PREPARATION AND PROPERTIES STUDIES OF HALOGEN-FREE FLAME RETARDANT STYRENE–BUTADIENE RUBBER BASED ON APP AND PUMAPP

Abstract

ABSTRACT Microencapsulated ammonium polyphosphate with polyurethane resin (PUMAPP) was prepared by in situ polymerization and was characterized by X-ray photoelectron spectroscopy. The particle's water solubility was decreased through the microencapsulation of ammonium polyphosphate (APP) with the polyurethane resin. The flame retardation of APP/pentaerythritol (PER) and PUMAPP/PER flame retarded styrene–butadiene rubber (SBR) composites was studied using limiting oxygen index and UL-94 tests, and the thermal stability was evaluated by thermogravimetric analysis and microscale combustion colorimeter. Results demonstrated that the flame retardancy of the SBR/PUMAPP/PER composites was better than that of the SBR/APP/PER composites at the same additive loading. The water-resistant properties of the SBR composites containing PUMAPP and APP were also studied. Scanning electron microscopy and Fourier transform infrared spectrometry were used to analyze the morphological structure and the component of the residue chars formed from the SBR composites accordingly, and the mechanical properties of the materials were also studied.