Mechanical properties of linear low-density polyethylene fire-retarded with melamine polyphosphate

The ecologically friendly flame retardant melamine polyphosphate (MPP) was prepared and incorporated into linear low-density polyethylene (LLDPE). The impacts of this halogen-free flame retardant on the mechanical characteristics of LLDPE were investigated in this research. The flame-retardant properties were evaluated, and the mechanical properties, including flexural, tensile, compressive, fracture toughness, and shear behaviors, were tested. The weight fraction of the filler material ranges from 5% to 30%. The influence of filler weight content of the produced composites was evaluated by means of a universal testing machine in order to identify their behavior. The flammability of composites was highly improved with the addition of MPP. It was observed that the Young's modulus and flexural modulus increased almost linearly; similarly, the tensile fracture strength and tensile yield strength increased with the increase in MPP weight fraction. The tensile elongation at break decreased sharply between zero and 10% weight fraction, followed by a slight decrease up to 30% weight fraction. The flexural strength peaked with the increase in MPP weight fraction. The compressive strength and shear strength of the specimens were directly proportional to MPP content up to 15% and 30%, respectively. The novelty in the optimization of MPP content as well as the preparation method reveal a wide range of applications. (c) 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 134, 46770