The effects of the addiction of amine functional reactive elastomer on Poly (lactic acid) (PLA) were investigated. The blends were produced varying the elastomer concentrations (8%, 14% and 20%) using chloroform as solvent, via solvent-cast 3D printing (SC-3DP) as films. Chemical interactions, morphology, thermal and mechanical properties of the PLA/elastomer blends were evaluated by Fourier transform infrared spectroscopy (FTIR), scanning electronic microscopy (SEM), differential scanning calorimetry (DSC), termogravimetry (TGA), dynamic mechanical analysis (DMA) and tensile strength test. IR spectra of the blends showed interactions between PLA carboxyl groups and elastomer amine groups that lead to the formation of amide groups. The increase of the vibration bands intensity of the carbonyl and hydroxyl groups suggests that hydrolysis effect was strong throughout the reaction. Thus, the water formed as a reaction subproduct acted like an expansion agent creating a porous morphology on the blends, as observed in the SEM images. According to the thermal properties analyses, the blends showed less thermal stability and higher degree of crystallinity than the neat PLA. The 8% PLA/Elastomer blend showed the higher crystallinity value, 4.2 times greater than that for neat PLA. However, the crystallinity of the blends reduced as the elastomer content was increased. The increase of elastomer content shifted the glass transition (Tg) of the PLA rich phase to lower temperatures while the Tg of the elastomer rich phase tended to be at higher temperatures. The cold crystallization temperature of PLA changed also to lower temperatures that could be due to the nucleation effect of the elastomer. Mechanical properties analysis showed no significant changes, except for the elongation that reduced by 50% compared to the neat PLA film, which could be explained by the foam structure formed during the 3D printing.