Photodegradation of polylactide with phenol and aniline terpene derivatives additives

The article is devoted to the development of new photostabilizers of polylactide, a polymer that is an environmentally friendly alternative to fossil-based polymers. The new photostabilizers are designed to extend the life of products when exposed to ultraviolet radiation and maintain the performance of the polymer when recycled. Photostabilizers 2-isobor-nylphenol and N-para-mentenaniline were obtained while the available natural monoterpene camphene alkylation of phenol or aniline. Irradiation of polylactide samples with a photostabilizer was carried out by radiation with 253,7 nm wavelength for 4 h. The effectiveness of the photostabilizer was evaluated on the basis of IR spectrometric data, as well as by scanning electron microscopy and simultaneous thermal analysis. The introduction of each of the selected stabilizers at the concentration of 0.05% by weight resulted in the protection of ester bonds between the monomer units of the polymer. However, 2-isobornylphenol was more effective. The IR spectra analysis of the irradiated samples revealed a 15% decrease in the absorption intensity of the characteristic bands of the ester groups in the sample with 2-isobornyl-phenol, 46% in the sample with N-para-mentenaniline, and 50% in the sample without stabilizer addition. Thus, the use of 2-isobornylphenol as a photoprotective additive will extend the service life of polylactide plastic products under exposure to aggressive UV-C radiation. The protection of polylactide from UV radiation opens up prospects for expanding the areas of application of polylactide, a polymer synthesized from renewable raw materials.