The biopolymer polyhydroxybutyrate (PHB) is a promising base material for new, environmentally friendly plastics due to its resource-saving production from renewable raw materials and its good biodegradability even under adverse environmental conditions. However, for the successful industrial use of PHB, a significant increase in elongation and impact strength at the same time is required. In this work, PHB is modified in an industry-oriented process by means of reactive extrusion in a twin-screw extruder. Copolymerization with a suitable soft phase not only improves the mechanical properties, but in particular increases the thermal resistance of the material. Based on these initial successes, the interaction of the components used is to be investigated in detail in the future and the formulation needs to be further improved in order to obtain a bioplastic that can be used commercially.