Blends of low-density polyethylene (LDPE) with Polystarch N were prepared by extrusion. Tensile properties, thermal behavior, and natural weathering of these blends were investigated as a function of blend composition. The addition of Polystarch N to the matrix decreased the tensile properties and the degree of crystallinity of LDPE when the proportion of Polystarch N increased in the blend, as revealed by differential scanning calorimetric studies. Scanning electron microscope analysis of the blends retrieved after being exposed to natural weathering showed that natural degradation increased with increase in the amount of Polystarch N in the LDPE and is ascribed to higher extent of chain scission as revealed by Fourier transform infrared spectroscopy analysis. (C) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013