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A novel boron‐containing novolac (triphenyl borate‐formaldehyde resin, TPBF) was synthesized. The structure, thermoplasticity, molecular weight, and molecular weight distribution of TPBF have been characterized with FT‐IR, melt viscosity, 13C NMR and GPC. The thermal stability of TPBF was investigated by TGA, indicating the thermal stability of TPBF was much better than that of normal novolac (phenol‐formaldehyde resin, PF). TPBFs with different molar ratios of formaldehyde to benzene ring in triphenyl borate (TPB) were also synthesized and compared for molecular size, polydispersity and thermal stability. Further, the thermal degradation kinetics of TPBFs and PF were studied by TGA using Madhusdanan‐Krishnan‐Ninan method and the activation energies were calculated at different degradation stages. It was found that the thermal degradations of TPBFs and PF are a multistage reaction and the degradation reactions in every stage follow the first order reaction mechanism. Finally, the activation energies of thermal degradations of novolac increase with the introduction of boron, the progress of degradation reaction as well as the increase of molar ratios. [ABSTRACT FROM AUTHOR]

Hollow mesoporous carbon spheres (HMCSs) have widely used in energy storage, catalysis, adsorption and other fields, but the precise construction still faces challenges. Herein, by adjusting the hydrolysis/condensation rates between tetraethyl orthosilicate (TEOS) and resorcinol, a kinetics-controlled ultra-fast co-assembly strategy is used to efficiently and conveniently construct a kind of deft HMCSs with tunable mesoporous channels and cavity sizes. Profiting by the highly interconnected three-dimensional nano-spaces, the HMCS with pore size of ∼12.2 nm has a specific surface area of 1231 m2 g−1, showing excellent performance of supercapacitor. Notably, the capacitance of HMCS reaches 294 F g−1 at the current density of 1 A g−1 in 6 M KOH electrolyte. In addition, 85 % of initial capacitance can be retained after 10000 cycles in a two-electrode system. These HMCSs have abundant large mesoporous, controllable structure, convenient preparation technology, which are expected to be more applied in the electrochemical field. [Display omitted] • HMCS is prepared by a kinetics-controlled superfast co-assembly strategy. • The pore structure and morphology can be easily regulated by temperature. • HMCS possesses large mesoporous size and high specific surface area. • HMCS exhibites high supercapacitor performance. [ABSTRACT FROM AUTHOR]

Nano α-glycine crystals, γ-glycine crystals, and amorphous solid dispersion (ASD) of glycine were prepared through solvent-free ball milling of commercial α-glycine. The solid-state polymorph conversion of glycine from α to γ was completely realized by ball milling with 0.2 wt.% NaCl for 1 h or by ball milling with 0.02 wt.% NaCl for 1 h with subsequent storage for one week. The ASD of glycine was prepared by ball milling α-glycine with an equal amount of CaCl 2 for 1 h. We studied the effect of inorganic salt types and their concentrations on the extent of polymorph conversion and amorphization of glycine in our experiments. This solvent-free ball milling method could be used for the synthesis of polymorphs and amorphous phase of drugs and other organic materials. [ABSTRACT FROM AUTHOR]

Abstract: Hollow nanospheres of Sn–Sb–Cu alloy composites have been successfully synthesized via co-reduction of metal chlorides in aqueous alkaline solution without using any surfactants or solid templates. A bubble assisted growth mechanism is proposed to account for the formation of the hollow nanostructures. The concentration of the reactants kinetically controls the nucleation rate of the alloy nuclei, making for the formation of the hollow nanospheres. Compared with the alloy nanoparticles, the hollow spheres exhibit relatively high electrochemical capacity and good cyclic retention when used as anode materials for lithium-ion batteries. The bubble assisted synthesis method can be readily explored for fabricating hollow nanostructure of other alloy system for functional material applications. [Copyright &y& Elsevier]