Progressive flame⁃retardant actions of quaternary composite system in rigid polyurethane foams

doi:10.19491/j.issn.1001-9278.2022.08.005

Abstract

Abstract:

A quaternary flame?retardant system was constructed using dimethyl methyl phosphonate （DMMP）， 10?（2，5?two hydroxytoluene）?10?hydrogen?9?oxygen hetero?10?phosphoryl phenylene?10?oxide （DOPO?HQ）， expandable graphi?te （EG）， and aluminum hydroxide （ATH） as raw material， and its flame retardant behavior in rigid polyurethane foam （RPUF） was investigated using thermogravimetric analyzer， cone calorimeter， and limiting oxygen index analyzer. The results indicated that the quaternary flame retardant system exhibited a synergistic flame?retardant effect in a wide temperature range during combustion. DOPO?HQ could generate an additional flame?retardant effect with EG/DMMP/ATH ternary flame?retardant system for the RPUF composites， resulting in an increase in limiting oxygen index by 30.8%. Meanwhile， the peak heat release rate， the RPUF composites with the quaternary flame?retardant system showed a lower total heat release rate and a lower total smoke release rate than the RPUF composites with the EG/DMMP/ATH ternary flame?retardant system. Moreover， the char residue rate were further improved， indicating that a synergistic effect resulting from the quaternary flame retardant system based on DOPO?HQ and EG/DMMP/ATH. In addition， the residual char was characterized by scanning electron microscope. The quaternary flame retardant system could act as a barrier in the condensed phase to exert the progressive flame?retardant actions in the early， middle， and later stages of combustion.

Key words: polyurethane foam, flame retardancy, quenching effect, synergistic carbonization

CLC Number:

TQ314.24⁺8

YANG Zhi, XI Wang, QIAN Lijun, HU Lishuang. Progressive flame⁃retardant actions of quaternary composite system in rigid polyurethane foams[J]. China Plastics, 2022, 36(8): 28-35.

Figures/Tables 15

References 31

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样品	450L	催化剂	PAPI	DMMP	DOPO⁃HQ	EG	ATH
RPUF	72	14.76	108	-	-	-	-
8D/6E/12A	72	14.76	108	15.58	-	11.69	23.37
8D/2DH/6E/12A	72	14.76	108	15.58	3.90	11.69	23.37
8D/4DH/6E/12A	72	14.76	108	15.58	7.80	11.69	23.37
2DH	72	14.76	108	-	3.90	-	-
4DH	72	14.76	108	-	7.80	-	-

样品	450L	催化剂	PAPI	DMMP	DOPO⁃HQ	EG	ATH
RPUF	72	14.76	108	-	-	-	-
8D/6E/12A	72	14.76	108	15.58	-	11.69	23.37
8D/2DH/6E/12A	72	14.76	108	15.58	3.90	11.69	23.37
8D/4DH/6E/12A	72	14.76	108	15.58	7.80	11.69	23.37
2DH	72	14.76	108	-	3.90	-	-
4DH	72	14.76	108	-	7.80	-	-

样品	T_{5 %}/℃	T_{50 %}/℃	700 ℃残炭率/%
RPUF	271	352	19.0
8D/6E/12A	195	363	25.7
8D/2DH/6E/12A	188	357	25.1
8D/4DH/6E/12A	203	361	27.9
2DH	267	353	18.6
4DH	270	351	19.5

样品	T_{5 %}/℃	T_{50 %}/℃	700 ℃残炭率/%
RPUF	271	352	19.0
8D/6E/12A	195	363	25.7
8D/2DH/6E/12A	188	357	25.1
8D/4DH/6E/12A	203	361	27.9
2DH	267	353	18.6
4DH	270	351	19.5

样品	LOI/%
RPUF	18.6
8D/6E/12A	29.7
8D/2DH/6E/12A	30.3
8D/4DH/6E/12A	30.8
2DH	18.9
4DH	19.3