Analysis of Intermediates Produced During the Synthesis of Alkyd Resins

The paper considers the possibility of using the FT-IR spectroscopy method in the production of alkyd varnishes and resins to control various stages of synthesis. A number of samples were analyzed at different stages of synthesis, selected under production conditions at the stages of transesterification and polycondensation. The formulation of pentaphthalic resin is presented, the chemistry and features of obtaining alkyd resins are analyzed. Having considered the issues of express control of the production of alkyd varnishes, the possibility of controlling the studied stages by infrared spectra in the laboratory was investigated and analyzed. It has been established that the IR spectra of samples taken sequentially during the synthesis can be used to control the course of the chemical reaction of polycondensation in the technological process. Control can be carried out according to three main absorption bands, taking into account the identified patterns observed in the synthesis process: stretching vibrations—OH; C–H stretching vibrations of olefins (oils) and arenes (phthalates); valence antisymmetric and symmetric C–H methyl and methylene groups; bending vibrations of four aromatic ring hydrogens.