Unperturbed dimensions of linear chain polymers in pure and in mixed solvents

The unperturbed dimensions of poly (p-tert-butylphenylmethacrylate) and of poly (p-tert-butylcyclohexyl-methacrylate) have been determined from intrinsic viscosity in pure and mixture of solvents by using the semiempirical equation of Stockmayer and Fixman. This dimensions may vary widely depending upon the specific molecular interaction for the case of pure solvents and on the excess thermodynamic properties for the case of mixture of solvents. The results obtained are in agreement with the behaviour of other polymers already reported in the literature.