偶氮苯取代吡唑啉衍生物PMMA薄膜的光诱导双折射性质研究

芳香族偶氮化合物的顺反异构化反应长期以来一直受到人们的关注 1,2 ] .当把偶氮生色团引入到聚合物中时 ,在线性偏振光的激发下 ,偶氮生色团能发生“反 -顺 -反”光异构化循环 ,并且偶氮发色团会沿着偏振光偏振方向的法线重新取向 ,从而导致光致双折射现象的发生 3 ] .因此 ,这类聚合物在光学存储 4 ] 、光学开关和全息光栅 5] 等方面具有重要的应用价值 .为研究偶氮苯的结构对光诱导双折射性质的影响 ,本文制备了偶氮苯取代的三苯基吡唑啉衍生物 ,并把其掺杂入 PMMA中 ,研究了薄膜的偏振光诱导光致双折射性质 ,讨论了温度对其光致双…

Preparation of Azophenyl-substituted Pyrazoline Derivatives and Studies on Photoinduced Birefringence of Doped PMMA Films

Three azo-dyes, 4′-{(2-hydroxylethyl)methyl]amino}-4-nitroazobenzene(1), 1-4-(4′-nitrophenyl)-azophenyl]-3,5-biphenyl-2-pyrazoline(2) and 1-4-(4′-nitrophenyl)-azophenyl]-5-(4′-hydroxylphenyl)-3-phenyl-2-pyrazoline(3) were synthesized. The polarized photoinduced birefringence and relaxation process of those azo-dyes doped with PMMA films were investigated under polarized laser intensity. The results indicate that compounds with pyrazoline group have a high storage rate and thermal stability. It has been found that the birefringence signals decrease with the increase of the temperature, but the effect of temperature is different for the three compounds. Compounds 2 and 3, with pyrazoline groups have a good thermal stability at room temperature, and compound 3 can even keep 30% of its maximum birefringence at 90 ℃.