New photoactive composite based on ethyl vinyl acetate (EVA) and SrAl2O4:Eu,Dy or Sr4Al14O25:Eu,Dy were prepared by melt mixing or extrusion methodologies. The phosphorescent behavior and material properties of the polymer-phosphor composites were studied. The morphology of the polymer and the composites were studied by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy (EDS). The SEM. shows that the physical and chemical behavior of the matrix and the extrusion conditions were primarily responsible for the surface morphology. TEM and EDS show that the phosphor particles were uniformly dispersed in the EVA matrix. A broad band of ultraviolet (UV)-excited phosphorescence of SrAl2O4:Eu,Dy and Sr4Al14O25:Eu,Dy phosphors and the respective composites were observed at wavelengths of 516 nm and 490 nm, respectively. The photoluminescence (PL) spectra showed less intense phosphorescence but no shift in the wavelength of the emission peak for all the composites. The Hamburg wheel test was done on all the composites and the PL measurements before and after the test showed almost no change in the intensity of the emission. Thermal studies showed that the presence of the phosphors in the matrix slightly increased the crystallinity of EVA, which leads to higher melting enthalpies. Tensile testing shows very little change in the tensile strength and flexibility of the ethylene vinyl acetate copolymer. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 115: 579-587, 2010