A novel flame-retardant acrylonitrile-butadiene-styrene system based on aluminum isobutylphosphinate and red phosphorus: Flame retardance, thermal degradation and pyrolysis behavior

Aluminum isobutylphosphinate (APBu) and its synergistic system with red phosphorus (APBu/RP) were used to flame-retard ABS. With the addition of APBu to ABS, the flame retardance of the material was greatly improved, that LOI value was as high as 29.8%, and a UL-94 V-0 rating was obtained; moreover, heat release parameters obtained from cone calorimetry decreased. However, the smoke release of the material during combustion increased. When RP was added to ABS-APBu system, flame-retardant synergism was gained, and it was helpful to reduce the smoke release of the material. The decomposition behaviors of materials were studied by thermogravimetric analysis (TG), and it was found that the residues of materials at 700 °C increased with the addition of APBu or APBu/RP. The flame-retardant mechanisms of APBu and APBu/RP were analyzed by Fourier transform infrared spectrum (FTIR), scanning electron microscopy (SEM) and pyrolysis-gas chromatograph/mass spectrometer (Py-GC/MS). Results suggested that the addition of RP to ABS-APBu further enhanced the flame retardation of APBu both in the gaseous phase and condensed phase, leading to a high synergistic effect.