Two-staged sorption isotherm of a nanoporous energy absorption system

To selectively absorb impact energy, the profiles of sorption isotherms of protection systems must be adjusted in a broad spectrum. In this article, a N-Lauroylsarcosine sodium salt (sarcosyl) of intermediate molecular size is used to control the pressure induced infiltration of a nanoporous silica. The experimental result shows that the infiltration plateau of this system is two-staged; that is, not only the activation pressure but also the infiltration volume can be modified. It is noticed that the sarcosyl molecule demands a "free volume" to enter a nanopore. The free volume size decreases nearly linearly as the sarcosyl concentration increases.