Functional hyperbranched polymers,as an important class of materials,are widely applied in diverse areas.Therefore,the development of simple and efficient reactions to prepare hyperbranched polymers is of great significance.In this work,trialdehydes,diamines,and trimethylsilyl cyanide could easily undergo multicomponent polymerization under mild conditions,producing hyperbranched poly(α-aminonitrile)s with high molecular weights(M_(w) up to 4.87×10^(4))in good yields(up to 85%).The hyperbranched poly(α-aminonitrile)s have good solubility in commonly used organic solvents,high thermal stability as well as morphological stability.Furthermore,due to the numerous aldehyde groups in their branched chains,these hb-poly(α-aminonitrile)s can undergo one-pot,two-step,four-component post-polymerization with high efficiency.This work not only confirms the efficiency of our established catalyst-free multicomponent polymerization of aldehydes,amines and trimethylsilyl cyanide,but also provides a versatile and powerful platform for the preparation of functional hyperbranched polymeric materials.
Tian-Yu ChengJian-Qing DingYu-Xin TongJun-Guo FangJia Wang
Core-shell colloidal particles with a polymer layer have broad applications in different areas.Herein,we developed a two-step method combining aqueous surface-initiated photoinduced polymerization-induced self-assembly and photoinduced seeded reversible addition-fragmentation chain transfer(RAFT)polymerization to prepare a diverse set of core-shell colloidal particles with a well-defined polymer layer.Chemical compositions,structures,and thicknesses of polymer layers could be conveniently regulated by using different types of monomers and feed[monomer]/[chain transfer agent]ratios during seeded RAFT polymerization.
Some novel manganese and nickel complexes were synthesized by reacting manganese(II)dichloride and nickel(II)dichloride with pyridyl-imine ligands differing in the nature of the substituents at the imino nitrogen atom.All the complexes were characterized by analytical and infrared data:for some of them single crystals were obtained,and their molecular structure was determined by X-ray diffraction.The complexes were used in association with methylaluminoxane(MAO)for the polymerization of 1,3-butadiene obtaining active and selective catalysts giving predominantly 1,2 polybutadiene in case of manganese catalysts and exclusively cis-1,4 polybutadiene in case of nickel catalysts.
Giovanni RicciBenedetta PalucciSimona LosioAnna SommazziFrancesco MasiGuido PampaloniMassimo Guelfi
Practical Zn metal batteries have been hindered by several challenges,including Zn dendrite growth,undesirable side reactions,and unstable electrode/electrolyte interface.These issues are particularly more serious in low-concentration electrolytes.Herein,we design a Zn salt-mediated electrolyte with in situ ring-opening polymerization of the small molecule organic solvent.The Zn(TFSI)_(2)salt catalyzes the ring-opening polymerization of(1,3-dioxolane(DOL)),generating oxidation-resistant and non-combustible long-chain polymer(poly(1,3-dioxolane)(pDOL)).The pDOL reduces the active H_(2)O molecules in electrolyte and assists in forming stable organic–inorganic gradient solid electrolyte interphase with rich organic constituents,ZnO and ZnF_(2).The introduction of pDOL endows the electrolyte with several advantages:excellent Zn dendrite inhibition,improved corrosion resistance,widened electrochemical window(2.6 V),and enhanced low-temperature performance(freezing point=-34.9°C).Zn plating/stripping in pDOL-enhanced electrolyte lasts for 4200 cycles at 99.02%Coulomb efficiency and maintains a lifetime of 8200 h.Moreover,Zn metal anodes deliver stable cycling for 2500 h with a high Zn utilization of 60%.A Zn//VO_(2)pouch cell assembled with lean electrolyte(electrolyte/capacity(E/C=41 mL(Ah)^(-1))also demonstrates a capacity retention ratio of 92%after 600 cycles.These results highlight the promising application prospects of practical Zn metal batteries enabled by the Zn(TFSI)2-mediated electrolyte engineering.
Zhenjie LiuMurong XiRui ShengYudai HuangJuan DingZhouliang TanJiapei LiWenjun ZhangYonggang Wang
