Patent ID: 6998464

Claim:
A method of preparing a solution of a polymer comprising recurring azole units, which comprises dissolving a sufficiently dried polymer comprising recurring azole units of the formula wherein the radicals Ar, Ar 1 and Ar 2 are tetravalent, divalent or trivalent aromatic or heteroaromatic groups and the radicals X, which are identical within a repeating unit, are each an oxygen atom, a sulfur atom or an amino group bearing a hydrogen atom, a group having 1–20 carbon atoms, in N,N-dimethylacetamide having a sufficiently low water content at a temperature of 250° C. or less under an inert gas atmosphere, wherein a sufficiently dried polymer comprising recurring awls units of the formula (1) or (2) of which 90% by weight based on the total weight of the polymer comprising recurring azole units has a particle size of less than 1 mm is used.