【摘要】 本文用IR、ESR、NMR及力学性能的测定研究了受阻胺光稳定剂Tinuvin-770(T-770)对紫外光的防护行为。结果表明,该光稳定剂有一个浓度的最佳值(0.3％W/W)。当多于或少于0.3％时,其光防护性能明显下降。这种临界现象可能和T-770的双重行为,即敏化和稳定化作用有关。实验表明,在本文的实验条件下,T-770易于光解,而由光解产生的自由基成了聚丙烯光氧化的重要引发根源。ESR的研究表明,T-770是通过氮氧稳定自由基>N—O~·实现其光稳定化作用的。更多还原

【Abstract】 The light protection behaviour of hindered amine light stabilizer Tinuvin-770 is studied by IB, BSR, NMR as well as observation of a mechanical property of Tinuvin-770 containing polypropylene film. The results indicate that this light stabilizer shows an optimun concentration (0.3%, W/W) in photooxidation protection of polypropylene. With the concentration of Tinuvin-770 higher or lower than the optimum, the light protection property markedly deteriorates. This phenomenon may be related to the duality of sensitizing reaction and stabilization action of Tinuvin-770. The experimental results indicate that Tinuvin-770 is easy to photolyse under the experimental conditions reported. The free radicals produced by photolysis become the origin of photooxidation initiation.Careful ESR observation shows that the light stabilization action of Tinuvin-770 is due to the formation of the stable free radical N-O.更多还原