​Sébastien Rolère, a CEA-Liten engineer and expert in the chemistry and physical chemistry of polymers, talked to us about the latest advances coming out of CEA-Liten labs.

How is CEA-Liten leveraging its strengths to help reduce the environmental impacts of plastics?

We have been developing bio-based and, potentially, biodegradeable, polymers for a number of years now. Our strategy has been to target applications like energy, transportation, and packaging, where these new materials could be used instead of petroleum-based plastics. Our team is particularly well-rounded, with experts in chemistry, polymer processing, recycling, and eco-design. A diverse skillset really does make a difference. We also have the resources we need at CEA-Liten to address the entire development lifecycle, starting with the chemical synthesis of new polymer matrices. Our research also covers the use of new formulations in a variety of conventional plastics and additive manufacturing processes. Our powder metallurgy, plastics processing, and assembly platform has a wide range of equipment.

What does developing these innovative materials entail?

We can fine-tune the macromolecular structures of the materials to meet the needs of our partners. This is the direct result of our research on topics like bio-based thermoplastics with controlled architectures and bio-based precursors for thermoset resin manufacturing. We also apply the principles of eco-design to our projects. This has a particular impact on our choice of raw materials, for example. To avoid competing with food crops, we only use second- and third-generation biomass. And the end of the lifecycle is just as important. We factor in recyclability issues early in the process.

What about thermoplastic composites?

We use a twin-screw** extruder to transform either polymers we synthesize in the lab or commercially-available bio-based polymers into biocomposites, which can be made up of different polymer matrices, plant fibers, and additives to improve the chemical compatibility between the different materials. We also explore new bio-based formulations for enhanced mechanical, thermal, and surface properties and greater durability. And, because our objective is to facilitate the rapid uptake of these materials by manufacturers, cost is always a factor. Our biocomposite pellet capacity is in the tens of kilos, enough for larger-scale testing on our partners' manufacturing lines. We also have industrial injection molding equipment on site to test these materials.

What's next in bio-sourced polymer R&D at CEA-Liten?

The know-how our team has acquired can now be put to work for other CEA R&D projects. For example, our new bio-based materials could be used in other CEA technologies. New energy technologies spring to mind first, but electronics and medical devices would also be good candidates. To give you an idea of what I mean, things like flexible electronic circuits, photovoltaic panels, and battery packs could all be eco-designed with bio-based recyclable materials. This could really reduce these technologies' environmental impacts. Plus, many bio-based materials are also biocompatible and bioresorbable, making them ideal for innovative medical devices.

*Second- and third-generation biomass is derived from non-food resources, such as lignocellulosic biomass (second generation) or compounds produced by micro-algae or bacteria (third generation).

**In twin-screw extrusion, materials are thoroughly mixed by two intermeshed screws as they are forced through a drum or barrel. Extrusion is a compressive manufacturing technique used to produce finished products or to transform products for further processing.