NEW MATERIAL:A fluorine-containing guanamine compound of formula I (R is 1-18C alkyl, allyl, cyclohexyl, phenyl; n is 1 to 8).

EXAMPLE: 2,4-Diamino-6-(ωH-perfluoroethyl)-S-triazine.

USE: Polymerizable monomer, starting substance for a variety of fluorine- containing compounds. There scarcely happen the elimination of fluorine- containing groups by hydrolysis, heat or light, thus the functions of the compound is maintained for a long period of time, thus they are used in the production of fluorine-containing polymers used as rubber materials, mold lubricants, water repellents or oil repellents, optical materials, heat-resistant resins or medicines.

PREPARATION: The reaction of a fluorine-containing compound of formula II (X is residual group remaining after removing active hydrogens from a hydroxy compound, halogen or amino) with biguanide, N-substituted biguanide or their hydrochlorides in a non-aqueous polar solvent such as methanol, if necessary, in the presence of a basic compound to obtain the compound of formula I.