A series of new polyamides (PAs) were designed and synthesized based on two novel triarylamines (TAA) with fused ring groups via phenyl bridge through the Suzuki coupling reaction. These novel PAs have amorphous structure and excellent thermal stability, with a carbon residue rate of up to 70% at 800 degrees C in nitrogen atmosphere. In the process of electrochemical oxidation, there is no obvious recessionary in current and transmittance over 1000s with a cycle time of 10s, which showing high contrast and excellent cycle stability. And the electrofluorochromic (EFC) performance can also be adjusted by being applied voltage. 1NAT-CA and 9AAT-CA have solvatochromic effect in absorption, fluorescence (PL) in solvents, 1NAT-6F and 1NAT-BA have aggregation-induced emission enhancement (AIEE) properties in solid state. The kind of multifunctional integrated PAs show characteristics of responding to voltage, explosive and hazardous gas stimuli and the stimuli-responsive mechanisms are investigated, which have the prospect of application in photoelectric sensors, explosive detectors and high-contrast displays.

Six novel donor–acceptor conjugated polymers were designed and synthesized by the Stille coupling reaction of triarylamine derivatives as donor units with isoindigo derivative or benzothiadiazole as acceptor units. These polymers have good solubility and film-forming properties in common organic solvents. The char yields of polymers in nitrogen atmosphere at 800 °C range from 34 to 60%. In particular, these conjugated polymers exhibit high photoluminescence (PL) quantum efficiency (up to 42.9%). These polymers demonstrate two pairs of redox peaks with low onset voltages (0.51 V vs. Ag/AgCl for P5) and narrow band gaps (Eg = 2.52 ~ 2.95 eV). The colors of all polymer films change significantly with the applied voltage increasing. Moreover, the polymers show high coloring efficiency (up to 163%) and maintain good electrochromic (EC) cycle stability over 500 s. In addition, excellent results in terms of memory storage (ON/OFF = 1.2 × 104), 2,4,6-Trinitrophenol (TNP) detection (Ksv = 45,790 M-1) can meet the requirements of multifunctional materials.

The display devices of the future will tend to be multifunctional, and the dual-mode device for emission and coloration satisfies the requirements of practical applications. We synthesized materials with electrochromic (EC) and electrofluorochromic (EFC) properties through the combination of triarylamine (TAA) and ladder-like polysilsesquioxanes (LPSQs). The ladder-like structure was confirmed by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and Si-29-NMR techniques. These polymers exhibit up to 37.3% fluorescence (PL) quantum efficiency (Phi(PL)) and show strong solid-state fluorescence because TAA groups are effectively isolated in ladder-like backbone in LPSQs. The TAA-LPSQs films exhibit reversible change from colorless of bleached state to blue or green of oxidized state. Among them, the optical contrast of the MPA-LPSQ film synthesized from 1-(4-(bis(4-methoxyphenyl)amino)phenyl)-3-(3-(triethoxysilyl)propyl)urea is as high as 83.0% at 787 nm, which shows excellent cycle stability over 1000 s. Unique structure and good electrochemical activity of TAA-LPSQs make them promising materials for dual-mode device. The EC/EFC device (ECD/EFCD) was assembled using MPA-LPSQ as an active layer which showed good performance. In addition, TAA-LPSQs exhibit excellent sensitivity to 2,4,6-trinitrotoluene (TNT) and 2,4,6-trinitrophenol (TNP) detection, so these materials can also be applied as highly sensitive chemosensor for explosives.

Four novel multifunctional electrochromic materials (PTT, PDTT, PNT and PDNT) based on tetraphenylethylene (TPE) and triphenylamine (TPA) units by Stille coupling reaction were prepared. Electrochemical impedance spectroscopy (EIS) measurements found that four polymers had low resistance values which improved their electrochemical and electrochromic properties. In addition, the maximum coloration efficiency (CE; eta) value is 126 cm(2)/C at 1246 nm of PDTT, bleaching and coloring response times are 2.6 s and 1.6 s, respectively. There is no significant change of performance after a 100 cycle scanning. In addition to their excellent electrochromic properties, they also exhibit a strong aggregation-induced emission (ME) effect. Furthermore, the fluorescence color of PDNT changed from bright green to black when voltage was applied from 0.0 to 1.6 V. Four polymers responded rapidly to light and they maintained stability over a 1000 s cycle.

Four novel materials containing isoindigo derivatives were synthesized via Stille coupling reaction. These polymers not only have excellent electrochromic properties (the highest electrochromic efficiency reaches 195 cm(2)C(-1)), but also have low charge transfer resistance (R-ct). The range of switching threshold is from -1.7 V to -4.0 V and the current ratio of the device beyond 10(-5) for memory device. Moreover, the polymers can also be used as explosive detector. A sharp drop in the fluorescence intensity of the polymer appeared when trinitrotoluene (TNT) or 2, 4, 6-trinitrophenol (TNP) was added.

Four kinds of main-chain benzoxazine polymers (PBZ) containing triarylamine (TAA) units were synthesized by Mannich reaction and characterized by 1H nuclear magnetic resonance (NMR), Fourier transform infrared (FT-IR) techniques, etc. Thermal, optical, photophysical and electrochemical properties were studied. The 50% of char residue is left in N2 at 800 °C. The polymers are soluble in common organic solvents and easily spin-coated onto indium‑tin oxide (ITO) coated glass substrates. All the polymers have voltage window ranging from 0 to 1.8 V, and the colors change from yellowish to dark red when voltage is applied. Meanwhile, device assembled from polymer exhibit significant color changes. Furthermore, the polymers also have promising potential application in explosive detection and resistance memory devices.

Methyl methacrylate was used as a main monomer in this paper. Firstly poly(methyl methacrylate) (PMMA) was synthesized by bulk polymerization of methyl methacrylate(MMA) in mold. Subsequently MMA was copolymerized with acrylonitrile (AN) and styrene (St) respectively in mold. The as-prepared products were tested by tensile and impact test. The results of test show that with the increase of the AN content in the copolymer, the tensile strength of the copolymer showed a downward trend for the internal defects after rising first for the forming of intermolecular hydrogen bond. The impact strength of the copolymer showed a rising trend for the formation of hydrogen bonds. Meanwhile, with the increase of the St content, the tensile strength of the copolymer showed a rising trend for the introduce of strong rigidity benzene. The impact strength of the copolymer increased first for the rigidity of benzene pendant group and then decreased for the decline accumulation degree of molecular chain.