An intrinsic white-light-emitting hyperbranched polyimide: synthesis, structure–property and its application as a “turn-off” sensor for iron(iii) ions

Abstract

An intrinsic white-light-emitting single-component hyperbranched polyimide has been reported for the first time.

Fluorescent phosphine oxide-containing hyperbranched polyesters: design, synthesis and their application for Fe3+detection

“…The main reason behind this phenomenon can be explained that water might disassociate the clusters by weakening the hydrogen bonds or dipole-dipole interactions in HBP2 so as to decline the PL intensity. 38,51 When the water fraction was increased to 50%, a sudden increase in PL intensity was observed, highlighting the pronounced effects of aggregation due to the poor solubility of HBP2.…”

“…51 In addition, comparing HBP1 with HBP4, the intensity at 388 nm decreased while the intensity at over 432 nm increased after the carboxyl groups were methylated, which was probably due to the weakness of hydrogen bonds and aggregation of new clusters. 38 Effects on the optical properties of the HBPs Among the HBPs, HBP2 was selected to study the effects on the optical properties of excitation wavelength, polymer concentration, and solvents. Before the designed experiments, the absolute quantum yield (QY = 11.41%) and fluorescence lifetime (FL = 2.27 ns) of pure HBP2 were measured, as shown in Fig.…”

“…33,34 A strong fluorescence phenomenon, namely clusteroluminescence (CL), has been widely observed upon the purposeful introduction of electron-rich heteroatoms (i.e., O, N, P, S, and halogens) or their corresponding unsaturated groups (i.e., PQO, CQO and CQC) into the chemical structures of hyperbranched polymers. 35,36 In recent years, chromophorefree hyperbranched polymers have been increasingly designed and developed, such as hyperbranched polycarbonates, 37 hyperbranched polyimides, 38 hyperbranched polyethers, 39 and hyperbranched phosphates. 40 In addition, hyperbranched polyesters (HBPs) are one of the most fascinating types of polymers due to their good biocompatibility and degradability.…”

Hyperbranched poly(ester ether)s as an amplified fluorescence sensor for selective and sensitive Fe3+ detection and bioimaging

“…On the other hand, the branched structure increases the possibility of encounter between excitons and analytes or quenchers. 14 Abundant fluorescent hyperbranched polymers have been developed in recent years, including conjugated hyperbranched polymers, 15,16 fluorescent dye-modified hyperbranched polymers, 12,17 AIEgen-derived hyperbranched polymers, 18,19 and chromophore-free hyperbranched polymers.…”

“…In particular, chromophore-free hyperbranched polymers have aroused increasing attention due to the advantages of environmental friendliness, facile preparation, and good biocompatibility. Hyperbranched polymers with unconventional chromophores have expanded from hyperbranched poly(amide amine)s 20 to hyperbranched polycarbonate, 11 hyperbranched polyimide, 14 hyperbranched polycarbonate, 21 poly(amino ester), 22,23 hyperbranched polyesters, 24 hyperbranched polyether, 25 hyperbranched polyethylenimine, 26 and hyperbranched polysiloxanes. 27,28 Several mechanisms have been proposed to explain their luminescence, such as the oxidation or acidification of tertiary amine units and the aggregation of carbonyl groups or other oxygen-rich heteroatoms.…”