摘要 |
<p>1. Perfluoroalkanes and haloperfluoroalkanes of general formula: <CHEM> wherein: a and c, equal to or different from each other, are integers ranging from 0 to 4 and preferably from 0 to 2, and their sum is not lower than 1 and not greater than 6, preferably not greater than 3; b is an integer ranging from 1 to 5, preferably from 1 to 3; the sum a+b+c is not greater than 8, and preferably not greater than 5; X and Y, equal to or different from each other, can be iodine, bromine, chlorine or fluorin; with the limitations: that X and Y can be contemporaneously fluorine only in case in which at least one of the two indexes a and c is equal to or greater than 2; that X is not fluorine when a = 1 and c = 0; that Y is not fluorine when c = 1 and a = 0; that Y cannot be I when X = F and c = 0; that X cannot be I when Y = F and a = 0; the -C2F4- units can be present in the molecular structure also alternated to the -CF2-CF(CF3)- units; are prepared by telomerizing with C3F6 or with a mixture of C3F6 + C2F4 a precursor constituted by one or more -CF2CF2- units, and having at one end a iodine atom, and at the other end a halogen atom selected from iodine, chlorine, bromine, fluorine, and in the possible subsequent halogenating reaction with fluorine, chlorine, bromine for the substitution of iodine atoms. </p> |