Graphene Oxide–Pretreated Waste Medical Mask Microfiber-Reinforced Cement Composites: Frost Damage Modeling and Chloride Migration

Abstract

Proper disposal of waste medical masks has become increasingly urgent in order to protect the ecosystem. Our exploratory study has proven the feasibility of producing waste mask microfibers (WMMF) and pretreating them with graphene oxide (GO) to enhance the strengths of cement composites. This study further explored the resistance of designed WMMF/GO-WMMF mortar (w/c of 0.40) to chloride migration and frost damage, to address the knowledge gap related to durability. The GO-pretreated WMMF improved the chloride migration resistance (by ∼50%) and the freeze–thaw resistance (by ∼20%), likely due to the tortuosity-increasing, hydration-accelerating, and hydrates-regulating roles of GO in the cementitious material. The microscopic investigation, including backscatter electron imaging, scanning electron microscopy, and thermogravimetric analysis, shed light on the mechanistic roles of GO and WMMF in cement composites. In addition, the two-parameter Weibull distribution was employed to model the frost damage and compare the remaining capacity of freeze–thaw resistance of the three designed mortar samples at the same reliability level; the Bayesian method was also utilized to model the uncertainty during the cyclic freeze–thaw process.