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Organic radical polymers are promising cathode materials for next‐generation batteries because of their rapid charge transfer and high cycling stability. However, these organic polymer electrodes gradually dissolve in the electrolyte, resulting in capacity fade. Several crosslinking methods have been developed to improve the performance of these electrodes, but they are either not compatible with carbon additives or compromise the solution processability of the electrodes. A one‐step post‐synthetic, carbon‐compatible crosslinking method was developed to effectively crosslink an organic polymer electrode and allow for easy solution processing. The highest electrode capacity of 104 mAh g−1 (vs. a theoretical capacity of 111 mAh g−1) is achieved by introducing 1 mol % of the crosslinker, whereas the highest capacity retention (99.6 %) is obtained with 3 mol % crosslinker. In addition, mass transfer was observed in situ by using electrochemical quartz crystal microbalance with dissipation monitoring. These results may guide future electrode design toward fast‐charging and high‐capacity organic electrodes. [ABSTRACT FROM AUTHOR]

In this study, the authors report the highly efficient, multigram-scale synthesis of an ester-functionalized, poly(aniline-co-fluorene) polymer. The excellent solubility and film-forming ability of this polymer facilitate its application as a reversible battery cathode. Electrochemical quartz crystal microbalance with dissipation monitoring confirms a multi-electron transfer process, resulting in a specific discharge capacity of 51 mAh g−1 and a high reversible doping level of 0.69. Galvanostatic cycling at 1 C demonstrates excellent electrode stability with a capacity retention of 95.2% after 100 cycles. Therefore, this work demonstrates a novel electroactive polymer that exemplifies how chemical functionality may be used to properly balance processability and electroactivity of macromolecular battery cathodes. [ABSTRACT FROM AUTHOR]

Wine mouthfeel and astringency play an important role in shaping the organoleptic quality and have been associated with tannin-salivary protein colloidal interactions. The mechanistic drivers of wine mouthfeel, especially those creating distinct astringency sub-qualities percepts, are yet to be fully realised due to the lack of appropriate measures. This study researched the friction behaviours of saliva-wine interactions, that allow inference of insights into the physicochemical origins of several important wine mouthfeel attributes. The red wine sample sets were created by doctoring various levels of ethanol, tannin, pH and mannoprotein on a Malbec. Samples were profiled sensorily and chemically. The friction behaviours of wine-saliva interaction and salivary viscoelasticity were investigated by soft-tribological protocols plus quartz crystal microbalance with dissipation. The sensory scores of mouthfeel attributes were modelled by physicochemical parameters using partial least squares regression. Results suggested that burning and resalivation are non-frictional-derived sensations driven by ethanol and acidity, respectively. Drying , grippy and rough are driven by tannin's adsorption on salivary film, which cause poor lubricity and a film strip-off thus exhibit as high boundary friction in tribology. Pucker is not directly driven by tannin but the weak viscoelasticity of salivary film, which is exhibited as the fast rate of friction increase in tribology. Smoothness is driven by less salivary protein precipitation, a highly viscoelastic salivary film, or the viscosity effects from mannoprotein. Fullness is driven by high viscosity by high ethanol. These models support the theory that wine mouthfeel attributes have dissimilar physicochemical origins that lead to distinct sensory experiences. [Display omitted] • Burning / resalivation are non-frictional percepts driven by high ethanol/acidity. • High tannin drives drying/rough/grippy as high saliva equilibrium boundary friction. • High ethanol/low pH drives pucker as a fast friction increase on salivary film. • Smoothness is driven by less saliva precipitation and high mannoprotein level. • Fullness is driven by high viscosity (high ethanol) and less saliva precipitation. [ABSTRACT FROM AUTHOR]

Astringency mouthfeel is an important indicator of wine sensory quality that has been associated with colloidal interactions between tannins and salivary proteins, and a depletion in the lubricating salivary film. However, astringency is a complex sensation that has several contributing sub-qualities that may each have different physicochemical origins. We find that the model wine sample set varying in tannin, pH and polysaccharide content exhibit variations in the main sub-qualities: drying , rough and pucker. A range of soft-tribological methods involving saliva are used to gain mechanistic insight into these sub-qualities. Results suggest that rough is a secondary sub-quality that can be elicited by either drying or pucker , while these two sensations are driven by high tannin and low pH, respectively. Samples with 'chemically-equalised' astringency, which have similar colloidal stability upon interaction with saliva (saliva precipitation index), are also found to have varying sub-qualities and tribological responses. The boundary friction of saliva-wine mixtures in Stribeck curve aligned with drying , and the rate of increase in boundary friction of a salivary pellicle upon contacting wine aligned with pucker. Rough is not found to scale with any physical measure we explored. Quartz crystal microbalance indicated that the tannin, rather than pH, interacts with the salivary protein film to cause an increase in surfaces adsorbed mass in the absence of significant shear. The results indicate that while tannin and acid both contribute to the perception of astringency, the mechanisms by which they do this have different origins that lead to differences in sub-qualities. Image 1 • Samples with chemically-equalised astringency exhibited different sub-qualities. • Rough is a secondary sub-quality elicited by either drying or pucker. • Higher tribology boundary friction associated with high tannin is linked to drying. • Lower pH linked to pucker and a faster collapse of salivary pellicle in tribology. • Higher tannin increased adsorbed mass on the salivary film in QCM-D. [ABSTRACT FROM AUTHOR]