摘要
以2-巯基苯并咪唑为配体,制备了一种新型稀土钐配合物.采用红外光谱、热重分析等方法研究了钐配合物对天然橡胶硫化胶热氧老化过程的影响,探讨了钐配合物对天然橡胶硫化胶防老化作用的机理.红外光谱分析结果表明添加2-巯基苯并咪唑钐配合物的天然橡胶硫化胶经热氧老化后,氧化产物的生成量明显减少.2-巯基苯并咪唑钐配合物对天然橡胶硫化胶有显著的防老化作用,其防老化效果优于防老剂MB和防老剂4010NA.2-巯基苯并咪唑钐配合物通过结构中的硫醚键分解氢过氧化物,另一方面稀土钐离子与老化过程中产生的含氧自由基作用,使其失去反应活性,从而达到了较好的防老化效果.分别采用Kissinger和Flynn-Wall-Ozawa方法计算出了添加不同防老剂天然橡胶硫化胶的热氧化活化能,结果表明添加钐配合物天然橡胶硫化胶的热氧化活化能高于添加防老剂MB和添加防老剂4010NA硫化胶的热氧化活化能值.
A novel kind of Sm（Ⅲ） complex with 2-mercaptobenzimidazole was prepared. The antioxidative properties and mechanism of the Sm （Ⅲ） complex in the natural rubber （NR） vulcanizates was investigated by attenuated total-reflectance Fourier transform infrared （FTIR-ATR） spectroscopy and thermogravimetric analysis. The thermo-oxidative stability of the NR vulcanizates was found to be improved markedly by the addition of the Sm（Ⅲ） complex. The FTIR-ATR results showed that the Sm（Ⅲ） complex retarded aging and allowed the oxidation products to increase more slowly. The Sm（Ⅲ） complex had no effect on the thermal decomposition of the NR vulcanizate, but it improved the thermo-oxidative stability significantly. The antioxidant effect of the Sm （Ⅲ） complex was superior to that of antioxidant MB and antioxidant 4010NA. It could be attributed to the thioether bonds which can decompose the hydroperoxide and the Sm（Ⅲ） ions which can capture and inactivate the oxy radicals. The apparent thermo-oxidation activation energy （E） of the NR vulcanizates was calculated by the Kissinger and Flynn-Wall-Ozawa methods,respectively. The results showed that the NR vulcanizate with the Sm（Ⅲ） complex had higher thermo-oxidation activation energy than that of the samples with antioxidant MB and antioxidant 4010NA.
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
2011年第3期320-326,共7页
Acta Polymerica Sinica
基金
国家高技术研究发展计划(863计划
项目号2009AA03Z338)
国家自然科学基金(基金号51003031)资助项目
关键词
钐配合物
2-巯基苯并咪唑
天然橡胶
防老剂
机理
动力学
Sm（Ⅲ） complex, 2-Mercaptobenzimidazole, Natural rubber, Antioxidant, Mechanism, Kinetics
