Investigation of toughening behavior of epoxy resin by reinforcement of depolymerized latex rubber

Abstract An epoxy resin (EP) matrix has been modified with depolymerized natural rubber (DNR). The 0.5, 1.0, 1.5, 2.0, and 2.5 wt% DNR-filled epoxy were used for the present investigation. The primary aim of this development is to scrutinize the mechanical properties of such cured epoxy filled with DNR. When the rubber content was low, the mechanical strength was low and the free volume of DNR in epoxy matrix was less. With the increase in rubber content, the free volume of rubber in the composite increases and the mechanical strength increases; however, after a specific weight percentage of rubber, if we increase the amount of rubber, the mechanical strength decreases and the free volume of rubber in the composite increases quickly, but with the increase in DNR weight percentage in epoxy matrix, the hardness decreases. The scanning electron microscopy (SEM) results justified the results obtained from the mechanical tests.