Flame-retardency properties of tris(2-hydroxyethyl) isocyanurate based charring agents on polypropylene

Tris(2-hydroxyethyl) isocyanurate based charring agent (TBCA) was synthesized by melt polycondensation with tris(2-hydroxyethyl) isocyanurate (THEW) and terephthalic acid as raw materials. It was characterized by Fourier transform infrared spectroscopy, elemental analysis, H-1-NMR, and thermogravimetric analysis (TGA). TBCA was blended with ammonium polyphosphate (APP) to form an intumescent flame retardant (IFR) for polypropylene (PP). The charring properties of TBCA was tested by flame retardancy in the PP/APP/TBCA (PP/IFR2) composite and compared with that of the PP/APP/THEIC (PP/IFR1) composite. The results show that PP/IFR2 had lower flame-retardant properties but better water resistance than that of the PP/IFR1 composite because PP/IFR2 could still obtain a V-0 rating after it had been soaked in water at 70 degrees C for 96 h, whereas PP/IFR1 could not achieve any rating after 36 h. Their combustion performance was further evaluated by a cone calorimeter test, their thermal degradation processes were studied by TGA, and the morphology of the char residue was observed by scanning electron microscopy. (C) 2015 Wiley Periodicals, Inc.