In　this　paper,　the　fluoro-polymer-coated　multiwall　carbon　nanotubes　(MWCNTs)　were　prepared　by　in　situ　atom　transfer　radical　polymerization　of　2-(perfluoroalkyl)　ethyl　methacrylate　(FEMA)　on　the　surface　of　MWCNTs.　Scanning　electron　microscopy　results　showed　that　the　fluoro-polymer　on　MWCNTs　surface　improved　the　dispersion　and　compatibility　of　MWCNTs　in　the　poly(vinylidene　fluoride)　(PVDF)　matrix.　The　PFEMA@MWCNTs/PVDF　composites　exhibited　improved　thermal　stability　and　reduced　crystallinity　due　to　enhanced　interface　strength　between　MWCNTs　and　PVDF.　Furthermore,　nearly　100%　polar　phase　PVDF　formed　after　introducing　high　PFEMA@MWCNTs　content　into　PVDF　matrix.　It　was　also　found　that　PFEMA@MWCNTs-filled　PVDF　composites　present　advantages　in　increasing　dielectric　constants　and　decreasing　loss　tangents　due　to　the　restriction　of　interface　polarization　and　leakage　current.　Based　on　the　percolation　threshold　and　ac　conductivities,　the　PFEMA@MWCNTs/PVDF　composites　exhibit　good　insulation　properties　and　are　promising　for　high-performance　dielectric　composite　applications.　©　2019,　Springer　Science+Business　Media,　LLC,　part　of　Springer　Nature.