Synthesis and Characterization of Novel Non-conjugated hyperbranched polysiloxanes with AIE Effect

To obtain unconjugated hyperbranched polysiloxane (HBPSi), the triethoxyvinylsilane (A-151) and simple polyol compounds were used as raw materials, and two kinds of unconjugated HBPSi which the terminal group is -OH group and C=C bond were synthesized via a simply transesterification condensation, and the factors that affecting their luminescence are also further discussed. The results showed that, both of these two HBPSi exhibits excellent aggregate induced emission effect. The structure rich in π electrons or lone pair electrons in the raw materials basically maintains its original state in the polymer, and the spatial conjugation of the two leads to the luminescence of non-conjugated polymers. A large number of -OH groups in the polymer can form hydrogen bonds, and the promotion of hydrogen bonds makes the target products further gather spontaneously, which further enhances the spatial conjugation and improves the rigidity of the molecules. It can be concluded that under certain conditions, the larger steric hindrance of the molecule itself will affect the polymerization degree of the final product and the aggregation degree of the polymer molecule, while low polymerization and aggregation degree will result in higher energy required for the material to fluoresce. This study provides some reference significance for the preparation of non-conjugated luminescent materials with higher fluorescence intensity.