https://doi.org/10.1351/goldbook.T06260
The formation of an addition oligomer, having uniform end groups X' ... X" , by a chain reaction in which a chain transfer limits the length of the polymer ('telomer') produced. An example is the polymerization of styrene in bromotrichloromethane solution (X' = CCl3, X" = Br), where Cl3C· radicals are formed in the initiation step to produce Cl3C[CH2CHPh]nBr, with greater than 1 and often less than ca. 10: 

See also: oligomerization