One important approach to access safe and high-energy batteries is to develop Li metal-based high-voltage batteries with a solid polymer electrolyte (SPE). However, it is notably difficult to construct such systems owing to the simultaneous occurrence of dendrite formation on the Li anode and severe oxidative decomposition against high-voltage cathodes. We here synthesize a new family of main-chain fluorinated solid polymer electrolytes (MCF-SPEs) that are compatible with both Li metal and high-voltage cathodes. Taking advantage of the synergistic weakly solvating capability and outstanding stability of the fluoropolymer, the electrochemical window is increased to 5.3 V, showing significantly mitigated dendrite proliferation and enhanced compatibility with various cathodes, including LiNi0.6Co0.2Mn0.2O2, LiCoO2, LiNi0.8Co0.1Mn0.1O2, etc. The unique solvation structure between MCF-SPEs and Li+ is probed to elucidate fundamental effects of fluoropolymers at electrode/electrolyte interfaces. Additionally, systematic study of varied fluorinated segment lengths that afford different contact ion pairs/ion aggregate solvation structures can guide further development of high-performance SPEs.

Polyethylene (PE) is the most heavily used polymer worldwide. Considerable efforts have focused on modifying properties of PE via cross-linking. In contrast to previous crosslinking methods, which generate PE thermosets of low processability, here, we report the development of a dynamic covalent networking additive (DCNA) that possesses the PE backbone and reconfigurable network with alkyl boronic esters as novel dynamic linkages. The addition of DCNA at 5 wt % provides PE materials with clearly improved mechanical (e.g., tensile strength, Young's modulus, and yield strength) and rheological (e.g., creep resistance) properties at elevated temperatures. Moreover, the obtained materials could be easily reprocessed, recycled, and 3D-printed, creating opportunities toward sustainable and high-performance PE materials.

Polymers with regulated alternating structures are attractive in practical applications, particularly for main-chain fluoropolymers. We for the first time enabled controlled fluoropolymer synthesis with alternating sequence regulation using a novel fluorinated xanthate agent via a light-driven process, which achieved on-demand copolymerization of chlorotrifluoroethylene and vinyl esters/amides under both batch and flow conditions at ambient pressure. This method creates a facile access to fluoropolymers with a broad fraction range of alternating units, low dispersities and high chain-end fidelity. Moreover, a two-step photo-flow platform was established to streamline the in-situ chainextension toward unprecedented block copolymers continuously from fluoroethylene. Influences of structural control were illustrated with thermal and surface properties. We anticipate that this work will promote advanced material engineering with customized fluoropolymers.

PBST and PBST/CDP nanofibrous membranes were prepared for the first time. PBST/CDP membranes were fabricated by means of in situ polymerization. The morphologies of membranes were dependent on the CDP content. PBST/CDP membranes exhibited excellent adsorption capacity.

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