Recently, the Institute for Plastics Technology (IKT) at the University of Stuttgart, in collaboration with the Chair of Polymer Materials at the University of Bayreuth, is conducting research focusing on the foaming properties of modified PLA–PHA blends. The core objective of this research project is to develop bio-based particulate foam materials, which may ultimately replace traditional petroleum-based materials (such as expanded polystyrene PS).
The microstructure of expanded polylactic acid (PLA, left image) and the PLA blend containing 20% PHBV (right image) shows that, without additional modification, the PHBV component significantly affects the density and pore structure of the foam material.
The research focuses on improving the processing performance of PLA-the low melt strength of PLA has been a major technical bottleneck in its foaming process. By blending with PHA, researchers aim to specifically optimize the mechanical properties and processing characteristics of the material.
Furthermore, the team plans to reactively extrude the mixture with surfactants to prepare a special material with low density and a fine-pore structure, suitable for the application requirements of granular foam.
The PLA and PHA blend design aims to integrate the core advantages of the two materials: PHA is biodegradable, while PLA has advantages in cost and supply stability.
Notably, the two blend components have different melt temperature ranges, a characteristic believed to have a positive effect on the foaming process.
Since both process and material parameters have a key impact on the foaming effect, the research team will use a material model to reveal the relationships between these complex factors. This model will be continuously optimized and improved using machine learning techniques. This collaborative project integrates the expertise of the Institute for Plastics Technology (IKT) at the University of Stuttgart in biopolymer processing with the core capabilities of the University of Bayreuth team in foam material processing and digital technology.
The long-term goal of this research is to achieve the large-scale supply of sustainable granular foam materials, providing an environmentally friendly alternative to existing traditional plastic foams.
