Material behaviourThe effect of the moisture content on the curing characteristics of an epoxy matrix in the presence of nanofibrous structures

This paper investigates the effect of polyamide 6 (PA 6) nanofibres and microfibres, as well as the effect of moisture present in these structures, on the curing kinetics of a diglycidyl ether of bisphenol A (DGEBA)-methylenedianiline (MDA) system. Modulated temperature differential scanning calorimetry measurements show that the initial reaction rate follows a linearly increasing trend as a function of the moisture content present in the nanofibrous structures. Compared to PA 6 microfibrous structures, incorporating PA 6 nanofibrous structures exposed to the same humidity resulted in a higher initial reaction rate, which is in agreement with the higher water absorption of the nanofibrous structure, measured with differential vapour sorption. Overall, the nanofibres themselves affect the curing characteristics, and the moisture present in the structures enhances this effect.