A　series　orange　phosphorescent　copolymers　with　platinum(II)　polymetallayne-based　backbone　have　been　successfully　prepared　through　Sonogashira　cross-coupling　among　bicarbazole　moieties,　2-(naphthalen-2-yl)pyridine-based　Ir-III　phosphorescent　units,　and　trans-[PtCl2(PBu3)(2)].　The　photophysical　investigations　have　indicated　highly　efficient　energy-transfer　from　both　the　singlet　and　high　energy　triplet　states　from　the　polymetallayne　segments　to　the　phosphorescent　units　in　the　copolymer　backbone　due　to　the　proper　energy-level　matching　fulfilled　by　the　2-(naphthalen-2-yl)　pyridine-type　ligands　in　the　Ir-III　phosphorescent　units.　Benefiting　from　these　advantages,　the　phosphorescent　polymers　can　furnish　solution-processed　phosphorescent　OLEDs　(PHOLEDs)　with　high　EL　efficiencies　with　current　efficiency　(eta(L))　of　8.35　cd　A(-1),　external　quantum　efficiency　(eta(ext))　of　3.79%　and　power　efficiency　(eta(P))　of　2.25　lm　W-1,　representing　the　very　decent　electroluminescent　performances　ever　achieved　by　the　orange　phosphorescent　copolymers.　This　work　herein　might　not　only　provides　a　further　study　about　the　novel　phosphorescent　copolymers　with　platinum(II)　polymetallaynes　as　backbone,　but　also　provide　valuable　information　for　the　design　and　synthesis　of　highly　efficient　phosphorescent　copolymers.　(C)　2015　Elsevier　B.V.　All　rights　reserved.