Performances of Blends Between Poly(pentabromobenzyl acrylate) and Magnesium Hydroxide as Flame Retardants for Polypropylene Block Copolymers

Combinations between poly(pentabromobenzyl acrylate), and highly pure and surface treated magnesium hydroxide offer improved flame retardant systems for polypropylene block copolymers enabling to reduce significantly the need for high loadings of antimony trioxide used as synergist. According to a series of bench-scale tests, these flame retardant blends are contributing to good melt flow properties, significant increase of thermal dimensional stability and ease to recycle scraps online or at the end of life of plastic parts. Drastic smoke reduction is benefit provided by the presence of magnesium hydroxide. The high molecular weight of poly(pentabromobenzyl acrylate) makes it unlikely to leach out or migrate from plastic parts or to penetrate through the cell membranes of living tissue. The use of ethylene/1-octene copolymers is recommended if high impact properties are required.