Correlation between compounding parameters and the degradation of poly(lactic acid)/starch composites during the compounding process [Dataset]

Poly(lactic acid) (PLA) is one of the most important bioplastics with good mechanical properties and reduced environmental impact compared to petro-based plastics. In order to improve both sustainability and cost-efficiency, PLA can be filled with low-cost particles, such as native potato starch. However, during processing in a twin-screw extruder, PLA and starch are prone to thermal, hydrolytic, and mechanical degradation, which can deteriorate composite properties. This dataset systematically describes how key compounding parameters including screw speed and configuration, temperature profile and PLA pre-drying time influence the properties of PLA-starch composites containing 50 wt.% native potato starch. Various analytical methods were used to characterize the properties (Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA), Melt Volume Rate (MVR), Scanning Electron Microscopy (SEM), color measurements). The results show that thermal properties remain largely unaffected by the chosen compounding parameters. In contrast, significant changes are observed in thermal stability, viscosity, color, and morphological structure with changes in process parameters. Higher screw speeds and temperatures increase thermomechanical stress, leading to a higher MVR value, indicating lower molecular weight. Color measurements reveal significant discoloration due to starch degradation and PLA chain scission, which correlate with increasing yellow and red tones and a decrease in brightness at higher thermomechanical stress due to elevated screw speed and temperatures. Overall, the data emphasizes the complex interactions between process parameters, in particular screw speed and temperature profile as well as the physicochemical properties of PLA-starch composites, providing valuable insights for the design of the compounding process in order to prevent pre-damage to the composites.
IMPORTANT: In case you use the data please cite our corresponding article.