Upcycling of polyester wastes blended bio-based alginate fiber to fire-safety composite applied in the construct field

A depleting fossil reserve and the troublesome recycling corresponding waste is worldwide problem. This work upcycled polyester waste fiber with intrinsic nonflammable bio-based alginate fiber via opening-combing-needle punching technique into a fire-proof building material to reduce waste disposal and carbon footprint. The composite was proved to generate minor amount of smoke and heat, and abundant nonflammable CO 2 and H 2 O in the pyrolysis process.With very limited flammable H 2 , CO and C 2 H 4 , those can be completely diluted by the nonflammable gases. Furthermore, the credible flame-retardant mechanism of fuel-dilution effect was proposed, that was the final formed Ca-C residual chars cooperating with larger number of nonflammable gaseous volatile employed as a natural barrier to impede the heat, O 2 and mass transfer, which can dramatically reduce the fire hazard. Taken together, this research recycled the waste chemical fiber into the outstanding fire-proofing composite applied in the construct field by a cost-effective and eco-friendly method.