Novatein thermoplastic protein, produced from bloodmeal, embrittles after production due to plasticiser loss, causing poor energy absorbing properties (impact strength = 0.5 kJ/m2). The addition of a low Tg second phase in Novatein means energy absorption during fracture can be improved. Several avenues were used to explore impact modification; namely addition of nano-scale core-shell particles, reactive blending of Novatein and functionalised PE, and bio-based ternary blends of Novatein, PBAT and epoxy functionalised chain extender. It was found that the greatest increase in energy absorption occurred in blends containing core-shell particles (impact strength at 30 wt. % particles = 3 kJ/m2). This was attributed to good particle dispersion, efficient stress transfer to the elastomeric particle and decrease in interparticle distance, allowing the matrix to elongate freely during fracture. In contrast, in-situ formation of morphologies conducive to impact modification through reactive extrusion of Novatein and modified PE proved difficult due to viscosity ratio and interfacial tension that weren’t favourable in producing stable, dispersed morphologies. However, blends containing zinc ionomer performed well in mechanical testing, with high elongation and greatly increased impact strength (impact strength at 20 wt. % PE = 2.3 kJ/m2). This was attributed to strong ionic interactions between the zinc carboxylate salt and charged amino acids in the protein phase. Similar morphologies were displayed in Novatein/PBAT ternary compatibilized blends. The introduction of epoxy functionalities caused a fine dispersion of PBAT and a maintenance of tensile properties along with a threefold increase in notched impact energy (1.5 kJ/m2) was observed. In conclusion, the study shows that it is possible to significantly increase energy absorption of protein based thermoplastics through reactive blending of synthetic or biobased polymers, or incorporation of pre-synthesised particles.