| In this study, a number of flame retardant additives were compounded with recycled PET in order to determine their effectiveness in preparation of a flame retardant PET molding compound. In doing so, four different primary flame retardant additives were used; namely brominated polystyrene, brominated polycarbonate, red phosphorus, and magnesium hydroxide. Antimony trioxide was used as a primary flame retardant synergist. The additives were melt blended with the PET at various concentrations alone or in combination, The flammability and mechanical properties of the formulations were studied. All of the additives, except the magnesium hydroxide, were shown to significantly increase the flame retardancy of the final product. The brominated polycarbonate at a 16%, with antimony trioxide as a synergist, yielded the only UL 94 V-0 rating; however, all of the formulations containing the brominated polystyrene and the red phosphorus performed well in the horizontal ASTM D 635 rate of burn test. |
