Two theoretical models are proposed to describe rearrangement mechanisms for supermolecular structures of oligomeric liquids. The first is based on the concept of associate-size distribution, varying with the addition of molecules to the associates. These molecules are activated by external action. The other model takes into account the fact that after activation, the equilibrium size distribution function is attained by way of an activated molecule redistribution between associates, owing to "cleavage-addition." Within the framework of accepted restrictions, the analytical solutions were obtained adequately to describe rheological and relaxation relationships revealed for various types of oligomeric systems.