Preparation and Fluorescent and Magnetic Properties of Polyurethane/Eu(MA)₃ Films

Abstract

Europium(III) (Eu3+)‐doped polyurethane films were prepared by mixing Eu‐methacrylic acid complex (Eu(MA)3) with aliphatic polyurethane oligomer and subsequently curing under UV irradiation. Transmission electron microscopy photos and the appearance of the resulting hybrid films showed that phase separation occurred only at an Eu(MA)3 content above 20 wt.‐%. Fluorescence spectra indicated that the fluorescence of Eu3+ was barely influenced by the polyurethane matrix and its intensity increased with an Eu(MA)3 content in the range of approximately 0 to 10 wt.‐%. An obvious applied external‐field‐dependent magnetization (M) of polyurethane/Eu(MA)3 films, namely, an increasing M at low field and a decreasing M at high field, was observed at room temperature from the hysteresis loops, which was influenced by both the Eu(MA)3 content and the ultrasonication imposed on the coatings before curing. It seems that ultrasonication leads to a thermodynamically‐unstable structure of Eu3+ in hybrid films, which can be fixed by UV curing but gradually rearranges to its original form during the thermal‐curing process, and enhances the diamagnetic part of the hybrid film. Thus, the magnetic property of Eu3+‐doped polyurethane film at room temperature can be adjusted by simply changing the preparation method and the Eu(MA)3 content instead of the type of Eu3+‐organic complex.magnified image

Structural properties of the multiwall carbon nanotubes/poly(methyl methacrylate) nanocomposites: Effect of the multiwall carbon nanotubes covalent functionalization

“…The absorption bands originating from PMMA are the dominant absorption bands in the FT‐IR spectra. The absorption bands at 2,996, 2,953, and ∼2,884 cm −1 are assigned to stretch mode of a CH bond vibration (CH 2 , CH 3 ) . The most characteristic change is associated with two absorption bands at 1,730 and 1,690 cm −1 which were partially overlapped.…”

New copoly(urethane‐methacrylate)s obtained by adjusting the content of the poly(1,2‐propanediol ortho‐phthalate): Transparent, thermal, and mechanical properties

“…Polyurethanes (PU) can vary from rubbery materials to glassy thermoplastics and from linear polymers to thermosetting plastics 1. PU can be used in extensive applications, including optics,2–5 automotive parts,6 optoelectronics,7–12 and biocompatible materials13 for its outstanding properties, such as transparence in a wide wavelength range, strong damage resistance for laser irradiation, chemical stability, good dimensional stability, etc.…”

Photoluminescent Epoxy/Gd2O3:Eu3+ UV‐cured Nanocomposites

“…It is one of the best host materials for sensitizing the Eu 3+ combined with its high photo‐ and chemical stabilities 18, 19, 23, 25–27. On the other hand, transparent polymeric matrices provide good mechanical support and patternability for the inorganic fillers 28–32. Herein, we report the preparation of photocurable epoxy‐based materials containing cubic Gd 2 O 3 :Eu 3+ nanorods.…”