An energy-absorbing polyelectrolyte gel matrix composite material

A novel polyacrylic acid gel matrix composite material functionalized by hydrophobic nanoporous silica particulates is developed. When subjected to a high pressure, water molecules can be released from the polyacrylic acid network and forced into the nanopores. Due to the exposure of the large pore surface to the nonwetting liquid, the system free energy increases significantly. As the pressure is removed, the water remains in the confining nanoenvironment, and thus the material is energy absorbing. The energy absorption efficiency is much higher than that of many conventional protective materials. (c) 2005 Elsevier Ltd. All rights reserved.