超薄膨胀型钢结构防火涂层的耐湿热性能  

Effects of Aging on Insulative Properties of Intumescent Coating for Steel Elements

作　　者：王玲玲[1] 李国强[1] Y．C．WANG 

机构地区：[1]同济大学土木工程学院,上海200092 [2]曼彻斯特大学土木、力学与航空学院,曼彻斯特M139PL

出　　处：《建筑材料学报》2011年第1期36-40,共5页Journal of Building Materials

基　　金：国家自然科学基金资助项目(50728805)

摘　　要：为考察超薄膨胀型钢结构防火涂层的防火隔热性能在某一特定环境下随使用时间的变化规律,对36个试件进行了人工加速老化试验和隔热性能试验.结果表明:高湿度环境下,涂层阻燃体系中的亲水性物质(如APP)会迁移到涂层表面而被溶解,使阻燃体系的组分和配比发生变化,导致高温下阻燃体系的膨胀受阻,从而影响到膨胀倍率和膨胀层内部结构,最终导致膨胀层等效导热系数变大;1,2 mm涂层试件的等效导热系数随老化时间总体上呈现出相同的变化规律,与0次循环试件相比,2,4次循环试件涂层的λ仅增大了1.0%左右,21次循环试件涂层的λ增大了30.0%,与21次循环试件相比,42次循环试件涂层的λ仅增大了3.0%左右,表明经过21次循环以后,涂层已达到一个稳定状态.In order to understand how the thermal properties of intumescent coating change with time in certain environment,accelerated ageing tests and fire resistance tests were carried out on 36 steel specimens coated with intumescent coating,of which 18 specimens were applied with intumescent coating of 1 mm thick and the other 18 with that of 2 mm thick.The experimental results is presented with particular focus on the effects of the various cycles of accelerated aging on the effective thermal insulation of the coating.It is concluded that under the accelerated aging regime in this study,the hydrophilic components APP and PER move to the surface of the coating and can be dissolved by moisture,so that the intended chemical reactions of these components to form an effective intumescent char are hindered.Intumescent coating thickness has little influence on the accelerated aging test results.Compared to the specimens without accelerated aging,the specimens that went through 2 and 4 cycles of accelerated aging show little degradation of thermal protection performance.However,the specimens after 21 cycles and 42 cycles of accelerated aging show considerable degradation in their fire protection performance with much higher effective thermal conductivity. The effective thermal conductivity was about 30.0%higher.Furthermore,the fire protection properties of the intumescent coating after 21 and 42 cycles of accelerated ageing test are similar,indicating that the intumescent coating becomes stable after a long period exposure to environmental condition.

关 键 词：超薄膨胀型钢结构防火涂层 老化 隔热性能 人工加速老化试验 等效导热系数 

分 类 号：TU545[建筑科学—建筑技术科学]