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Nonconventional luminophores without large conjugated structures are attracting increasing attention for their unique aggregation-induced emission(AIE) properties and promising applications in optoelectronic and biomedical areas. The emission mechanism, however, remains elusive, which makes rational molecular design difficult. Recently, we proposed the clustering-triggered emission(CTE) mechanism to illustrate the emission. The clustering of electron-rich nonconventional chromophores with π and/or n electrons and consequent electron cloud overlap is crucial to the luminescence. Herein, based on the CTE mechanism, nonaromatic polymers containing multitype heteroatoms(i.e., O, N, and S) and involving amide(CONH) and sulfide(-S-) groups were designed and synthesized through facile thiol-ene click chemistry. The resulting polymers demonstrated typical concentration-enhanced emission, AIE phenomenon, and excitation-dependent emission. Notably, compared with polysulfides, these polymers exhibited much higher solid-state emission efficiencies, because of the incorporation of amide units, which contributed to the formation of emissive clusters with highly rigidified conformations through effective hydrogen bonding. Furthermore, distinct persistent cryogenic phosphorescence or even room temperature phosphorescence(RTP) was noticed. These photophysical behaviors can well be rationalized in terms of the CTE mechanism, indicating the feasibility of rational molecular design and luminescence regulation.

Artemisia vulgaris hydrogel (AVH) was acetylated (AAVH) and characterized by FTIR, CP/MAS 13C-NMR spectroscopic techniques and thermogravimetric analysis. Flynn–Waal–Ozawa model was used to investi...

Pure organic luminogens with fluorescence–room temperature phosphorescence (RTP) dual emission have significant fundamental importance and promising applications. So far, most dual emissive materia...

Nonconventional luminogens without remarkable conjugation have attracted significant attention due to their scientific and technical importance. Their emission mechanism, however, is still under debate. Recently, we proposed the clustering-triggered emission (CTE) mechanism, namely the clustering of nonconventional chromophores and subsequent electron cloud overlap (delocalization) together with simultaneous conformation rigidification, to rationalize the emission. To further check it, nonaromatic polyurethanes (PUs) bearing carbamate (NHCOO) groups were designed and synthesized. While being virtually nonemissive in dilute PU/DMF solutions, PUs are found to be highly emissive when concentrated or aggregated as powders and films. Furthermore, room-temperature phosphorescence (RTP) is detected from the solid powders and films. Clustering of NHCOO groups and electronic communications among carbonyl (CO) units, N and O atoms are accountable for the emission. Such stereoelectronic interactions were also corroborated by the liquid IR (LIR) measurement. In addition, the aggregates of PUs are also useful for explosive detection and cell imaging.

Physical blending with hydrophilic nanoparticles (NPs) is generally adopted to improve the performance of hydrophobic membranes. Stable immobilization of the NPs remains challenging due to the weak bonding. Covalent bonding is expected to overcome this problem. Herein, γ-methacryloxy propyl trimethoxy silane (MPTS) was grafted onto PVDF membranes, affording a versatile materials platform to firmly anchor hydroxyl-rich nanomaterials (HRNs) (TiO2, SiO2, β-FeOOH-1, β-FeOOH-2, etc.) via a facile dehydration process. The stability of the resulting hybrid PVDF-g-PMPTS/HRN membranes is remarkably improved, as evidenced by their almost unchanged water contact angles even under ultrasonication for 30 min. The immobilization yield of HRNs, hydrophilicity, roughness and water flux of the membranes are enhanced with increasing graft degree of PMPTS. The resulting hybrid membranes exhibit much better water flux recovery ratio and BSA rejection ratio compared to the pristine PVDF membrane, owing to their excellent anchoring stability and outstanding hydrophilicity. This work provides a general effective chemical route to the construction of hybrid hydrophilic membranes with high performance.

Nonaromatic photoluminescent polymers have attracted great attention due to their intriguing photophysical properties and promising implications in optoelectronic and biological areas. The luminescence from these nonconventional luminophores can be well rationalized by the clustering-triggered emission mechanism. Sulfur, although as an n-electron-rich element with big radius, is not been widely utilized in construction of nonconventional luminophores despite of its potential competitiveness in nonaromatic photoluminescent polymers. Herein, the "click" type Michael polyaddition is utilized to construct sulfur-bearing nonconventional luminophores, and two sulfur enriched nonaromatic poly(thioether sulfone)s (PES) are obtained, which demonstrate fluorescence-phosphorescence dual emission. More investigations concerning the monomer of bis(vinylsulfonyl)methane are further proceeded to support acquired results. Finally, the application of explosive detection by the prepared PES is also conducted.