Cellular structure design by controlling the dissolution and diffusion behavior of gases in silicon rubber

• Published in: The Journal of supercritical fluids 2022-07, Vol.186, p.105610, Article 105610
• Main Authors: Wang, Bo, Liao, Xia, Tang, Wanyu, Li, Shaojie, Jiang, Qiuyue, Yang, Jianming, Li, Junsong, Li, Ruosong, Tian, Chenxu, Li, Guangxian
• Format: Article
• Language: English
• Subjects: Anti-shrinking foam; Cellular design; Mixed gases; Silicon rubber
• ISSN: 0896-8446; 1872-8162
• DOI: 10.1016/j.supflu.2022.105610

In this work, the dissolution and diffusion behaviors of different supercritical fluids (SCFs) including CO2, N2 and their mixtures in silicon rubber were investigated by magnetic suspension balance (MSB) and a situ visualization system to trace the expansion of sample's volume. The results showed that the mixed gas in silicon rubber having an appropriate proportion could maintain the high solubility while obtaining relatively low diffusion coefficient. In addition, a processing strategy which utilized conjunctively the CO2 with high solubility and N2 with low diffusivity in silicon rubber was used to design the cellular structure and improve shrinking problem. The resulting silicon rubber foamed by mixed gas has a lowest density of 0.086 g·cm−3 and the problem of cell shrinking has been improved effectively. This approach widens silicon rubber's potential as a high-performance foam material and provides an idea for preparing ultra-light silicone rubber foam material. [Display omitted] •The solubility and diffusion behaviors of different supercritical fluids in silicon rubber were investigated in this paper.•A situ visualization system was attached to magnetic suspension balance (MSB) to trace the expansion of sample's volume.•The cellular structure of silicon rubber was designed by foaming agents with different solubility and diffusion coefficients.•A mixture of CO2 and N2 was used to prepare silicon rubber foam which could improve effectively cell shrinkage .