High-performance all-polymer dielectric and electrical energy storage materials containing conjugated segment and multi-fluorinated pendants

[Display omitted] •Block copolymer containing multi-fluorinated segments was synthesized.•Block copolymer displayed dielectric constant of 8 and dielectric loss of 0.002.•Block copolymer exhibited energy density of 11.45 J cm−3 and efficiency of 99%. Highly polarizable block copolymer consisting of insulating polynorbornene and conductive polyacetylene segments with multi-fluorinated pendants was synthesized by tandem ring-opening metathesis polymerization and metathesis cyclopolymerization, which displayed relatively high dielectric constant of 8, very low dielectric loss of about 0.003, and enhanced energy density of 11.45 J cm−3 at the electric field strength of 450 MV m−1 accompanied with an excellent charge-discharge efficiency of 99%. The outstanding dielectric and energy storage capability were mainly attributed to high dipole moment of multi-fluorinated groups on polymer backbone and the interfacial polarization derived from the unique self-assembled nanostructure of block copolymers.