Chemiluminescence study on the radiochemical stability of polypropylene modified with microalgal extracts

Highlights: • Microalgal extracts are proper stabilizers in irradiated polypropylene. • The stability of PP is higher by Spirulina platensis than by Chlorella vulgaris. • The high dose does not diminish the protection activities of studied additives. • Chlorella vulgaris and Spirulina platensis protect PP by high activation energies. The stabilization effects of Chlorella vulgaris (Ch) and Spirulina platensis (Sp) powders on polypropylene (PP) are investigated by isothermal and nonisothermal chemiluminescences on the degrading samples by γ-irradiation. The antioxidative protection activities were evaluated on PP containing 1 wt% additive. The antioxidant characteristics on these microalgae are discussed in respect with the progress of oxidation after γ-exposure at 25, 50 and 100 kGy. The degradation protectors Chlorella vulgaris and Spirulina platensis are efficient stabilization agents even at high doses, when the effectiveness of Spirulina platensis exceeds the effects induced by Chlorella vulgaris. The activation energies required to the delay of oxidation were calculated at various radiolysis degrees. The degradation achieved by thermal or radiochemical ageing is hindered by the polyphenols, which are biocompatible with human body. The contributions of the studied natural additives may be considered as a proper solution for the protection of polymers subjected to radiation sterilization or processing. The present study proposes optimal conditions for application of algal extracts in the food handling and medical wear.