Preparation and properties of two-legged ladder polymers based on polydiacetylenes
作者:Hideyuki Tabata、Hiroaki Tokoyama、Hideo Yamakado、Tsunehisa Okuno
DOI:10.1039/c1jm13896k
日期:——
A novel diacetylene derivative, N,N′-bis[5-(3-tolylaminocarbonyloxy)-1,3-pentadiynyl]-N,N′-diphenyl-1,4-phenylenediamine (1), was prepared, where two diacetylene groups were connected by a 1,4-phenylenediamine moiety. The molecules stacked one-dimensionally and showed solid-state-polymerization reactivity above 80 °C. The decay of the monomers at 100 °C proceeded gradually without a marked induction period and was fully completed after 400 h. The obtained polymer was a crystalline solid judged by powder X-ray diffraction (PXRD) patterns and SEM imaging. The conjugated π-system of the obtained polymer was classified as a two-legged conjugated ladder. The polymer showed a broad absorption from the visible to the near IR region, indicating a decrease in the optical band gap of ca. 1.0 eV, because of the expansion of the π-conjugated system from a one-dimensional system to a ladder. The ladder polymer showed high conductivity after I2 doping from σ293K = 5 × 10−12 S cm−1 to 1.2 × 10−5 S cm−1. The conductivity depended heavily on the pressure of iodine and reached σ373K = 2.3 × 10−1 S cm−1. The activation energy of the ladder polymer was also estimated as 360 meV.
制备了一种新型二乙炔衍生物 N,N′-双[5-(3-甲苯胺基羰基氧基)-1,3-戊二炔基]-N,N′-二苯基-1,4-苯二胺(1),其中两个二乙炔基团由一个 1,4- 苯二胺分子连接。分子呈一维堆积,在 80 °C 以上显示出固态聚合反应活性。根据粉末 X 射线衍射(PXRD)图样和扫描电镜成像判断,获得的聚合物为结晶固体。所得聚合物的共轭 π 系统被归类为两脚共轭梯形结构。由于π共轭体系从一维体系扩展为梯形,该聚合物显示出从可见光到近红外区域的宽吸收,表明光带隙下降了约 1.0 eV。掺入 I2 后,梯形聚合物显示出很高的导电性,从 σ293K = 5 × 10-12 S cm-1 到 1.2 × 10-5 S cm-1。电导率在很大程度上取决于碘的压力,达到了 σ373K = 2.3 × 10-1 S cm-1。梯形聚合物的活化能估计为 360 meV。