Study On PVC And PP Used In Electron Beam Irradiation Sterilization

This paper choose hindered phenol antioxidant, Irganox 1010, Irganox 1076, Irganox 168, blue toner and the paired to modify PVC irradiation resistant yellow, choose antioxidant Irganox 1010, Irganox 1076, Irganox 168, light stabilizer Tinuvin 622, Tinuvin 770, Chimassorb 944 and its combination to modify PP resistant to radiation yellowing. The following conclusions are obtained:(1) PVC added irganox 1010,irganox 1076 singlely and the combination of antioxidants has certain inhibition of yellowing effect, whose mechanical properties have a certain degree of improvement. When PVC added antioxidant 1010 of 2phr, the transmittance of PVC was 73.1, and the haze was 23.6.(2) On the base of PVC added antioxidant 1010 of 2phr, we add blue toner of lphr, whose yellowing index is less than 1.5 under the doses of 25 kGy,30 kGy and·even higher, The transmittance is 76.32, the haze is 13.58, and the optical performance is good.(3) PP material added antioxidant 1076 for 1.5 and 2 copies shows good resistance to yellowing effect of irradiation, whose yellowing index is less then 1. The mechanics and optical performance of materials are good. PP added tinuvin 770 also shows resistance to irradiation induced color. When PP added tinuvin 770 of 0.5phr, the yellowing index is -1.09,which is minimum.(4) When PP material added the compound of antioxidant and light stabilizer, only antioxidant 1076 and light stabilizer 770 compound makes materials irradiated yellow index decreased, whose anti yellowing effect are less than single formula, indicating that antioxidants and light stabilizers in yellowing resistance show no obvious synergistic effect.(5) When PP added Irganox 1076, Irganox 168, tinuvin 622, tinuvin 770 and chimassorb 944, crystallinity improved. Crystallinity were higher than that of before irradiation when added antioxidants and tinuvin 770, which shows that antioxidant added to promote crystalline ascension. Tinuvin 622 and chimassorb 944 caused the drop of crystallization.(6) PP added irganox 1010, iraganox 168 and the light stabilizers have higher epitaxial initiation temperature. The epitaxial initiation temperature of PP added various antioxidants and light stabilizers decrease after irradiation, which is due to the degradation of the molecular structure caused by electron beam energy.