Preparation of piperazine pyrophosphate @COF flame retardant and its flame retardant effect on epoxy resin

doi:10.19491/j.issn.1001-9278.2024.08.014

Abstract

Abstract:

A covalent organic framework （COF） was prepared by solution synthesis， and then the COF was coated on piperazine pyrophosphate （PAPP） to form PAPP@COF hybrid flame retardant， which was applied to epoxy resin （EP）. The effects of PAPP@COF hybrid flame retardants on the flame retardancy and smoke suppression of EP were analyzed by oxygen index meter， vertical combustion meter and cone calorimeter. The results indicated that the oxygen index of EP composite can reach 30.0 %， the peak heat release rate was 911.35 kW/m²， and the peak smoke release rate was 0.394 m²/s， which were 37.36 % and 34.27 % lower than that of pure EP by adding 2 phr PAPP@COF. PAPP@COF hybrid flame retardants have excellent flame retardancy and smoke suppression effects on EP， which provides a certain basis for the research of COF flame retardants.

Key words: epoxy resin, flame retardant, smoke suppression, piperazine pyrophosphate, covalent organic framework

CLC Number:

TQ320.4

WU Weihong, ZHANG Jing, ZHANG Ge, GENG Rongrong, QU Hongqiang. Preparation of piperazine pyrophosphate @COF flame retardant and its flame retardant effect on epoxy resin[J]. China Plastics, 2024, 38(8): 88-93.

Figures/Tables 10

References 19

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样品名称	T_{5 %}/℃	T_max%/℃	R_max/%·min^-1	C_{800 ℃}/%
COF	425.4	454.5	-1.1	67.27
PAPP	357.1	373.8	-8.7	43.78
PAPP@COF	390.7	431.1	-14.2	39.06

样品名称	T_{5 %}/℃	T_max%/℃	R_max/%·min^-1	C_{800 ℃}/%
COF	425.4	454.5	-1.1	67.27
PAPP	357.1	373.8	-8.7	43.78
PAPP@COF	390.7	431.1	-14.2	39.06

样品名称	LOI/%	UL 94
样品名称	LOI/%	有焰燃烧时间（t₁）/s	有焰燃烧时间（t₂）/s	滴落
EP	23.7	—	—	无等级
EP/PAPP 1	24.6	24.7	4.2	V⁃1
EP/PAPP 2	25.5	27.7	36.6	V⁃1
EP/PAPP@COF 1	25.2	—	—	无等级
EP/PAPP@COF 2	30.0	29.0	2.5	V⁃1

样品名称	LOI/%	UL 94
样品名称	LOI/%	有焰燃烧时间（t₁）/s	有焰燃烧时间（t₂）/s	滴落
EP	23.7	—	—	无等级
EP/PAPP 1	24.6	24.7	4.2	V⁃1
EP/PAPP 2	25.5	27.7	36.6	V⁃1
EP/PAPP@COF 1	25.2	—	—	无等级
EP/PAPP@COF 2	30.0	29.0	2.5	V⁃1

样品名称	PHRR/ kW·m^-2	t_PHRR/ s	THR/ MJ·m^-2	PCOP/ g·s^-1	PCO₂P/ g·s^-1
EP	1 454.90	115	118.66	0.037	1.005
EP/PAPP 1	1 471.77	70	118.11	0.055	0.836
EP/PAPP 2	977.28	95	106.65	0.036	0.577
EP/PAPP@COF 1	1 363.87	110	118.13	0.043	0.842
EP/PAPP@COF 2	911.35	110	110.27	0.032	0.521