Effects of molecular weight of methylphenyl‐containing vinylsiloxy‐functionalized terpolysiloxanes on their UV‐activated crosslinking by hydrosilylation at room temperature in air, shelf life stability of “all‐in‐one” pastes prepared from them for additive manufacturing, and mechanical properties of the resulting crosslinked elastomers, are investigated. It is found that while rheology of pastes containing base polymers, trimethylsilylated silica fillers, and thixotropic additives is not significantly affected by the base polymer molecular weight but is dominated by the filler concentration, the pastes based on higher molecular weight polymers exhibit faster crosslinking (corresponding to higher catalyst turnover numbers) and their crosslinked elastomers show transient strain‐induced crystallization. The latter appears in networks from terpolymers with degrees of polymerization (DP) of 240 and above (corresponding to about one half of the critical polydimethylsiloxane chain length for entanglement formation of DP = 460), within the temperature range of −80 to −30 °C, characteristic for polydimethylsiloxane melting transition. It is believed that this is the first time an observation of this chain length effect is reported for polysiloxane elastomers and that the properties reported herein can be expected to have major implications on the application potential of these polymers in both additive manufacturing and performance of their elastomers at sub‐ambient temperatures.

In search of "inks" for additive manufacturing of silicone rubber parts, three different types of "all-in-one" pastes with suitable rheological flow properties, ultraviolet (UV)-activated fast cross-linking by hydrosilylation in air at room temperature (as quick as 20−30 s), and shelf lives of over six months in the dark and 6−9 days in laboratory daylight, depending on paste composition, have been developed. The pastes are based on vinylsiloxy-functionalized, completely amorphous, linear terpolysiloxanes containing predominantly dimethylsiloxy-, DiMeS, repeat units with small amounts (typically less than 5 mol %), of diphenylsiloxy-, DiPhS, methylphenylsiloxy-, MePhS, or diethylsiloxy-, DiEtS, crystallization disruptors. The base polymers were compounded with trimethylsilylated hydrophobic silica fillers, thixotropic flow agents, hydrosilyl-functionalized oligomeric crosslinkers, and catalytic systems containing either platinum(II) acetylacetonate, Pt(AcAc) 2 , or trimethyl(methylcyclopentadienyl)platinum(IV), MeCpPtMe 3 , and diethyl azodicarboxylate, DEAD, catalyst inhibitors. Paste preparation, steady and oscillatory shear rheology, and UV-activated cross-linking and shelf-life stabilities are described.

Electrochemical arrays promise utility for accelerated hypothesis testing and breakthrough discoveries. Herein, we report a new high-throughput electrochemistry platform, colloquially called "Legion," for applications in electroanalysis and electrosynthesis. Legion consists of 96 electrochemical cells dimensioned to match common 96-well plates that are independently controlled with a fieldprogrammable gate array. We demonstrate the utility of Legion by measuring model electrochemical probes, pH-dependent electron transfers, and electrocatalytic dehalogenation reactions. We consider advantages and disadvantages of this new instrumentation, with the hope of expanding the electrochemical toolbox.

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Since imidazole is easily protonated and well known to coordinated to various transition metals, its incorporation into a polymer with ferrocene may result in interesting electronic interactions between the ferrocenyl and imidazolium moieties. To this end, copolymers of vinylferrocene and vinylimidazole were prepared in various ratios by free radical polymerization. The interactions between the ferrocenyl and imidazolium moieties were studied by cyclic voltammetry, UV-Vis spectroscopy and density functional theory (DFT) studies. Cyclic voltammetry of polymer thin films showed multiple oxidation waves at low pH or in the presence of Pb 2+ or Cd 2+ ions. The UV-Vis spectrum of thin films showed an additional absorbance at 625 nm suggesting electronic interactions. In addition, DFT studies indicated that the morphology of the polymer would place some of the ferrocenyl and imidazolium moieties in close proximity.