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The data on the methods for the preparation of polyetherketones by electrophilic and nucleophilic methods are considered and generalized. It is shown that polyetherketones by electrophilic substitution are carried out as homopolycondensation aromatic monocarboxylic acids and their halides and polycondensation of polynuclear aromatic hydrocarbons with aromatic dicarboxylic acids or their halides, and phosgene in organic solvents (1,2-dichloroethane, methylene chloride, nitrobenzene and etc.) in the presence of Ziegler-Natt catalysts. However, this process has not found an industrial application in view of such disadvantages as low yield of the desired product, the formation of a polymer with low molecular weight, synthesis time (15-40 hours), the use of large amounts of catalyst, the complexity of polymer purification of it.

The effect of heating cycles of polyether ether ketone up to 420 °C on the thermophysical properties was studied by the method of differential-scanning calorimetry. It is shown that with each subsequent heating the glass transition temperature increases, while the melting and crystallization temperature decreases, which may indicate an increase in the molecular weight of the polymer due to the structuring processes. The main degradation products of polyether ether ketone in air at temperatures of 350-450 °C were determined by gas chromatography and thermal decomposition schemes were proposed.