The structure and properties of multicomponent copolymers were studied using an approach developed previously for the analysis of linear polymers. Equations were derived that describe the effect of composition on the physical characteristics of the copolymers, including the density, the glass transition temperature, the temperature of the onset of intense chemical degradation, index of refraction, and the stress-optical coefficient. These resulting equations were used to calculate the characteristics of five multicomponent copolymers. Copolymers containing up to five components were synthesized on the basis of MMA, butylmethacrylate, butylacrylate,nonylacrylate, 2-ethlylhexylacrylate, and heptylacrylate.