Molecular weight characteristics of polyetheretherketone (PEEK): analysis of determination conditions

Polyetheretherketone (PEEK), which is highly resistant to aggressive media and various types of radiation, is widely used in various industries. At the same time, the information on the molecular weight characteristics of PEEK, which is necessary for the creation of polymer materials with specifi ed properties, is quite limited. Determination of these characteristics is complicated by the almost complete insolubility of PEEK in organic solvents. The work is devoted to the analysis of the applicability of viscometry, determination of the melt fl ow index and gel permeation chromatography (GPC) for assessing the molecular weight characteristics of PEEK. The preliminary modifi cation of the polymer to transform it into a soluble state has been considered as an alternative approach. A GPC-method of the determination of molecular mass of sulfonated PEEK has been developed. The values of average molecular weights for samples produced by Petrov Institute of Plastics and a commercial sample Victrex 150G were determined. Good agreement of the GPC data with the results of determining the melt fl ow index of the polymer makes it possible to consider the latter as an express method for assessing the molecular weight of a polymer.

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