The invention relates to the use of functionalized perylene-3,4,9,10-tetracarboxylic acid diimides as initiator and/or co-reactant for polymerization reactions, to polymers prepared using the perylene-3,4,9,10-tetracarboxylic acid diimide compounds, to the use of these colored and/or fluorescent polymers, and to novel functionalized perylenetetracarboxylic acid diimides.