Enhanced stiffness, strength and energy absorption for co-continuous composites with liquid filler

In this work the quasi-static compressive behaviors of the co-continuous glassy polymer/liquid composites are studied. Due to the presence of liquid filler, the stiffness, yield strength and energy absorption of co-continuous composites are significantly enhanced, which comes from the additional support of liquid filler and the lateral expansion of the glassy polymer. The influence of different volume fraction of liquid filler from 0.4 to 0.7 and different geometric structures of the glassy polymer, namely simple cubic (SC) lattice, face-centered-cubic (FCC) lattice, and body-centered-cubic (BCC) lattice, is investigated. Here, SC lattice structure is the most stretch-dominated structure during compression which has the highest stiffness, yield strength, and energy absorption. A general power law can be used to describe the relations of effective elastic modulus, yield strength, and energy absorption to the volume fraction of glassy polymer, which shows almost the same power indices for the same geometric structure. These results provide guidelines for engineering and tailoring the nonlinear mechanical behavior and energy absorption of co-continuous composites for a wide range of applications and further creating multifunctional materials.