With　the　rapid　advancement　of　5G　communication　technology,　the　development　of　novel　low-dielectric　constant　polyimides　(PIs)　as　interlayer　dielectric　materials　has　become　a　key　area　of　research.　However,　the　development　of　fluorinated　diamines　with　simple　synthetic　routes　remains　a　challenge.　In　this　study,　a　facile　and　efficient　one-step　synthetic　strategy　was　employed　to　construct　three　novel　fluorinated　diamines　with　fully　non-planar　and　twisted　structures.　The　influence　of　fluorine　content　and　different　bulky　side　groups　on　the　dielectric,　thermal,　and　optical　properties　of　the　PIs　based　on　these　diamines　was　investigated.　Notably,　the　increase　in　fluorine　content　and　structural　non-planarity　significantly　enhanced　the　dielectric　properties　and　moisture　resistance.　Among　the　synthesized　PIs,　FPOPF-6FDA　exhibited　the　most　favorable　performance,　with　a　low　dielectric　constant　(Dk　=　2.20　@　108　Hz),　low　dissipation　factor　(Df　=　0.00755　@　108　Hz),　low　water　absorption　(WA　=　0.89　%),　and　high　hydrophobicity　(WCA　=　93.90°).　Moreover,　the　non-planar　and　twisted　fluorinated　diamines　did　not　compromise　the　thermal　stability　(Td5　＞　500　°C,　Tg　=　250.87–340.13　°C),　optical　transparency　(T500　＞　85.90　%),　or　solubility　in　organic　solvents　of　these　PIs.　This　work　provides　valuable　insights　into　the　molecular　design　and　cost-effective　synthesis　of　high-performance　low-dielectric　PIs.　©　2025　Elsevier　Ltd