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By employing planar thieno[3,2‐b]thiophene (TT) as end‐capped units and famous 3,4‐ethylenedioxythiophene (EDOT) or its all‐sulfur analog 3,4‐ethylenedithiathiophene (EDTT) as cores, two conjugated oligomer, TT‐EDOT‐TT and TT‐EDTT‐TT, have been synthesized and electropolymerized into electrochromic polymer films, P(TT‐EDOT‐TT) and P(TT‐EDTT‐TT), respectively. Due to strongly noncovalent inter/intramolecular interactions from SS attraction of TT‐EDTT‐TT, it has twisted molecular configuration in contrast to planar TT‐EDOT‐TT. Spectroscopic, electrochemical, morphological as well as theoretical calculation studies of these oligomers or polymers were carried out to reveal the significant influence of such molecular geometry on their physicochemical and optoelectronic properties. According to electrochromic kinetics, P(TT‐EDTT‐TT) presented preferable electrochromic behavior such as the higher optical contrast (70.8%), favorable coloration efficiency (331.3 cm2 C−1) and fast response time (0.72 s). This research will help us deeply understand the effect of spatial organization of precursor molecules on the properties of electrochromic polymers and provides a promising strategy to develop high‐performance electrochromic materials. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1041–1048 [ABSTRACT FROM AUTHOR]

ABSTRACT Solution-dispersible hyperbranched conjugated polymer nanoparticles (FT-HBCPNs) consist of an intrinsic crosslinked rigid skeleton structure of both 9,9-dihexyl-fluorene and triphenylamine repeating units, and are synthesized via the miniemulsion Suzuki polymerization, and FT-HBCPNs for highly selective and sensitive Fe3+ fluorescent detection and their application in logic gate at molecular level are successfully developed. FT-HBCPNs with an average particle size of 10.6 nm can disperse in common organic solvents. FT-HBCPNs show high selectivity and sensitivity for Fe3+ over other commonly co-existent metal ions in THF solution with a detection limit of 3.65 × 10−8 mol L−1. Furthermore, homogeneous transparent thin films of FT-HBCPNs developed by a simple spin-coating method can be reversibly quenched by Fe3+ with a detection limit of 3.09 × 10−7 mol L−1. Using Fe3+ and EDTA as chemical inputs and the fluorescence intensity signal as outputs, FT-HBCPNs films can be utilized as a logic gate at molecular level. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 3694-3700 [ABSTRACT FROM AUTHOR]

ABSTRACT Two poly(2'-aminomethyl-3,4-ethylenedioxythienylene) (PEDOT-MeNH2) derivatives were successfully synthesized by electrochemical polymerization of precursors, diethyl 3'-(((2,3-dihydrothieno[3,4- b][1,4]dioxin-2-yl) methyl)azanediyl)dipropanoate ( monomer 1) and ethyl 3-(((2,3-dihydrothieno[3,4- b][1,4]dioxin-2-yl) methyl)amino)propanoate ( monomer 2), respectively. Structure-property relationships of monomers and polymers, including electrochemical, optical properties, and morphology, were systematically explored. Significantly, the designed polymers exhibited red and orange emission signatures with high fluorescence quantum yields ( ΦF) of 0.044 and 0.045 compared with those of monomers; they may be used as building blocks for rational design of fluorescent materials. Moreover, cyclic voltammetry and spectroelectrochemistry studies demonstrated that poly(diethyl 3'-(((2,3-dihydrothieno[3,4- b][1,4]dioxin-2-yl)methyl)azanediyl) dipropanoate) ( P1) and poly(ethyl 3-(((2,3-dihydrothieno[3,4- b][1,4]dioxin-2-yl)methyl)amino) propanoate) ( P2) can be reversibly oxidized and reduced accompanied by obvious color changes from light purple to light blue for P1, and from purple to blue for P2. Furthermore, both P1 and P2 displayed higher optical contrasts (40-70%) in the visible region, favorable coloration efficiency (typically 50-230 cm2 C−1). From these results, the two polymers would be promising candidate materials for display applications. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 2081-2091 [ABSTRACT FROM AUTHOR]

