Preparation of lanthanide (Eu³⁺, Tb³⁺)-complex-grafted copolymer of methyl methacrylate and maleic anhydride films and the promising application as LED luminous layers

In this work, we report the preparation of lanthanide (Eu³⁺, Tb³⁺)-complex-grafted copolymer of methyl methacrylate and maleic anhydride films. The lanthanide complex with three amino groups was used to react with poly(methyl methacrylate-co-maleic anhydride) (P(MMA-MAH)) via the amidation method. Fourier transform infrared (FT-IR), Transmission electron microscope (TEM), Scanning electron microscope (SEM), Thermogravimetric analysis (TGA) were employed to characterize those polymers. Luminescent properties were evaluated through conducting Photoluminescence (PL) excitation spectra, emission spectra and fluorescence decay curves measurements. The infrared analysis reveals the amidation between amino groups and anhydride rings. The comparatively uniform morphology can be observed in the images of TEM and SEM. These polymers can emit intense characteristic lights including red light from Eu³⁺ ions and green light from Tb³⁺ ions under 294 nm excitation. The lifetimes of polymers are short (about 1 ms). Meanwhile, these luminescent polymers exhibit high thermal stability (T₅ > 200 °C). We also stimulate a lamp to illustrate the possible application. All these approved interesting results suggest that they hold significant promising applications as luminous layers for optoelectronic devices.