Structure and properties of high temperature resistant flame-retardant poly (phenylene-1,3,4-oxadiazole) (POD) fibers

The research development in poly(phenylene-1,3,4-oxadiazole)(POD) fibers at home and abroad was discussed.The functional monomers containing phosphorus or halogen were copolymerized with POD for improving the crystalline grade and flammability of the POD fibers,whose LOI can be up to 30 or above.The influence of coagulation bath conditions on the aggregation state,morphology and mechanical properties of the POD fibers was investigated,and it was found that aqueous sulfuric acid solution 40%-50% is the best dosage for the coagulation bath.Compared with other heat resistant fibers,POD fibers are superior to PPS,Nomex and Tanlon in high temperature resistance,and has better mechanical and dyeing properties,and better resistance to chemical corrosion,showing very good potential applications.