. . . . . "a gaseous hydrocarbon C4H6; used in making synthetic rubbers"@en-us . . "114912092"^^ . "0"^^ . . "110700693"@en-us . "butadiene"^^ . "14912092-n"^^ . "a gaseous hydrocarbon C4H6; used in making synthetic rubbers"@en-us . . "butadiene"@en-us . . . "0"^^ . "114063840"@en-us .