Preparation Of Lanthanum Sullfanilate And Its Application In Rubbers

With the rapid development of rubber industry in recent years, consumptions of rubber material are also increasing gradually. Meanwhile, people’s awareness of environmental are also enhanced. Therefore, the research and development of a new environmental friendly, low cost, efficient and multi-functional antioxidant will play an important theoretical and practical role in the development of rubber industry and rubber products.In this paper, a new kind of rare earth complex, lanthanum sulfanilate (LaS), was synthesized and characterized by IR spectra, elemental analyses and X-ray photoelectron spectroscopy. The results indicated that the composition of the rare earth complex is: C12H12S2O8N2La·2H2O, The structural formula is as follows:Firstly, the rare earth complex as an antioxidant was added to natural rubber (NR) and styrene-butadiene rubber (SBR) compounds, compared to antioxidant RD, MB and4010NA. It was found that the rare earth complex would delay the rubber vulcanization time, on the basis of no color pollution to rubber products, the rare earth complex shows a good thermo-oxidative aging resistance effect. The mechanical properties and their retention of NR vulcanizates with rare earth complex after thermo-oxidative aging are superior to those of the vulcanizates with antioxidants RD and4010NA. The rare earth complex can not only improve the mechanical properties of SBR vulcanizates, but also show a good thermo-oxidative resistance effect in comparison with antioxidants4010NA and MB.The thermal analysis results showed that the rare earth complex improved rubber’s stability of thermal and thermal oxidative aging. And XPS, NMR crosslinking density measurement results showed that the rare earth complexes not only can capture free radicals, prevent C-O and C=O groups generated, but also can prevent the rubber compounds excessive crosslinking and hardening.At the end of the dissertation, the rare earth complex as an aid-antioxidant compounded with antioxidants4010NA, MB and RD in different ratios. It was found that compounded antioxidants could apparently accelerate the vulcanization of SBR compounds. Under somecompounding proportions, vulcanization efficiency of SBR is better than that of singleantioxidants.Through the thermo-oxdative aging and ultraviolet aging test, it was found that thecompounded antioxidants show a good synergistic effect. The mechanical properties and theirretentions of SBR vulcanizates with compounded antioxidants after thermo-oxidative agingand ultraviolet aging are superior to those of the vulcanizates with single antioxidantscompounds.