Study on the Flame Retardant and Mechanical Properties of Wet-spun Poly(acrylonitrile-co-vinylchloride) Fibers with Antimony Trioxide and Zinc Hydroxystannate

To produce flame resistant poly(acrylonitrile-co-vinyl chloride) (PANVC) fibers (limiting oxygen index (LOI)> 28%) for flame retardant work wear, PANVC solutions containing antimony trioxide (ATO) and zinc hydroxystannate (ZHS) flame retardants at various composition ratios were wet spun using laboratory-scale equipment. The amount of ATO and ZHS added was determined to be 15 phr using the thin material vertical burning test. The LOI values of PANVC increased considerably from 27.9% to 33.1% with increasing ZHS composition ratio, but no significant synergistic effects were observed between ATO and ZHS. With increasing ZHS composition ratio, more densified structures of the char layer were observed after combustion. ZHS was found to be a more effective and suitable flame retardant for PANVC than ATO. The PANVC fibers had a round cross section and the ATO and ZHS particles were distributed uniformly in the PANVC fibers. The presence of ATO and ZHS particles decreased the tenacities of the pure PANVC fibers slightly.