The effects of three antioxidants on aging properties of raw trans-1,4-poly(butadiene-co-isoprene)copolymer rubber(TBIR),curing charac-teristics of natural rubber(NR)/TBIR rubber com-pounds,and physical and mechanical properties and flexural fatigue resistance of NR/TBIR vulcanizates were studied.The results showed that different types of antioxidants had different anti-aging effects on raw TBIR and NR/TBIR composites.The oxidation in-duction temperature and oxidation induction time of raw TBIR containing different antioxidants were dif-ferent,and the oxidation induction temperature was the highest of raw TBIR containing hindered pheno-lic,p-phenylenediamine and phosphite composite antioxidant and the oxidation induction time was the longest,and the thermal-oxidative aging resistance was the best.Compared with NR compound,the minimum torque of different NR/TBIR compounds all increased to varying degrees,the scorch time were prolonged,the vulcanization time were shor-tened and the vulcanization rate were accelerated,and the vulcanization rate of the compound contai-ning composite antioxidant was faster than that of the other NR/TBIR compounds.The types of antioxi-dants had no significant effect on the physical and mechanical properties and room-temperature flexural fatigue resistance of NR/TBIR vulcanizates.Compared with the NR vulcanizate,the tensile strength,modulus,and elongation at break of the NR/TBIR vulcanizates were slightly lower,the abra-sion resistance was significantly improved,while the rolling resistance was significantly reduced;com-pared with NR vulcanizate,except for NR/TBIR vul-canizate containing hindered phenolic antioxidant,the aging coefficients of the other vulcanizates all re-duced;compared with NR vulcanizate,the room temperature fatigue life of NR/TBIR vulcanizates were significantly prolonged and the high-tempera-ture fatigue life at 90℃ all extended to varying de-grees,and the vulcanizate containing only hindered phenolic antioxidant had the longest fatigue life;after aging at 100℃ for 48 h,the grade 6 fatigue life of NR/TBIR vulcanizate containing only hindered phe-nolic antioxidant was significantly prolonged,while the fatigue life of the other NR/TBIR vulcanizates and NR vulcanizate remained basically unchanged.Overall,hindered phenolic antioxidant had a good thermal-oxidative aging protection effect on NR/TBIR vulcanizate.
维普
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