Side-Chain Effect on the Nature of Thermochromism of Polysilanes
Side-Chain Effect on the Nature of Thermochromism of Polysilanes
复制标题
侧链对聚硅烷热致变色性质的影响
DOI：
10.1021/ma00080a049
复制
发表时间：
1994
期刊：
影响因子：
--
通讯作者：
R. West
中科院分区：
文献类型：
--
作者：
C. Yuan;R. West
聚硅烷聚合物1在300-400 nm的紫外线区域显示出强烈的电子吸收带，该吸收带归属于a-*电子跃迁2，涉及电子沿硅主链的广泛离域。电子吸收的能量与聚合物链的构象密切相关，类似于众所周知的 x-共轭聚合物（例如聚二乙炔和聚噻吩）中的 xx* 转变。 4 随着温度降低，许多二烷基聚硅烷 5 的吸收带会逐渐或突然转变为更长的波长，这与无序转变有关。迄今为止，人们付出了相当大的努力来揭示突然热致变色转变的性质，特别是在对称二烷基聚硅烷中。聚合物 (n-烷基2Si)„，其中 n-烷基
Polysilane polymers1 display an intense electronic absorption band in the ultraviolet region 300-400 nm, which is assignedto a-* electronic transition2 involving extensive delocalization of electrons along the silicon backbone. The energy of the electronic absorption is strongly correlated with the conformation of the polymer chain, similarly to the xx* transition in well-known x-conjugated polymers such as polydiacetylene3 and polythiophene. 4 Many dialkylpolysilanes5 undergo either a gradual or abrupt shift of the absorption band to longer wavelength as temperature is lowered, associated with a disorder-order transformation. To date, considerable efforts have been devotedto disclosing the nature of abrupt thermochromic transition, especially in the symmetric dialkylpolysilanes. Polymers (n-alkyl2Si)„, where n-alkyl