A method for carrying out homogenous polymerization reactions in a reactor, wherein monomers and/or prepolymers are fed (apportioned). In a first step, an initiator is optionally admixed with the monomer and/or prepolymer. In a second step, once viscosity is substantially higher, a solvent is added thereto and/or the monomer itself is partially evaporated, it is condensed externally and/or internally and fed back into the reactor.