Recycling polyester fiber with bio-based alginate fiber into fire-safety composite

Depleting fossil reserve and recycling troublesome synthetic fiber waste has become a global crisis when the indecomposable fibers prevail in every aspect of daily life. This work developed an economical and environmentally friendly opening-combing-needle punching technique that recycled polyester waste fibers with intrinsic nonflammable bio-based alginate fibers into a composite up to 50% of its weight. It had a > 26 flame retardancy index and a UL94 V-2 rating, in line with cone calorimeter test that had peak of heat release rate of 27.63 kW/m(2), 38% less than similar alginate fiber/recycled textile fiber composites. Also, the composite generated 27% less smoke in burning than PET fiber felt. Its fire proof mechanism was explored as the dominant charring effect that dense CaCO3 residue prevented the felt from burning and exchanging heat/radicals at all stages. It also received support from inert gas dilution of H2O evaporated from calcium alginate fiber and easily generated CO2, as well as the homogeneous structure of the composite, while the increased CO/CO2 ratio ruled out the possibility of chemical quenching of active radicals. Taken together, this research recycled synthetic waste fiber into an outstanding fire-proofing composite by a cost-effective and eco-friendly method, which could be a potential filler and construction materials.

Automated summary

This study developed an economical and environmentally friendly method to recycle polyester waste fibers and bio-based alginate fibers into a fire-proof composite. The composite showed high flame retardancy and had a strong fire-proof mechanism. It could be used as a potential filler and construction material.