Shuwei Cai,Shuzhong Wang,Dongxu Wei,Haijun Niu,Wen Wang,Xuduo Bai
Four kinds of novel polyamides (PAs) containing pyrrole core with different triarylamine (TAA) groups were designed and synthesized. These PAs exhibit good solubility in various organic solvents and excellent thermal stability. The two PAs prepared from cyclohexane-1,4-dicarboxylic acid exhibit fluorescence maximum at 475–476 nm with quantum yields up to 39.0% and 57.3% in N , N -dimethylacetamide (DMAc) solution. Furthermore, the polymer films show reversible electrochemical redoxidation with color changing from yellowish to khaki to dark blue. Especially, the films have high coloration efficiency (up to 143 cm 2 C −1 at 750 nm) and after over 1000 s the films still exhibit continuous cyclic stability of electrochromism . What's more, these PAs could be used as the photoelectric conversion material owing to their excellent optoelectronic properties.
To better understand the structure–property relationships and the mechanisms of the electronic switching behavior of functional polyimides, a new series of diamines containing a pyrrole core with different side groups were designed and synthesized. Three novel, thermally stable and aromatic polyimides (Py6FPIs) containing the as-designed diamines were prepared. They were fabricated into memory devices sandwiched between an Al top electrode and an indium-tin oxide (ITO) bottom electrode by spin-coating. The polyimides exhibited high thermal stability with glass transition temperatures (Tg) around 300 °C as determined by DMA. The memory devices were found to show nonvolatile bistable write-once-read-many (WORM) memory characteristics with diverse switching threshold voltages and ON/OFF ratios, depending on the electron affinity of the pendent groups. The low-conductivity state and the high-conductivity state could be sustained under a constant bias or a refreshing voltage pulse of 1.0 V. The switching mechanism and the memory effects were finely demonstrated with the aid of molecular simulations and electronic absorption spectra of these Py6FPIs.
危险品化学品经营许可证（带存储）