초록 |
Expandable graphite (EG) is a flame retardant material that is useful for polyurethane foam (PUF) synthesis, but it shows the disadvantage of reducing mechanical strength, which limits application field. In this study, to overcome the limitations of EG / PUF composites, cellulose-based flame retardants as a reinforcement were prepared using novel method. The grinded microcrystalline cellulose was coated with mussel-derived adhesive protein, dopamine, and formed an iron phosphonate coordination network on the surface. Grinded microcrystalline cellulose based flame retardant (GCF) was incoporated to the EG / PUF composites and the total content of EG and GCF was adjusted to 15%. The NEAT PUF had a low LOI value of 19.3%, while the PUF mixed with 3 wt% of GCF and 12 wt% of EG (GCF3) had a high LOI value of 25.1%. Especially, the compressive strength of GCF3 was remarkably enhanced (21 wt %) than the PUF containing 15 wt % of EG (EG15). |