new crosslinked 1 , 2 , 4 - oxadiazole elastomers have been prepared by thermally condensing monomer having the formula h 2 nc - r - q , wherein q is a triazine ring - forming group such as nitrile or amidine , or a mixture of said monomer with rnh 2 ] 2 , with r in these formulas standing for a bivalent organic radical having the formula --. sub . p --, or -- cfy . sub . m o . sub . p o n cfy -- wherein x is fluorine or hydrogen , y is fluorine or trifluoromethyl , p ranges from 1 to 18 , and m + n ranges from 2 to 7 . in the monomer charge , the overall proportions of amidoxime groups to triazine ring - forming groups varies depending on the extent of crosslinking desired in the final polymer . the heat and chemical resistant elastomers disclosed can serve , for instance , as adhesives , caulking compounds , channel sealants , fuel tank liners .