Elke Metzsch-Zilligen, Fraunhofer LBF, presented initial results of the pinfa – Fraunhofer LBF testing of recyclability of PIN flame retarded polymers, by multiple extrusion and ageing. Tests with polypropyleneand PIN FR piperazine pyrophosphate showed recyclability and conservation of fire performance and some mechanical properties for extrusion at 200°C.
There was some loss of mechanical performance (elongation at break), significant loss of antioxidants, and loss of fire performance with extrusion at higher temperature (230°C). For polyamides (PA6 with melamine cyanurate PIN FR and glass fibre reinforced PA66 with aluminium diethylphosphinate PIN FR), fire retardancy was also conserved during recycling. There was again some loss of elongation at break, but this loss was lower than with the same recycling of the neat polymer (without PIN FR). Other tests are underway on cables (PE/EVA, LLDPE) and films (PP).