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

In this work, the dissolution and diffusion behaviors of different supercritical fluids (SCFs) including CO2, N-2 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 N-2 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.

Automated summary

This study investigated the dissolution and diffusion behaviors of different supercritical fluids in silicon rubber. It was found that a mixed gas with appropriate proportions could maintain high solubility while obtaining a low diffusion coefficient, leading to the design of cellular structures to improve shrinking issues. The resulting silicon rubber foam by mixed gas showed great potential as a high-performance foam material with improved cell shrinking.