Synthesis of phosphorus-nitrogen flame retardant based on cyclophosphonate and its application on rigid polyurethane foam

doi:10.11949/0438-1157.20191000

Abstract

Abstract:

Flame retardant hexa (4-anilino-methylenephenoxy-diethyl phosphite) cyclotriphosphazene (HADPPCP) was synthesized with hexachlorocyclotriphosphazene, p-hydroxybenzaldehyde, aniline, diethyl phosphite. Then it was used to prepare flame-retardant polyurethane foam. HADPPCP has good thermal stability and char formation. The initial decomposition temperature in a nitrogen atmosphere is 191.9℃, and the residual carbon content at 700℃ is as high as 46.8%(mass) in nitrogen. The addition of HADPPCP improved the fire safety of polyurethane rigid foams. When adding 25%(mass) HADPPCP, the limiting oxygen index of rigid polyurethane foam increased from 18% to 25%. The peak heat release rate and total heat release of polyurethane foam decreased from 230 kW/m² and 20.1 MJ/m² to 213 kW/m² and 16.6 MJ/m², respectively. Moreover, the total smoke production decreased from 10.5 m² to 5.3 m². It suggested that HADPPCP was an efficient flame retardant for RPUF, which can not only decrease heat release rate, but also suppress the smoke release rate of RPUF during the combustion.

Key words: foam, synthesis, flame retardancy, malic acid based polyols, rigid polyurethane foam

摘要：

以六氯环三磷腈、对羟基苯甲醛、苯胺及亚磷酸二乙酯等原料，成功合成阻燃剂六（4-苯胺基次甲基苯氧基-亚磷酸二乙酯基）环三磷腈（HADPPCP），用于阻燃基于苹果酸多元醇的聚氨酯硬泡。HADPPCP具有良好的热稳定性和成炭性，氮气气氛下的初始分解温度为191.9℃，700℃时的残炭量高到46.8%（质量）。HADPPCP的加入可以改善聚氨酯硬泡的热稳定性、阻燃性能和燃烧行为。添加25%(质量)的HADPPCP可以将聚氨酯泡沫的氧指数从18%提高到25%，最大热释放速率和总热释放量分别从230 kW/m²和20.1 MJ/m²降低至213 kW/m²和16.6 MJ/m²，总产烟量从10.5 m²下降到5.3 m²。

关键词: 泡沫, 合成, 阻燃, 苹果酸多元醇, 硬质聚氨酯泡沫

CLC Number:

O 631

Mengdi LI, Bo WANG, Zhehui WANG, Ye ZHANG, Rong YANG, Jinchun LI. Synthesis of phosphorus-nitrogen flame retardant based on cyclophosphonate and its application on rigid polyurethane foam[J]. CIESC Journal, 2020, 71(4): 1871-1880.

李梦迪, 王波, 王哲慧, 张晔, 杨荣, 李锦春. 基于环三磷腈磷氮阻燃剂的合成及其在聚氨酯泡沫的应用[J]. 化工学报, 2020, 71(4): 1871-1880.

Figures/Tables 16

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Sample	PU-0%FR	PU-15%FR	PU-20%FR	PU-25%FR
malic acid based polyol	100	100	100	100
AK8805	2	2	2	2
PC-8	1	1	1	1
HCFC-141b	20	20	20	20
H₂O	1	1	1	1
HADPPCP	0	45.3	64.2	85.6
PM-200	132.7	132.7	132.7	132.7

Sample	PU-0%FR	PU-15%FR	PU-20%FR	PU-25%FR
malic acid based polyol	100	100	100	100
AK8805	2	2	2	2
PC-8	1	1	1	1
HCFC-141b	20	20	20	20
H₂O	1	1	1	1
HADPPCP	0	45.3	64.2	85.6
PM-200	132.7	132.7	132.7	132.7

Sample	Density/ (kg/m³)	Compressive strength/ kPa	Thermal conductivity/ (W/(m·K))
PU-0%FR	37	155	0.0227
PU-15%FR	38	122	0.0232
PU-20%FR	41	110	0.0253
PU-25%FR	46	105	0.0277

Sample	Density/ (kg/m³)	Compressive strength/ kPa	Thermal conductivity/ (W/(m·K))
PU-0%FR	37	155	0.0227
PU-15%FR	38	122	0.0232
PU-20%FR	41	110	0.0253
PU-25%FR	46	105	0.0277

T_5%/℃	T_50% /℃	T_max/℃			Residues at 700℃/%(mass)
T_5%/℃	T_50% /℃	Step1	Step2	Step3	Residues at 700℃/%(mass)
191.9	515.8	210.0	292.7	466.6	46.8