【摘要】 研究了树外围含12个硝基偶氮苯基元新型一代碳硅烷光致变色液晶树枝状大分子G1和基元小分子M1在溶液中的最大吸收波长、摩尔消光系数、反-顺光化学异构化反应速率常数、热回复异构化反应速率常数、光化学回复异构化反应平衡常数及速率常数.G1的光致变色反应速率常数的数量级为10-1s-1,而含偶氮基元液晶聚硅氧烷的光致变色反应速率常数的数量级为10-8s-1,因此液晶树枝状大分子的光响应速率比后者快107倍.G1的光回复异构化反应平衡常数kt/kc为1.76～1.77,有作为光控开关材料的应用前景.更多还原

【Abstract】 The molar extinction coefficient, maximum absorption wavelength, reaction rate constants of trans-cis photochemical isomerization, thermal back-isomerization and photochemical back-isomerization and equilibrium constant of photochemical back-isomerization reaction of a novel photochromic liquid crys-talline dendrimer G1 of the first generation containing nitroazophenyl groups on its periphery and small mo-lecular azophenyl moiety M1 in solution were described. Photochromic rate constant of G1 in CHCl3 and THF was 10-1 s-1, but that of photochromic liquid crystalline polysiloxanes containing azophenyl moieties was 10-8 s-1, thus the photoresponsitive rate of liquid crystalline dedrimer G1 is 107 times larger than that of the latter. The equilibrium constants kt/kc of photochemical back-isomerization reaction of G1 are 1.76～1.77 approaching to 1, and thus it is appliable to photoswitch material.更多还原