Abstract
Abstract The study of the peculiarities of the phase behaviour of solutions of poly(amic acids) (PAA) on the basis of low‐active dianhydride of tricyclodecentetracarboxylic acid in dioxane permitted to establish the conditions of their existence in the mesomorphic state. Under these conditions an intensive growth of the PAA chains was observed, the polymerization degree increased from 7 up to 90, and the intrinsic viscosity of the polymers increased from 0.1 up to 1.2 dl/g.