fig1
Figure 1. Schematic illustration of the formation, crosslinked structure, and multifunctional properties of PHHE. PHHE: PEG/HDI/HAPP/EG; APP: ammonium polyphosphate; PEG: polyethylene glycol; HDI: hexamethylene diisocyanate; EG: expanded graphite; PHH: PEG/HDI/HAPP; HAPP: hydroxylated ammonium polyphosphate.







