Preparation and properties of modified ammonium polyphosphate synergistic with tris(2-hydroxyethyl) isocynurate for flame-retardant LDPE

Abstract UF-SiAPP was prepared by modifying ammonium polyphosphate with the urea formaldehyde resin (UF), tetraethylorthosilicate (TEOS), and vinyltriethoxysilane (A-151). Moreover, a new intumescent flame retardant (IFR) used for low density polyethylene (LDPE) obtained mixing tris(2-hydroxyethyl) isocynurate (THEIC). The structure, morphology, mechanical properties of retardants LDPE composites were characterized Fourier transform infrared spectroscopy, scanning electron microscopy, TG, universal material testing machines. Furthermore, flame-retardant comprehensively investigated limiting oxygen index (LOI), UL-94, cone calorimetry tests. results show that exhibits excellent hydrophobic good compatibility after being modified UF, TEOS, A-151. And are significantly improved adding IFR-containing UF-SiAPP. Especially, attained LOI value 30.5% reached V-0 level introducing 20.0 wt% 10.0 THEIC. tensile strength 13.55 MPa, which 10.33% higher than LDPE/IFR UF-APP 13.21% without THEIC in same proportion. smoke tests demonstrate addition not only effectively improves residual carbon content thermal stability but also reduces emissions.