1,5,7-Triazabicyclo[4.4.0]dec-5-ene (TBD) with pKa of 26.03 in acetonitrile can be effectively released by photolysis of TBD.HBPh4 salt, which represents a new family of short-wave UV photobase generators. This photobase generator enables the photoinduced living ring-opening polymerization of cyclic esters and the photoinduced cross-linking of various polymeric materials containing the hydroxyl-ester groups.

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(1 of 9)Planar integrated systems of micro-supercapacitors (MSCs) and sensors are of profound importance for 3C electronics, but usually appear poor in compatibility due to the complex connections of device units with multiple mono-functional materials. Herein, 2D hierarchical ordered dual-mesoporous polypyrrole/graphene (DM-PG) nanosheets are developed as bi-functional active materials for a novel prototype planar integrated system of MSC and NH 3 sensor. Owing to effective coupling of conductive graphene and highsensitive pseudocapacitive polypyrrole, well-defined dual-mesopores of ≈7 and ≈18 nm, hierarchical mesoporous network, and large surface area of 112 m 2 g −1 , the resultant DM-PG nanosheets exhibit extraordinary sensing response to NH 3 as low as 200 ppb, exceptional selectivity toward NH 3 that is much higher than other volatile organic compounds, and outstanding capacitance of 376 F g −1 at 1 mV s −1 for supercapacitors, simultaneously surpassing single-mesoporous and non-mesoporous counterparts. Importantly, the bi-functional DM-PG-based MSC-sensor integrated system represents rapid and stable response exposed to 10-40 ppm of NH 3 after only charging for 100 s, remarkable sensitivity of NH 3 detection that is close to DM-PG-based MSC-free sensor, impressive flexibility with ≈82% of initial response value even at 180°, and enhanced overall compatibility, thereby holding great promise for ultrathin, miniaturized, body-attachable, and portable detection of NH 3 .

Starting from α-tetralone and maleic anhydride, novel AB-type amino anhydrides 3 and 5 were synthesized in good yields and obtained in high purity without self-condensation. The tetrahydro[5]helicene monomer 3 could be readily polymerized in m-cresol to give polyimide 8 with high molecular weight. Although direct polymerization of the [5]helicene monomer 5 afforded only an insoluble oligomer, the high molecular weight [5]helicene-based polyimide 9 could be readily obtained as powders and thin films from the precursor polyimide 8 upon treatment with bromine at elevated temperatures. Young's moduli of thin films as assessed by TMA for polyimides 8 and 9 were 2.91 and 6.34 GPa at 25 °C, respectively. Random and regularly alternating copolymers of the AB monomer 5, m-phenylenediamine, and 4,4‘-(hexafluoroisopropylidene)diphthalic anhydride were made and showed improved solubility over the homopolymer 9.

A new, practical approach to a variety of highly electrooptically active polymers for device development is described. It involves the use of a new thermally cross-linkable, hyperbranched oligomer containing nonlinear optical (NLO) chromophores as a macromolecular dopant in a common host polymer. A series of NLO polymeric blends were readily formulated and showed large and stable electrooptic (EO) coefficients (up to 65 pm/V). In comparison with previously studied linear NLO polyimides and guest-host polymers doped with molecular chromophores and even linear NLO analogous oligomers, this new approach offers clear advantages for device development in terms of improved poling efficiency, larger EO coefficients, good temporal stability, and versatile material formulation.

While a number of highly luminescent copper­(I) halide based hybrid materials built on coordinate bonds (Cu–L; L = N, P, S-based ligands) have been obtained, the poor structural stability largely limited their commercialization. In contrast, according to the previous studies, the ionic structures (L-free) are more stable than those built on Cu–L coordinate bonds. However, the extremely weak emission hinders their optical applications. Herein, we report a tetra-alkylammonium-cation-induced strategy for the synthesis of stable and highly luminescent ionic CuBr-based hybrid materials. It is interesting to find that the tetra-alkylammonium cations with different chains could induce diverse CuBr-based anions. Moreover, most of these CuBr-based hybrids are highly luminescent, which makes them promising candidates as an alternative to phosphors and with potential applications in sensing.

A series of perylene-containing polyimides and copolyimides have been synthesized and characterized by DSC, TGA, NMR, UV-vis, and X-ray powder diffraction measurements. Xerographic electrical measurements indicated that perfectly alternating copolyimides had higher photosensitivities than those of homopolyimides and random copolyimide. After annealing, polyimide films showed a redshift in UV-vis absorption and improved photosensitivity due to an increase in crystallinity, as indicated by wide-angle X-ray diffraction measurements.

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