Unorthodox luminogenic polymers without aromatic luminogens have attracted great interest in recent years; however, the low fluorescence efficiency is still a big drawback. In this paper, we synthesized a fluorescent hyperbranched polysiloxane with both carbonyl and vinyl groups (P1). Surprisingly, it exhibited nontraditional intrinsic luminescence with the highest quantum yield up to 43.9% among the reported silica-containing hyperbranched fluorescent polymers to date. Reference oligomers P2 and P3, theoretical calculations, and transmission electron microscopy were employed to explore the fluorescence mechanism. The high fluorescence quantum yield is ascribed to the synergism of vinyl and carbonyl groups as well as the Si−O grouppromoted through-space conjugation. Thus, the supramolecular hyperbranched polysiloxane was assembled by conjugation to increase the oscillator strength and decrease the band gap. Moreover, the solvent effect and pH dependency properties of P1 and its application as an Fe 3+ probe were also studied.

Hyperbranched polysiloxane (HBPSi) is attracting increasing attention due to its intrinsic fluorescence and good biocompatibility. However, it is very challenging to explore its biological applications because of the low fluorescence intensity and quantum yield. Herein, we introduced rigid β-cyclodextrin to the end of flexible polysiloxane chain to synthesize a novel fluorescent polymer (HBPSi-CD) and explore its biological applications. Results showed that the fluorescence intensity and quantum yield of HBPSi-CD, compared with HBPSi, were significantly enhanced. Theoretical calculations and transmission electron microscopy demonstrated that the synergy effect of intra/intermolecular hydrogen bonds and hydrophobic effect promoted the formation of large supramolecular self-assemblies and space electron delocalization systems, leading to intense fluorescence. Notably, the biocompatible HBPSi-CD not only lighted up mouse fibroblast cells, but also possessed high ibuprofen loading capacity (160 mg g–1) and superior pH-responsive drug release performance. This work promoted the development of biological applications of HBPSi.

The presented work shows an impressive multicolour luminescence hyperbranched polysiloxane attributed to the multiring through-space conjugation named “multiring induced multicolor emission” (MIE), as well as its application in data encryption.

Non-conjugated fluorescent polymers have attracted great attention due to their excellent biocompatibility and environmental friendliness. However, it remains a huge challenge to obtain a polymer with high fluorescence quantum yield (QY) and multicolor emission simultaneously. Herein, we reported three kinds of nonaromatic hyperbranched polyborates (P1-P3) with multicolor emission, surprisingly, P2 also exhibits an unanticipated high QY (54.1 %). The natural bond orbital (NBO) analysis and density functional theory (DFT) calculation results revealed that the synergistic effect of rigid BO 3 planar and flexible carbon chain, as well as the through-space dative bond in supramolecular aggregate, were the key factors contributing to the ultrahigh QY of P2. Moreover, the applications of P2 in Fe 3 + ions detection and cell imaging were also investigated. This work provides a new perspective for designing non-conjugated fluorescent polymers with both high QY and multicolor emission.