Process for preparing long-chain polymethylene halide telomers

A process comprising combining in a batchwise, semi-continuous, or continuous manner, or a combination thereof, in the presence of at least one free radical initiator selected from azo compounds, peroxides, peresters, and mixtures thereof, under substantially oxygen-free conditions, and at a temperature from 75° C. to 125° C., (a) at least one telogen selected from (1) the class of fluoroalkyl halides that is represented by the following general formula:

• R′CH(R)X (1)
• wherein R′ is a fluoroalkyl or perfluoroalkyl group of 1 to 25 carbon atoms that optionally comprises at least one non-fluorine heteroatom;
• R is hydrogen or a perfluoroalkyl group of 1 to 6 carbon atoms;
• and X is iodine or bromine;
• and (2) the class of perfluoroalkyl halides that is represented by the following general formula:
• R′″CF(R″)X (II)
• wherein R′″ is a perfluoroalkyl group of 1 to 25 carbon atoms that comprises at least one non-halogen heteroatom;
• R″ is fluorine or a perfluoroalkyl group of 1 to 6 carbon atoms;
• and X is iodine or bromine;
• and (b) ethylene;
• said telogen and said ethylene being combined in total amounts such that the number of moles of ethylene per mole of telogen is at least 8.