Synthesis And Optoelectronic Properties Of Polyarylsulfones Containing Triarylamine-carbazole

Electrochromic(EC) can be defined an a reversible and visible change in the transmittance and/or reflectance of a material by means of a voltage or an electric current, and the materials with these properties are called Electrochromic Materials. For now, electrochromic materials are composed of two major categories: inorganic electrochromic materials and organic electrochromic materials. Inorganic electrochromic materials are the first to be studied, which mainly refer to transition metal oxides, such as WO3, V2O5, NiO, etc, with many advantages: high color contrast, good stability, strong adhesion, etc. Contrasted with inorganic electrochromic materials, organic electrochromic materials have good thermal stability, long performance life in devices, short switching time, good memory effect, less energy consumption, many colors, high transmittance in different status, etc. And that make them to be a popular topic in this field. In recent years, electrochromic devices are used in many areas, such as smart window, electrochromic display, glare-free mirror, no-consumption information storage, etc.Thermal stability is one of the key factors of the electrochromic devices’ performance life. So, it’s a good way that combining electrochromic material with high performance engineering polymer, which have good thermostability, chemical stability and mechanical properties, to get a sort of ideal electrochromic material. Polyarylsulfone is one of high performance engineering polymer as already mentioned. In our former work, our research group has succeeded on introducing triphenylamine and carbazole into the system of polyarylsulfone. But we didn’t do further study on the electrochromic properties.In this work, we compounded a series of polyarylsulfone which contained decorated triphenylamine structure by the way of two-step C-N coupling. We tried to find the relationship between the structures and the photoelectrical properties, and studied the electrochromic properties of these materials.First, we polymerized aniline with different para-substituents and DFDPS to get a series of polyarylsulfone which contained para-substituted triphenylamine in the main chains. These polymers have good molecular weight and thermal stabilities. We found the UV-absorption maximum wavelengths of the polymers, which have electron-donating substituents on para-position, are higher than the polymer with no para-substituents. And the maximum emission wavelength become lower with the decreasing of the electron-donating ability of substituents. These polymers also have good fluorescence quantum yield, which means they have the potential to be used as luminescent materials. Combined with the cyclic voltammetry test, we found that these polymers have oxidation and reduction potential, and good HOMO energy level.Second, we polymerized a series of polyarylsulfone which contained triphenylamine or carbazole in the side chains and triphenylamine in the main chains. These polymers have good molecular weight and thermal stabilities. By the UV-vis test and cyclic voltammetry test, we found that these polymers have good HOMO energy level. Then we studied the electrochromic properties of the polymers with triphenylamine in the side chains. We found that polymers have good electrochromic properties and electrochemical stability. These sort of polymers with good thermal stabilities and electrochromic properties have the potential to be used in electrochromic devices.