ABSTRACT Oligo(oxyethylene) chains cross-linked 2,2'-bithiophene (BT-E5-BT) has been synthesized successfully. A free-standing copolymer film based on BT-E5-BT and 3,4-ethylenedioxythiophene (P(BT-E5-BT- co-EDOT)) has been synthesized by electrochemical polymerization. The electrical conductivity of P(BT-E5-BT- co-EDOT) copolymer (16 S m−1) has improved by four orders of magnitude compared to the homopolymer of BT-E5-BT (P(BT-E5-BT), 5 × 10−3 S m−1) at room temperature. Both homopolymer and copolymer films exhibit well-defined redox and satisfied coloration efficiency. Spectroelectrochemistry studies indicate that the P(BT-E5-BT- co-EDOT) has a lower band gap in the range of 1.83-1.90 eV and shows more plentiful electrochromic colours (green, blue, purple and salmon pink) compared with the homopolymer P(BT-E5-BT). The Copolymer P(BT-E5-BT- co-EDOT) shows the moderate optical contrast (26% of 480 nm) and coloration efficiency (205.41 cm−1 C−2). The copolymer method provides a novel way to fabricate a free-standing organic electrochromic device. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 1583-1592 [ABSTRACT FROM AUTHOR]

ABSTRACT 3-Dodecylthiophene end-capped two monomers: 2,8- bis-(4-dodecyl-thiophen-2-yl)-dibenzothiophene (DBT-3DTh) and 2,8- bis-(4-dodecyl-thiophen-2-yl)-dibenzofuran (DBF-3DTh) were synthesized via Stille coupling reaction. Both monomers exhibited emission peaks at about 400 nm with fluorescence quantum yields ranging from 0.16 to 0.21. The corresponding electroactive polymers poly(2,8- bis-(4-dodecyl-thiophen-2-yl)-dibenzothiophene) (PDBT-3DTh) and poly(2,8- bis-(4-dodecyl-thiophen-2-yl)-dibenzofuran) (PDBF-3DTh) were obtained by electropolymerization method and displayed good electrochemical stability. Both polymers switched between light gray in the neutral state and blue in the oxidized state. Kinetic investigations showed that PDBT-3DTh exhibited a maximum optical contrast (Δ T %) of 25.23% at 575 nm with the coloration efficiency (CE) of 196 cm2 C−1. However, the electrochromic properties of PDBF-3DTh were inferior to PDBT-3DTh. Further detailed discussions with EDOT and 3-alkylthiophenes end-capped DBT/DBF hybrid electrochromic polymers were comparatively studied. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 1468-1478 [ABSTRACT FROM AUTHOR]

ABSTRACT Two novel heterocycle-fluorene-heterocycle monomers, 2,2′-(9,9-dioctyl-9H-fluorene-2,7-diyl)dithiophene (Th-F-Th) and 5,5′-(9,9-dioctyl-9H-fluorene-2,7-diyl)bis(2,3-dihydrothieno[3,4-b][1,4]dioxine) (EDOT-F-EDOT), were synthesized via Stille coupling reaction and electropolymerized to form corresponding polymers P(Th-F-Th) and P(EDOT-F-EDOT). Furthermore, the optoelectronic properties of the obtained monomers and polymers were explored using cyclic voltammetry (CV), UV-vis, and emission spectra and in situ spectroelectrochemical techniques. The band gap values of monomers calculated by DFT were 3.75 eV for EDOT-F-EDOT and 4.03 eV for Th-F-Th, while that of P(EDOT-F-EDOT) and P(Th-F-Th) were brought down to 1.70 and 2.10 eV, respectively. Both polymers exhibited excellent redox activity and electrochromic performance. P(EDOT-F-EDOT) exhibited a maximum optical contrast of 25.8% at 500 nm in visible region with a response time of 1.2 s. In addition, the coloration efficiency of P(EDOT-F-EDOT) was calculated to be 220 cm2 C−1. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 325-334 [ABSTRACT FROM AUTHOR]