The potential safety hazard associated to commonly used flame retardant chemicals generates a strong demand for new, sustainable, and high performing solutions to reduce the fire threats of widespread polymer foams. In this work, the production of self‐extinguishing, nonignitable, and flame resistant flexible polyurethane foams by means of simple layer‐by‐layer assembly of graphene oxide nanoplatelets is reported. The process builds a protective exoskeleton that completely wraps the complex 3D structure of the foam and is capable of stopping flame spread in flammability tests and preventing ignition when exposed to heat fluxes typical of developing fires. In addition, treated foams are found able to withstand the penetration of a flame torch, successfully protecting the unexposed side from thermal decomposition for more than 6 min. The outstanding temperature gradient greater than 500 °C cm⁻¹ achieved through the foam thickness makes the performances of these foams comparable to those of a silica aerogel, while maintaining excellent flexibility and toughness. The results reported in this paper represent a tremendous opportunity for the production of a novel class of organic and flexible foams, capable of ensuring unprecedented fire safety properties while relying on an easy, green, and straightforward approach to material design.

中文翻译：

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氧化石墨烯外骨骼可产生自熄，不可燃和阻燃的柔性泡沫：机械上坚韧的无机气凝胶替代品

与常用的阻燃剂化学品相关的潜在安全隐患引起了对新型，可持续和高性能解决方案的强烈需求，以减少广泛的聚合物泡沫的火灾隐患。在这项工作中，报告了通过氧化石墨烯纳米片的简单逐层组装来生产自熄，不可燃和阻燃的柔性聚氨酯泡沫。该过程可建立保护性外骨骼，该外骨骼完全包裹泡沫的复杂3D结构，并能够在可燃性测试中阻止火焰蔓延，并在暴露于发生火灾的典型热流中时能够防止着火。另外，发现处理过的泡沫能够承受火焰的渗透，成功地保护未暴露的一侧免受热分解的影响超过6分钟。通过泡沫厚度获得的^-1使这些泡沫的性能可与二氧化硅气凝胶相媲美，同时保持了出色的柔韧性和韧性。本文报道的结果为生产新型的有机和软质泡沫提供了巨大的机会，该有机泡沫能够在依靠简单，绿色和直接的材料设计方法的同时确保空前的防火性能。