EU project develops PIN FR compounds using waste incineration ash and nitrogen FRs for PP, PA (polypropylene, polyamide).
The Horizon 2020 (EIT Raw Materials) project, WAPOL, is developing flame retarded polymers for the automotive industries using PIN FRs from waste materials.
PP filled with 20-30% municipal waste incineration ash (treated bottom ash) achieved UL94HB @ 1.6 mm with mechanical properties similar to those of PP-T20.
Polyamide 6 with 10 – 30% FRs (both unfilled and 25% glass fibre grades) achieved UL94-V0 @ 0.8 mm. For example, WAPOL PA6-GF25-V0 shows density of 1.38 g/cm3, GWFI 960/2 and GWIT 875/2. Preliminary results on mechanical properties of PA6-GF25-V0 show tensile strength at break around 120 MPa, tensile modulus 9000-9500 MPa, Izod impact strength (ASTM, notched) around 70 J/m. Further optimisation is ongoing.
Results to date, presented at the IAFSS Symposium 2021, show that the WAPOL compounds can, in most cases, achieve specified fire performance at lower cost and lower greenhouse emissions than reference brominated/antimony FR compounds. Further work is underway to assess the impact of WAPOL material loadings on polymer mechanical and electrical characteristics.
“”Environmental and cost studies of flame retardants derived from ashes for use in polymers”, F. Amon, S. Dahlbom, P. Blomqvist, RISE, poster at IAFSS Symposium https://uwaterloo.ca/international-symposium-on-fire-safety-science/
“WAPOL: Waste materials for Antimony substitution in flame retarded POLymers”, project website https://projects.dii.unipd.it/wapol/project/