Polycarbonate Flame Retarded by Non-Halogen Solid Aromatic Phosphate

Non-halogen solid aromatic phosphate(SDP) is a flame retardant with good heat resistance.It was synthesized recently in our laboratory.SDP was employed to flame retard polycarbonate(PC),and its effects on flame retardancy(including limited oxygen index(LOI) and UL94 flame retardant grades),mechanical properties(including tensile strength,tensile modulus,flexual strength,flexual modulus and elongation at break),thermal decomposition behavior of PC and char after burning were investigated.It shows from the experiments that after modified with SDP,the flame retardancy of PC increases significantly.With 6% of SDP introduced,PC reaches UL94 V-0 rating(1.6mm) and the LOI reaches nearly 35%.In addition,SDP improves tensile strength,tensile modulus,flexual strength, flexual modulus and elongation at break with a loading less than 4%.Thermogravimetry-infrared(TG-IR) data show that SDP accelerates crosslinking and char forming of PC and makes it happen ahead of schedule,but can not improve char yeild.