Microencapsulated Red Phosphorus In The Polymer And Its Flame Retardant Mechanism Study

The main body of this thesis is about the HDPE (5200 B) and PA6 (1013 B)and their blending composites to be flame retarded by microcapsulerization red phosphorus mother granule (MRP), firstly using burned oxygen index and ignited oxygen index to characterize their combustion properties respectively. MRP is beneficial to the flame retardant of the HDPE and PA6 composites, but make composites the impact strength decline. Adding a few PA6 can improve the effect of the flame retardant of the HDPE/MRP compound material, and is beneficial to mechanical properties of the HDPE/MRP compound material. Fix PA6:MRP all quantity at 15% o'clock , it is at HDPE: PA6: MRP = 85:4:11 o'clock that the limit oxygen index gained maximum, 22.1%. In the HDPE/PA6 composites, the PA6 putting in, make the material rigidity enhanced, but have the material tenacity weakened. Under the situation of fixing MRP contents, follow PA6 contents increasing by, HDPE/PA6 (contents enhance)/ MRP composites flame retardant is strengthened; the material rigidity enhanced, but the material tenacity weakened. In MRP:PA6:HDPE =11:39:50, MRP/PA6/HDPE composites impact strength are minimal.Dynamics studies put an indicating that, MRP may improve the HDPE and PA6 composites stability and the carbonated rates, but make composites the mechanism of oxidation degradation change. The oxidation degradation of HDPE is mainly R2 mechanism, HDPE/MRP composites the diffusing mechanism (D), transits gradually to F2 and F3 mechanism ; But PA6 oxide degradation approaches F1 mechanism, increasing by with MRP amounts, the composites complicated degradation process happen, final stage gives second order reaction (F2 mechanism), carbonates on (second order reaction or multi-level reaction) the bounding surfaces. A few HPDE or PA6 putted in may improve the carbonated rate of the PA6 or HDPE /MRP composites respectively, at the PA6/ MRP / HDPE composites mainly with PA6 the oxidation degradation mechanism is similar to that of PA6/MRP, giving R2 mechanism; while in the HDPE/MRP/PA6 composites with HDPE mainly the oxidation degradation process is more complicated, analogy with HDPE/MRP, giving F2 mechanism mainly.