Correlation between the infiltration behaviors and nanoporous structures of silica gel/liquid energy absorption system

In this study, a silica gel/liquid nanoporous energy absorption system (NEAS) is developed and its infiltration behaviors are experimentally studied. The relation between the compressive pressure and volume of the silica gel/liquid NEAS is theoretically derived by assuming the accumulative infiltration of liquid to silica gel from large pores to small pores under quasi-static compression, which agrees with the experimental results very well. Besides, the infiltration behaviors of silica gel/liquid NEAS can be further tuned by sodium chloride (NaCl) concentration and the infiltration pressure increases almost linearly with NaCl concentration. This work is the first study to quantitatively correlate the compressive pressure and nanoporous structures of silica gel during infiltration. The results presented herein show that not only the infiltration pressure of silica gel/liquid NEAS can be adjusted by NaCl concentration, but also the compressive pressure-volume curve can be tuned by the distribution of the size of the nanopore in silica gel, which may be beneficial for some applications of NEAS with special requirements of stress-strain relation, such as personal protection, vibration absorber, and volume memory materials. © 2019 Author(s).