Synthesis of polymer fluorescent probe by ring opening polymerization of ε ‒ caprolactone induced by 1 ‒ pyrene methanol and its recognition of Zn2+

With the development of industry, the treatment of industrial waste water containing metal ions has become a difficult problem in environmental governance. Polymer fluorescent probe is an effective method for identifying and enriching metal ions in waste water. The ring ‒ opening polymerization of ε ‒ caprolactone was initiated with 1 ‒ pyrene methanol as the initiator and the fluorescent group, and then it was chemically linked with the recognition group dimethylpyridine amine by 2‒chloroacetyl chloride to obtain the polymer fluorescent probe L. The chemical structure of polymer fluorescence probe L was confirmed by 1 H NMR. The recognition performance of polymer fluorescence probe L for metal ions was studied by fluorescence spectra. The results show that the polymer fluorescence probe L has specific recognition ability for metal ion Zn 2+ . By optimizing the optical properties, the selectivity and anti-interference ability of fluorescence probe L to Zn 2+ were improved. The linear recognition range of Zn 2+ is from 2 × 10 –6 mol ∙ L -1 to 9 × 10 –6 mol ∙ L -1 , and the detection limit is 6.38× 10 –7 mol ∙ L -1 . According to the plot curve of job, the complex ratio of Zn 2+ and probe L is 1 : 1. The fluorescence principle of coordination between dimethylpyridine amine (DPA) and zinc ion (Zn 2+ ) mainly involves the inhibition of photo induced electron transfer (PET) mechanism. In summary, probe L can be used to detect Zn 2+ in acetonitrile rapidly, so it has a certain application value in the identification and separation of metal ions in industrial waste water.