Rizvi Ali, Chu Raymond K M, Park Chul B
Microcellular Plastics Manufacturing Laboratory, Department of Mechanical and Industrial Engineering , University of Toronto , 5 King's College Road , Toronto , Ontario M5S 3G8 , Canada.
ACS Appl Mater Interfaces. 2018 Nov 7;10(44):38410-38417. doi: 10.1021/acsami.8b11375. Epub 2018 Oct 29.
The requirement of energy efficiency demands materials with superior thermal insulation properties. Inorganic aerogels are excellent thermal insulators, but are difficult to produce on a large-scale, are mechanically brittle, and their structural properties depend strongly on their density. Here, we report the scalable generation of low-density, hierarchically porous, polypropylene foams using industrial-scale foam-processing equipment, with thermal conductivity lower than that of commercially available high-performance thermal insulators such as superinsulating Styrofoam. The reduction in thermal conductivity is attributed to the restriction of air flow caused by the porous nanostructure in the cell walls of the foam. In contrast to inorganic aerogels, the mechanical properties of the foams are less sensitive to density, suggesting efficient load transfer through the skeletal structure. The scalable fabrication of hierarchically porous polymer foams opens up new perspectives for the scalable design and development of novel superinsulating materials.
对能源效率的要求需要具有卓越隔热性能的材料。无机气凝胶是优异的隔热材料，但难以大规模生产，机械性能脆，且其结构性能强烈依赖于密度。在此，我们报道了使用工业规模的泡沫加工设备可扩展地生成低密度、具有分级多孔结构的聚丙烯泡沫，其热导率低于市售的高性能隔热材料，如超绝缘聚苯乙烯泡沫塑料。热导率的降低归因于泡沫泡孔壁中多孔纳米结构对气流的限制。与无机气凝胶不同，这些泡沫的机械性能对密度不太敏感，这表明通过骨架结构实现了有效的载荷传递。分级多孔聚合物泡沫的可扩展制造为新型超绝缘材料的可扩展设计和开发开辟了新的前景。
