Preparation Of Vitamin C Rare Earth Complex And Its Anti-aging Application In Natural Rubber

It is a practical project to improve the service life of rubber products and significant to develop novel high performance,environmental friendly antioxidants.One novel complex of lanthanum(La) with vitamin C was synthesized and characterized by fourier transform infrared spectroscopy(FTIR),13C nuclear magnetic resonance(13C NMR),X-ray diffraction,thermal analyses and elemental analyses. The composition of the complexe is suggested as La(C6H7O6)3·3H2O. The complex was mixed with matrixes of natural rubber(NR) and natural rubber/carbon black(NR/CB). The antioxidative properties and mechanisms of lanthanum complex in the NR vulcanizates and NR/CB vulcanizates were investigated and its antioxidative effect was compared with that of antioxidant MB, RD and 4010NA.It was found that NR vulcanizates and NR/CB vulcanizates with La complex with vitamin C had a high mechanical strength retention. FTIR spectra indicated that La complex with vitamin C caused the decrease of thermal oxidation products in both vulcanizates. Thermal analyses results showed that La complex with vitamin C had no influence on thermal degradation temperature of NR vulcanizates and NR/CB vulcanizates.Through the ultraviolet aging and ozone aging testes, it was concluded that La complex with vitamin C enhanced the ability of NR vulcanizates and NR/CB vulcanizates to resist ultraviolet and ozone aging. Optical microscopy results showed that La complex with vitamin C resisted the development of cracking on the NR vulcanizates and NR/CB vulcanizates surfaces during ultraviolet and ozone aging process.In addition, it can be known through Akron abrasion and fatigue ageing testes that La complex with vitamin C reduced the Akron abrasion volume of NR vulcanizates and NR/CB vulcanizates and slightly improved the fatigue life of both vulcanizates.