Roland Klein, Fraunhofer LBF, presented the EU-funded (FP7) PHOENIX project www.phoenix-eu-project.eu aimed at upscaling production of phosphorylated lignin polymer as a bio-based PIN flame retardant. Dialysis testing proved that the process effectively reacted phosphorus covalently into the lignin polymer.
However, the use of PCl3 posed issues of handling and residual halogen (failure to achieve halogen-free standards) incompatible with upscaling to industry, so a process instead using P2O5 was successfully developed. The phosphorylated lignin showed to be an effective polymeric PIN FR in ABS, and further work is underway to improve compatibility with polypropylene by reacting hydrophobic groups into the P-lignin polymer (using propionic acid).