新型稀土防老剂的合成及对天然橡胶防护性能的研究

摘要

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-hydroxyphenyl) propionic acid to La(NO3)3 · H2O 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.%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,制备一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一种配合物.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.