Synthesis, physical-mechanical properties and fire behaviors of polyurethane foam with reactive flame retardant and expandable graphite

doi:10.11949/j.issn.0438-1157.20151564

Abstract

Abstract:

Flame retardant polyurethane foams have been synthesized by using a new reactive flame retardant hexakis (4-diethyl phosphate hydroxymethyl phenoxy) cyclotriphosphazene (HPHPCP) and expandable graphite (EG). The effects of flame retardants on physical-mechanical properties, thermal stability and fire performances were investigated. In particular, the fire behaviour of the foams was studied by the oxygen index and UL-94 burning test. The results showed that the density of flame retardant foams increased with flame retardant compound. The compressive strength increased first and then declined with the decrease content of HPHPCP. However, an increase in the content of expandable graphite caused a worsening of insulating properties of PUF. The presence of HPHPCP mixture with EG brought an overall improvement in the thermal stability and fire behavior. The initial decomposition temperature (T_10%), maximum decomposition temperature (T_max) and char residues at 700℃ increased with increasing content of EG in mixture flame retardant. Moreover, the oxygen index (OI) increased in a linear way and all flame retardant PUFs can pass UL-94 HF-1 and V-0 rating.

Key words: foam, synthesis, preparation, expandable graphite, flame retardancy

摘要：

将反应型阻燃剂六(4-磷酸二乙酯羟甲基苯氧基)环三磷腈(HPHPCP)和可膨胀石墨(EG)复配,制备了阻燃聚氨酯泡沫,详细研究了复配阻燃剂对聚氨酯泡沫的物理力学性能、热稳定性以及阻燃性能的影响。结果表明,阻燃聚氨酯泡沫的密度和热导率随着复配阻燃剂中EG含量的增加而升高;压缩强度随着EG含量的增加呈现先增加后降低的趋势。热失重表明复配阻燃剂大大提高了聚氨酯泡沫的热稳定性。聚氨酯泡沫的初始分解温度(T_10%)从212.9℃,分别提高到222.0、231.2和243.2℃;700℃残炭量从7.6%分别提高到26.3%、31.6%和37.9%。聚氨酯泡沫的阻燃性能随着复配阻燃剂中EG含量的增加而提高。阻燃聚氨酯泡沫的极限氧指数从19%提高到29%,均能通过UL-94水平燃烧HF-1等级和垂直燃烧V-0等级。

关键词: 泡沫, 合成, 制备, 可膨胀石墨, 阻燃

CLC Number:

O631

YANG Rong, QIAO Hong, HU Wentian, XU Liang, SONG Yan, LI Jinchun. Synthesis, physical-mechanical properties and fire behaviors of polyurethane foam with reactive flame retardant and expandable graphite[J]. CIESC Journal, 2016, 67(5): 2169-2175.

杨荣, 乔红, 胡文田, 许亮, 宋艳, 李锦春. 反应型磷氮阻燃剂/可膨胀石墨复配阻燃聚氨酯泡沫[J]. 化工学报, 2016, 67(5): 2169-2175.

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