化学气相沉积SiO_(2)改性阻燃聚氨酯泡沫的制备及其性能

Preparation and Properties of SiO_(2) Modified Flame-retardant Polyurethane Foams by Chemical Vapor Deposition

有机保温材料广泛应用于建筑节能,但有机保温材料极易燃烧。传统阻燃方法在提高阻燃性能的同时会牺牲有机保温材料的保温性能或力学性能。因此,提高其防火安全性能的同时保留其优异的隔热性能是亟需解决的问题。报道了一种高效、温和的脉冲化学气相沉积(Pulsed CVD)方法,在硬质聚氨酯泡沫表面沉积SiO_(2)纳米层实现阻燃。改性后的阻燃聚氨酯复合材料保留了闭孔结构,导热系数测试结果为30.3 mW/(m·K)。阻燃性能测试结果表明,极限氧指数大幅提高至29.7%,通过了垂直燃烧V-0等级测试。阻燃机理分析结果表明,SiO_(2)促进了表面成炭阻燃过程,形成了更稳定有效的阻燃炭层结构。

Thermal insulation materials,especially polymeric materials,have been widely used in buildings to reduce energy consumption,but raditional polymeric thermal insulation materials are easily ignited.However,traditional methods will sacrifice the thermal insulation properties or mechanical properties of polymeric thermal-insulation materials while improving the flame retardant properties.Therefore,it is an urgent task to improve its fire safety performance while retaining its excellent heat insulation performance.The work reported an efficient and mild strategy of pulsed chemical vapor deposition(Pulsed-CVD)to generate the SiO_(2) nano layer on the rigid polyurethane foams to achieve flame-retardancy.The SiO_(2)/PUF showed closed-cell structure with extra-ordinary thermal conductivity of 30.3 mW/(m·K)and the value of limited oxygen index(LOI)substantially increased to 29.7%with silica nano layers.The mechanism of the enhanced flame retardancy highly related to the formation of stable chars by SiO_(2) nano layers.