The specific refractive index increments of polyisoprenes in various solvents

Abstract

Specific refractive index increments of polyisoprenes with high cis-1,4 content have been determined in six solvents at 20º and λ 546 nm. A linear relationship was found between the refractive index increment dn/dc = n and the refractive index of the solvent n_l : N₄₅₆²⁰ = 1.687 - 1.105n₁ The results are compared with the best values reported for natural rubber which are usually employed for polyisoprene in light scattering measurements.