火焰环境下隔热内衬气凝胶球粒的耐热特性

为减少或避免消防员在火灾救援活动中遭受热伤害,以SiO2气凝胶粉末、聚乙烯醇和水为原材料,制备一种用于充填消防服隔热内衬的气凝胶球粒,其压缩变形率在15.83%以内。首先探究气凝胶球粒的耐热机制及热传导影响因素;然后对其进行微观结构表征和比表面积测试;最后在不同火焰温度下测试耐热特性。结果表明:在同一测试温度下,气凝胶球粒表面变黑程度越大,所需时间越长;温度低于168.2℃时,球粒表面最大变黑程度为80%;随着温度的升高,球粒达到同一变黑程度所需的时间逐渐减少;热重试验得出气凝胶球粒的失重率比气凝胶粉末小。

Heat resistance characteristics of aerogel spherules for thermal insulation lining in flame environment

In order to reduce or prevent heat injuries for firefighters in rescue activities,with Si O2 aerogel powder,polyvinyl alcohol and water as raw materials,aerogel spherules,filling for thermal insulation lining of fire-protection suits,were developed,whose compression deformation rate was less than15.83%.Firstly,its heat-resistant mechanism and influencing factors of heat conduction were investigated.Then,microstructure was characterized and specific surface area was tested.Finally,heat resistance experiment was carried out at different flame temperatures.The results show that when at same testing temperature,the greater degree of blackening of its surface is,the longer it takes.When it is lower than168.2℃,the maximum blackening degree of surface is 80%.Along with increase of temperature,the time required to reach a certain blackening degree decreases gradually.It is also found that weight loss rate of aerogel spherules is smaller than that of aerogel powders.