Rattanakawin Podchara, Yoshimoto Kenji, Hikima Yuta, Chandra Alvin, Hayakawa Teruaki, Tosaka Masatoshi, Yamago Shigeru, Ohshima Masahiro
Department of Chemical Engineering, Kyoto University, Kyoto 615-8510, Japan.
Department of Materials Science and Engineering, Tokyo Institute of Technology, Tokyo 152-8552, Japan.
ACS Macro Lett. 2020 Oct 20;9(10):1433-1438. doi: 10.1021/acsmacrolett.0c00475. Epub 2020 Sep 17.
Nanocellular polymer foams have shown significant potential for industrial applications because of their superior thermal, mechanical, and optical properties. Some of these properties may be further improved by enhancing the ordering of cell structures. However, it is challenging for conventional foaming methods to control both the cell size and ordering at the nanoscale. Here, we show an innovative method to produce highly ordered nanocellular polymer foams by incorporating the self-assembly of an asymmetric diblock copolymer with the UV-induced chemical foaming technique. The minor domains are designed to generate a gaseous compound from the partial cleavage of the functional group. It is demonstrated that the gas-producing reaction can be accelerated at a temperature low enough to prevent melting of the whole self-assembled template, by mixing a small amount of photoacid generator into the copolymer, followed by UV irradiation. The result is the production of polymer foams with the nanoscale cells highly aligned to the self-assembled domains.
纳米多孔聚合物泡沫因其优异的热性能、机械性能和光学性能而在工业应用中显示出巨大潜力。通过增强泡孔结构的有序性，其中一些性能可能会进一步提高。然而，传统的发泡方法在纳米尺度上控制泡孔尺寸和有序性具有挑战性。在此，我们展示了一种创新方法，通过将不对称二嵌段共聚物的自组装与紫外线诱导化学发泡技术相结合来制备高度有序的纳米多孔聚合物泡沫。次要区域被设计用于通过官能团的部分裂解产生气态化合物。结果表明，通过将少量光酸产生剂混入共聚物中，然后进行紫外线照射，在足够低的温度下可加速产气反应，以防止整个自组装模板熔化。最终得到的聚合物泡沫具有与自组装区域高度对齐的纳米尺度泡孔。
