enough. If we regard binary blends of soft-clusters as large and small cooperative rearranging regions, this may provide a direct approach to glass problems and may shed light on our understanding.

Polydimethylsiloxane (PDMS) short chains were grafted to graphene oxide (GO) surface by one-step synthesis to form a GO ramification, which exhibited a remarkable toughening, synergistic fire retardation, and water resistance for cured epoxy nanocomposites. Small addition of 0.29 wt% of PDMS-GO with 0.3 wt% of P made the cured epoxy reach the UL94 V-0 level with LOI of 29.2, T 5wt% of 339 °C, char yield of 21.4 wt%. The flexible strength was significantly increased to 101.2 MPa, and the water absorption was reduced to 0.4 wt% with static contact angle of water as 108.7° for the epoxy containing 0.29 wt% of PDMS-GO. This was due to homodisperse of PDMS-GO in epoxy matrix observed with TEM. Therefore, the epoxy containing 0.3 wt% of P and 0.29 wt% of PDMS-GO was the optimal formula with the balanced performance in fire-retardation, toughness, and water resistance and is expected to satisfy electronic applications.