The authors have studied certain regularities in the three-dimensional polycondensation of oligomeric ether acids with the common formula C[CH2OC(O)(CH2)nCOOH]4, wheren= 2, 4, 8, with tri-and tetratomic silicoorganic alcohols, various glycols, and diamines. Problems have been considered relating to gel formation in systems containing oligomeric and monomeric branching units. The parameters obtained, which characterize gel formation in oligomeric systems, were compared with the values calculated in conformity with Flory's theory. Research was also carried out on the kinetic regularities of three-dimensional condensations of oligomers, and constants were calculated for the rates of esterifications and the rates of formation of the gel fraction. The thermomechanical properties of polymers were investigated during the condensation processes.