ANTIOXIDANT PROPERTIES OF THE FOMITOPSIS PINICOLA TRUNE EXTRACT IN THE COMPOSITION OF POLYETHYLENE FILMS

Scientific literature shows that the thallus of Fomitopsis pinicola is sufficiently rich in secondary metabolites with pronounced antioxidant properties. However, the experiments showed that ethanol extracts of F. pinicola compared with extracts of higher plants (for example, Chelidonium majus) were characterized by low antioxidant properties, both in the polymer composition and according to biochemical analysis. The induction period of oxidation of polyethylene films with extracts of F. pinicola was 3.25 times lower than the induction period of oxidation of similar polymer films with C. majus extracts. It is assumed that this result is a consequence of the presence of most phenolic compounds of F. pinicola within melanins. In the composition of these pigments, phenolic compounds are sedentary and cannot diffuse in the polymer melt. In addition, a number of reactive functional groups will not exhibit their antioxidant properties because of spatial difficulties. Extraction conditions (extractant, time), under which the obtained F. pinicola extracts confirm high antioxidant properties in polyethylene films, significantly exceeding the antioxidant properties of C. majus extracts, were experimentally determined during the studies. It is shown that to obtain highly effective antioxidant F. pinicola extracts for polymer stabilization it is most rational to use acetone as an extractant. The recommended extraction time is at least 5 days.