The Study On Synthesis And Flame Retardancy In HDPE/PC Blends Of Phosphaspiro Hydroxybenzene Ester

The good property of polyolefine material can been gotten through blenging polyolefine and engineering plastic. polycarbonate(PC) been used as firstly choice engineering plastic because of resisted impact and dimension stability. The high density polyethylene is not well used in some fields because of lower mechanical strength. HDPE/PC alloy has been regarded as one of important blending material. And up to now, there is not a kind of flame retardant can been added to HDPE/PC. phosphospiro hydroxybenzene ester has better stability than existing phosphorus containing of flame retardant. And because of higher phosphorus and carban containing, they can been added to HDPE/PC as a kind of intumescent flame retardant.Two flame retardant about Spirophosphate phenol ester(BN-SPD) and Spirophosphate cresol ester (DBN-SPD) were synthesized and characterized by FTIR and ~1H-NMR in this thesis. Some factors that effecting the reaction which is dropping temperature and time, the ratio of reaction system were investigated. Two flame retardant are very importantal phosphorus-containing flame retardants, they exhibiting higher decomposable temperature-According to TGA data known their decomposable temperature were about 280℃. they can been added to general plastic as flame retardant.HDPE/PC alloy materials have been gotten through blending polycarbonate(PC) and compatibilizer and polyethylene(HDPE) according to different proportion. The mechanical property of the blendings were investigated by means of draw and impact test machine. The result indicated that the mechanical capability is best when compatibilizer is MAHLLDPE(CMG9904) and ratio of compatibilizer and PCand HDPE is 8:25:75. Tensile strength is 28.3MPa, Izod impact strength is 15.48kJ/m~2. Compared with pure HDPE, the mechanical properties increased 26.1% for tensile strength and 23.7% for Izod impact strength, respectively.But HDPE/PC alloy easy burning because of lower limiting oxygen index(LOI)value, only 18.9. The two flame retardant of Phosphaspiro hydroxybenzene ester were added to HDPE/PC alloy according to different proportion. The limiting oxygen index(LOI) up to about 24.5 when the proportion of flame retardant is 30%. Spirophosphate cresol ester (DBN-SPD) and melamine phosphate(MP)together were used as intunescent flame retardant adding to HDPE/PC, The LOI is higher when the ratio of Spirophosphate cresol ester (DBN-SPD) and melamine phosphate(MP) is 2:1, it reached 27.2. The results showed that it had high thermal stability and good ability of char formation itself, this coflame retardant is a very effective flame rerardant in HDPE/PC. It also found that mechanical property less effect on material. The tensile strength decreased 8.98%. Izod impact strength decreased 12%. But LOI increased 12%.