Samples of PC/PMMA blend having proportion 6/4, 4/6 and 2/8 were doped with acetyl-acetonate of Eu(acac)$_3$ having concentrations of 0-16%. Through Photoacoustic Spectroscopy (PAS) the interaction of Eu$^{3+}$ with the blends was studied using the visible range 200-530 nm, monitoring a wide absorption band from 280 to 320 nm, where results pointed that 2/8 blend presents the highest absorption. Preliminary luminescent emission showed higher emission for lower Eu(acac)$_3$ amounts and suggests that the 2/8 blend as more efficient at 615 nm. In addition, it is presented a study of thermal diffusivity and heat capacity evolution related to the doping amount for all blend proportions. Normalized thermal diffusivity is higher for 2/8 blend ($α_{\rm mean} ∼ 5.64 \times 10^{-3}$ cm$^2$s$^{-1}$) and the specific heat was almost constant (c$_{\rm p(mean)}∼ 1.66$ Jg$^{-1}$K$^{-1}$).