新型稀土防老剂的合成及对天然橡胶防护性能的研究

以3-（3，5-二叔丁基-4-羟基苯基）丙酸、La（NO3）3·H2O和氢氧化钠为原料，制备-种新型稀土橡胶防老剂。并采用红外光谱、热重分析及荧光测试对合成的防老剂结构进行表征，结果表明合成的防老剂为稀土镧与3-（3，5-二叔丁基-4-羟基苯基）丙酸配体中羰基配位得到的-种配合物。优化后得到稀土防老剂最佳合成实验条件：3-（3，5-二叔丁基-4-羟基苯基）丙酸与硝酸镧物料物质的量比为2：1，回流时间6h。采用力学性能测试、红外光谱、热重分析等方法研究了稀土防老剂对NR硫化胶的防护性能。结果表明，防老剂对NR硫化胶具有显著的防老化作用，其防老化效果优于市售酚类BHT防老剂，与胺类4010NA防老剂相当，且对橡胶无色泽污染性。

Synthesis of a Rare Earth Antioxidant and Its Anti-Aging Properties for Natural Rubber Vulcanizates

The rare earth antioxidant was synthesized with 3-（3, 5-di-tert-butyl 4 hydroxyphen-yl） propionic acid and lanthanum nitrate as raw materials. The antioxidant characterized by infrared spectroscopy, thermal analysis and fluorescence, was La complex. And the optimal synthesis conditions were as follows： the molar ratio of 3-（3,5-di-tert-butyl-4-hydroxyphen- yl） propionie acid to La（NO3 ）3 ~ H20 2 ： 1 and reflux time 6 h. The effects of rare earth antioxidant on the protective effect of NR vulcanizates were studied by mechanical property testing, infrared spectroscopy, thermal analysis. These results show that rare earth antioxidant had pronounced anti-aging properties, which is higher than those of BHT antioxidant and equal to those of 4010NA. Besides, the synthesized rare earth antioxidant had no color pollution for rubber.