A study of polymer materials using a modified method of analytical pyrolysis

Among the methods that allow the study of polymer materials, the method of pyrolytic gas chromatography is widely used. The current regulatory documentation for research using this method applies only to rubber mixtures, rubbers and rubber products. In addition, a number of organic compounds and polymers cannot be analyzed by this method due to the lack of detectable pyrolysis products. Compounds containing polar functional groups (for example, hydroxyl, carboxyl) often cause problems when studied by this method due to their thermal lability and interaction with the stationary phase of the chromatographic column. This problem can be solved by derivatization of samples: the resulting volatile derivatives are usually more thermally stable and less polar, as a result of which the separation of components during chromatography is improved, it becomes possible to qualitatively analyze microquantities of a substance, and most importantly, it becomes possible to study a number of organic compounds and polymers. Classical methods of pre-derivatization (silylation, alkylation, acylation) involve adding a derivatizing agent to the analyte and then maintaining the mixture for the time necessary to complete the derivatization process. This article is devoted to the identification of certain types of polymers, including condensation polymers that do not form thermally stable pyrolysis products, using a modified method of analytical pyrolysis with derivatization of pyrolyzate components with tetramethylammonium hydroxide (TMAH) in situ. A comparative analysis of gas chromatographic studies of pyrolysates of objects with and without TMAH derivatization was carried out. The advantages of the proposed method are shown on products of various types containing polymeric substances, general approaches to preparing samples for research by this method, and features of interpretation of the resulting chromatograms are presented.