Poly(4-trimethylsilyl diphenyl acetylene) (PTMSDPA) has strong fluorescence emission, but its application is limited by the effect of aggregation-caused quenching (ACQ). Copolymerization is a commonly used method to adjust the properties of polymers. Through the copolymerization of 4-trimethylsilyl diphenyl acetylene and 1-trimethylsilyl-1-propyne (TMSP), we successfully realized the conversion of PTMSDPA from ACQ to aggregation-induced emission (AIE) and aggregation-induced emission enhancement (AEE). By controlling the monomer feeding ratio and with the increase of the content of TMSDPA inserted into the copolymer, the emission peak was red-shifted, and a series of copolymers of poly(TMSDPA-co-TMSP) that emit blue–purple to orange–red light was obtained, and the feasibility of the application in explosive detection was verified. With picric acid (PA) as a model explosive, a super-quenching process has been observed, and the quenching constant (KSV) calculated from the Stern–Volmer equation is 24,000 M−1, which means that the polymer is potentially used for explosive detection.
As a low energy consumption, simple operation and environmentally friendly separation method, membrane separation has attracted extensive attention. Therefore, researchers have designed and synthesized various types of separation membrane, such as metal organic framework (MOF), covalent organic framework (COF), polymer of intrinsic micro-porosity (PIM) and mixed matrix membranes. Some substituted polyacetylenes have distorted structures and formed micropores due to the existence of rigid main chains and substituted side groups, which can be applied to the field of membrane separation. This article mainly introduces the development and application of substituted polyacetylenes in gas separation and liquid separation based on membrane technology.
Room-temperature organic magnetic materials have been a sought-after but challenging topic for a long time. Besides the reported organic-containing magnets including pure organic radicals, charge-transfer salts, and coordination polymers, we report a novel and alternative approach to fabricate purely organic/polymeric magnets based on the crystal of a 4-substituted 1,6-diyne (M1) and its polymer (P1). Both of the white M1 crystal and the black P1 powder samples exhibit room-temperature magnetism. The saturation magnetization of P1 is about 0.25 emu g−1 and its Curie temperature is higher than 400 K. After repeated recrystal of M1 and precipitation of P1 to thoroughly remove the metal-catalyst residues, the room-temperature magnetism of M1 and P1 is tentatively assigned to the stable radicals in the solid samples. The results demonstrated in this work suggest an unprecedented strategy to obtain room-temperature organic magnets.
Multi-axis atropisomers are ubiquitous in nature, and their intricate stereoconformations not only deepen stereochemical understanding but also elucidate fundamental principles of molecular atropisomeric dynamics. Nevertheless, insights into multi-axis atropisomerism remain limited. This work presents a systematic investigation of three classes of LaPlente-type biaxial atropisomers based on naphthalene rotors and phenyl linkers. Thermodynamically and kinetically controlled interconversion of molecular conformations is achieved in 22-NB, 11-NB, and 11-NB-8DMe. Concurrently, a direct correlation between molecular dynamics and electronic through-space conjugation (TSC) is elucidated. Furthermore, absolute separation of syn and anti conformers is accomplished in 11-NB-2DMe, whose distinct TSC-induced fluorescence enables direct visualization of dynamic conformer populations and kinetics during temporally sequential crystallization. This work provides fundamental mechanistic insights into multi-axis atropisomer stereochemistry and establishes a fluorescence-based approach as an in-situ platform for real-time analysis of molecular dynamics across life and materials sciences.