Construction of PAN composite fibers with flame retardant, smoke suppression and enhanced mechanical properties based on self-assembled supramolecular network

To fabricate polyacrylonitrile (PAN) composite fibers with superior flame retardancy, smoke suppression and enhanced mechanical properties, a novel water insoluble biomass-based flame retardant, TPPA@PAO, was synthesized, which was then blended with PAN spinning solution and Co2+ solution was used as the coagulation bath to prepare modified PAN composite fibers (TPPA@PAO-Co/PAN). The elongation at break and tensile strength of TPPA@PAO-Co/PAN increased by 36.5 % and 45.4 % due to the formed three-dimensional crosslinked supramolecular network among TPPA@PAO, Co2+ and PAN. Furthermore, the limiting oxygen index of TPPA@PAO-Co/PAN increased from 17.3 % of the control PAN to 33.7 %. The peak of heat release rate, total heat release, peak of smoke production rate, total smoke production and CO production rate were reduced by 78.1 %, 63.5 %, 81.1 %, 85.0 % and 73.1 %, respectively. The work developed a novel approach for fabricating PAN composite fibers with simultaneous flame retardant, smoke suppression and enhanced mechanical properties, expanding its application field.