Synthesis and application of furan⁃based phosphoramidite flame retardants for flame⁃retardancy of PA6

doi:10.19491/j.issn.1001-9278.2024.11.018

Abstract

Abstract:

To inhibit the exothermic situation of polyamide 6 （PA6） during combustion， furan groups that can char at high temperature were introduced into flame retardants. A series of flame retardants containing furan groups were designed and synthesized， and their flame⁃retardant and heat⁃inhibition properties as well as corresponding mechanisms were investigated by means of limiting oxygen index， vertical combustion experiment， and cone calorimetry. The results indicated that the furan groups could generate different heat suppression effects under different external environments and internal morphologies. The PA6 compounds containing large⁃molecule flame retardants exhibited a better heat suppression effect than those with small⁃molecule flame retardants according to the cone calorimetric test results.

Key words: furan group, charring, polyamide 6, flame retardancy

CLC Number:

TQ314.24

XU Zhun, JIA Meng, SHAN Hao, XU Bo. Synthesis and application of furan⁃based phosphoramidite flame retardants for flame⁃retardancy of PA6[J]. China Plastics, 2024, 38(11): 104-113.

Figures/Tables 19

References 14

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样品	T_{5 %}/℃	T_max1/℃）	R_max1 /%·min^-1	T_max2 /℃	R_max2 /%·min^-1	T_max3/℃	R_max3/%·min^-1	残炭量/%
BPDFA	200	259	7.7	405	6.9	—	—	39.1
POCFA	190	250	11.6	—	—	—	—	40.0
DPCFA	180	220	5.3	255	9.2	580	2.8	39.5
DFAPO	180	323	3.0	529	1.9	—	—	48.1

样品	T_{5 %}/℃	T_max1/℃）	R_max1 /%·min^-1	T_max2 /℃	R_max2 /%·min^-1	T_max3/℃	R_max3/%·min^-1	残炭量/%
BPDFA	200	259	7.7	405	6.9	—	—	39.1
POCFA	190	250	11.6	—	—	—	—	40.0
DPCFA	180	220	5.3	255	9.2	580	2.8	39.5
DFAPO	180	323	3.0	529	1.9	—	—	48.1

样品	T_{5 %}/℃	T_max1 /℃	R_max1/%·min^-1	T_max2 /℃	R_max2/%·min^-1	残炭量/%
PA6	390	450	44.0	—	—	2.5
PA6/8 %BPDFA	327	392	32.3	—	—	4.1
PA6/8 %POCFA	305	403	28.3	—	—	5.8
PA6/8 %DPCFA	310	403	30.8	—	—	7.0
PA6/8 %DFAPO	334	372	5.8	423	21.0	7.3

样品	T_{5 %}/℃	T_max1 /℃	R_max1/%·min^-1	T_max2 /℃	R_max2/%·min^-1	残炭量/%
PA6	390	450	44.0	—	—	2.5
PA6/8 %BPDFA	327	392	32.3	—	—	4.1
PA6/8 %POCFA	305	403	28.3	—	—	5.8
PA6/8 %DPCFA	310	403	30.8	—	—	7.0
PA6/8 %DFAPO	334	372	5.8	423	21.0	7.3

样品	LOI/%	UL94 （3.2 mm）
样品	LOI/%	t₁/t₂	滴落	是否点燃	等级
PA6	20.7	9.8/2.4	严重	是	V⁃2
PA6/5 %BPDFA	23.0	9.2/1.4	严重	是	V⁃2
PA6/8 %BPDFA	25.5	5.0/1.6	较少	是	V⁃2
PA6/10 %BPDFA	23.8	2.0/1.0	较少	是	V⁃2
PA6/5 %POCFA	23.8	6.2/1.4	较少	是	V⁃2
PA6/8 %POCFA	24.8	4.4/1.2	较少	是	V⁃2
PA6/10 %POCFA	24.0	6.4/4.6	严重	是	V⁃2
PA6/5 %DPCFA	26.5	1.3/1.1	较少	是	V⁃2
PA6/8 %DPCFA	28.3	0.7/0	较少	否	V⁃0
PA6/10 %DPCFA	26.2	1.0/0.4	较少	是	V⁃2
PA6/5 %DFAPO	22.5	15.0/6.8	较少	是	V⁃2
PA6/8 %DFAPO	24.3	12.8/4.3	较少	是	V⁃2
PA6/10 %DFAPO	23.7	9.4/4.4	较少	是	V⁃2