The invention concerns copolymers of terpenes without conjugated double bond and vinyl compounds and/or dicarboxylic acids with a C-C double bond and their derivatives as comonomers. They are preferably prepared in a radical mass polymerisation process at a temperature of 100 to 200 DEG C within 1 to 10 hours. Owing to the absence of solvents or thinners, particularly pure copolymers are obtained. They are suitable in particular as tackifiers.
