Abstract: Super tough poly (lactic acid) (PLA)-based blends showing non break impact behavior have been developed. The blend contains a PLA resin, (b) a thermoplastic elastomeric block copolymer, and (c) a functionalized polyolefin copolymer. The blend is used as matrix to incorporate one or more additives, such as fillers (e.g., natural fibers and/or mineral fillers), nucleating agents, and/or chain extenders to form composites. In some embodiments, the blend is the continuous phase and the one or more additives are the dispersed phase. The composites exhibit improved impact strength and heat distortion temperature compared to neat or virgin PLA. For example, in some embodiments, the impact strength of the composite is from about 60 J/m to about 140 J/m and/or the HDT of the composite ranges from about 60 to about 115° C.