Sunlight-activated long persistent luminescent polyurethane incorporated with amino-functionalized SrAl2O4:Eu2+,Dy3+ phosphor

An amino-terminated long persistent luminescent phosphor (Amino-SrAl2O4:Eu2+,Dy3+) was prepared based on inorganic SrAl2O4:Eu2+,Dy3+ phosphor, chemically modified with 3-aminopropyltriethoxysilane (KH550). Fourier transform infrared and X-ray photoelectron spectral, thermogravimetric and scanning electron microscopic measurements confirmed the successful synthesis of Amino-SrAl2O4:Eu2+,Dy3+. Then this amino-functionalized phosphor was introduced into polyurethane (PU) through urea linkages, and the effects of the chemical combination of Amino-SrAl2O4:Eu2+,Dy3+ and PU on the morphology, structure, storage stability, and mechanical, thermal and luminescent properties of the resultant long persistent luminescent polyurethane (LPLPU) were investigated. Compared with SrAl2O4:Eu2+,Dy3+/PU composites prepared by physical blending, the LPLPU shows better mechanical properties and storage stability due to the good compatibility of Amino-SrAl2O4:Eu2+,Dy3+ with PU. More residues and higher initial decomposition temperature are observed because the interaction of the amino-phosphor and PU delays the degradation. Study of the luminescent effect reveals that the LPLPU shows more than 10h afterglow after cessation of the excitation light, and the brightness of green light in darkness is basically the same as that of LPLPU and SrAl2O4:Eu2+,Dy3+/PU. (c) 2016 Society of Chemical Industry