Perfluoro-1,10-decanedicarboxylic acid865-85-032 % similar Hexafluoropropylene-tetrafluoroethylene copolymer25067-11-232 % similar 1,5-Diethyl 2,2,3,3,4,4-hexafluoropentanedioate424-40-831 % similar 1,2-Dichlorotetrafluorocyclobutene-1377-93-530 % similar