材料期刊网

目的 探究SiO2气凝胶在绝热涂层中的应用,利用SiO2气凝胶的低导热系数、低密度、高孔隙率及低折射率等优异性质,提高涂层隔热性能和耐高温性能.方法 通过筛选不同类型的水性树脂和功能填料,选择吸热较少的树脂和隔热性能优异的填料作为绝热涂层的原材料.采用自制隔热装置以及导热系数测量仪,对添加不同质量分数SiO2气凝胶的绝热涂层的隔热性能进行研究,并采用XRD、FT-IR等多种分析手段,研究涂层加热到200、300、400℃时的物相结构和基团变化.结果 水性丙烯酸树脂含吸热基团较少,在相同光照条件下,平衡温度分别比聚氨酯树脂和环氧树脂低0.8℃和1.8℃,适宜作SiO2气凝胶绝热涂层的成膜物质.涂层隔热性能随SiO2气凝胶质量分数的增加呈先增强后减弱的趋势,当SiO2气凝胶质量分数为5%时,涂层的隔热性能最佳,同未添加SiO2气凝胶的涂层相比,最大温差可达12℃.随SiO2气凝胶质量分数的增加,涂层的耐高温性能提升,当SiO2气凝胶的质量分数为7%时,涂层能在400℃高温下保持良好的性能.结论 SiO2气凝胶对隔热涂层的隔热性能和耐高温性能有较大提升,对SiO2气凝胶涂层的多领域应用奠定了一定基础.

The work aims to explore application of SiO2 aerogel in thermal-insulating coating, and improve thermal insula-tion performance and heat resistance by taking advantage of its low thermal conductivity, low density, high porosity and low re-fractive index. Resin of lower heat absorptivity and filler of excellent thermal insulation performance were selected as raw mate-rials of thermal-insulating coating by screening different types of water-base resin and functional filler. Thermal insulation per-formance of thermal-insulating coatings with different mass fractions of SiO2 aerogel was studied with homemade thermal insu-lation device and thermal conductivity measuring instrument. Phase structure and group change of the coatings heated to 200, 300 and 400℃ were studied in FT-IR and XRD methods. Water-based acrylic resin contained less endothermic groups, and its equilibrium temperature was 0.8℃ and 1.8℃ lower than that of polyurethane resin and epoxy resin respectively in same illu-mination conditions. It was more suitable to be used as film-forming materials of SiO2 aerogel heat insulation coating. As mass fraction SiO2 aerogel increased, heat insulation performance first improved and then reduced. The heat insulation performance was the best when the SiO2 aerogel mass fraction was 5%, insulating performance and temperature might reduce by 12℃. Meanwhile, the heat insulation performance improved as the SiO2 aerogel increased. When the mass fraction of SiO2 aerogel was 7%, the coating could maintain good properties at 400℃ . SiO2 aerogel can improve the heat insulation performance and heat resistance of thermal-insulating coating significantly, laying the foundation of its multidisciplinary application.