A Practical Valorization Approach for Mitigating Textile Fibrous Microplastics in the Environment: Collection of Textile-Processing Waste Microfibers and Direct Reuse in Green Thermal-Insulating and Mechanical-Performing Composite Construction Materials

Microplastic (MP) contamination is an urgent environmental issue to address. Fibrous microplastics (FMPs) are the principal MP type in air and have already been found human stool lung tissues. FMPs generated from lifecycle of synthetic blended textiles expected increase due fast fashion. Among textile processes, finishing fabrics estimated generate 5000 t/year waste fibers Italy, including FMPs. To limit spread, this paper suggests, for first time, direct collection microfibers reuse designing thermal-insulating mechanical-performing fiber-reinforced cementitious composites (FRCs). The were thoroughly characterized (size, morphology, composition, density), their use FRCs was additionally evaluated by considering water absorption release capacity. Untreated, water-saturated, NaOH-treated considered up 4 wt%. Up a +320% maximum bending load, +715% toughness, −80% linear shrinkage, double-insulating power Portland cement observed increasing microfiber contents. water-saturated better enhanced toughness shrinkage reduction. Therefore, green performant composite construction materials obtained, allowing mitigation more than kg per ton paste. This great result FMP (i.e., 2–8 kg/day fallout Paris), that promising shortly-widely used materials.