When asked about the advantages to using a bioplastic over a conventional plastic, the first thing Garilli pointed to was the environmental benefit calculated by using Ingeo PLA.
"Looking at the plastics used, this prototype refrigerator had a carbon footprint that was 83 percent smaller than when using petroleum-based plastics. Per fridge, this was 22 percent smaller," he said.
However, there were also benefits relating to the properties, chemical and mechanical, of the bioplastic itself.
"When it came to producing the refrigerator liners, which are big thermoformed products, the issue of distortion arises," he said. "There were basically two choices: We could produce the liners by thermoforming extruded amorphous PLA sheet, or we could opt for a PMMA/PLA multilayer liner. As the latter was a known solution, it made sense to use it and to go for a 100 percent PLA solution later, if it worked."
The first surprise was how well it worked.
"During thermoforming, the material is stretched, which results in tension. When using HIPS, a sheet with a thickness of minimally 3.5 millimeters is required to avoid distortion issues. ... We were excited to find that with PLA, this was far more uniform, making it possible to reduce the layer thickness to 1.2 millimeters, which not only meant that less material was used, but also that the weight of the liner was reduced," Frank Diodato, NatureWorks business director, said.
For now, Electrolux has put the project on hold until the time is right for a product launch. According to Garilli, the market will develop, but "when and how this develops depends on various factors, including the interest from the market."