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The chitosan-Schiff base supported palladium and cobalt bimetallic complex was synthesized in a simple method and characterized by Fourier-transform infrared spectroscopy (FT-IR), powder X-ray diffraction (XRD), and X-ray photoelectron spectra (XPS). It was found that the catalyst has great activity and stability in the coupling of acrylamide (AA) with the phenyl halide. The influence of various bimetallic catalysts, the different molar ratio of Co/Pd, the bases, the amount of the catalyst and base, and the molar ratio of iodobenzene/AA on the reaction were investigated. The results showed that the catalytic activity of the molar ratio of Co/Pd (3/1) was the best when the iodobenzene was used as a substrate. The yield of the cinnamamide did not change significantly after ten runs. It has been revealed that the catalyst was efficient for the reaction.a The binding energies are referenced to C 1s (284.6 eV), and the energy differences were determined with an accuracy of AE 0.2 eV.

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such as dependence of the mole fractions in the copolymer on the mole fractions of unreacted monomers in solution, variation of copolymer compositions with conversion and sequence length distribution. The fluidity and flow loss of pastes containing PCEs were investigated, and the appropriate PCEs dosages resulted in a better workability of cement pastes.

Polycarboxylic superplasticizers produced by polyether macromonomers have attracted widely attention recently. Polyether macromonomers can be divided into vinyl ether‐based and vinyl alcohol‐based macromonomers according to the starting agents (vinyl ether and vinyl alcohol, respectively). In this study, three vinyl ether‐based macromonomers were synthesized to compare with vinyl alcohol‐based macromonomers that commonly used at present. It was found that the three vinyl ether‐based macromonomers all can be copolymerized at lower reaction temperature (5 °C) and shorter reaction time (30–45 min) when the same reaction conversion ratio was achieved. To better explain the high activity of vinyl ether‐based macromonomers, the molecular structure of different polyether macromonomers was calculated. The results show that the electron cloud on the CC double bond of vinyl ether‐based macromonomers exhibits more obvious deflection because of the direct connection with the oxygen atom, which makes it more easily to copolymerize with acrylic acid. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48844.