Phytic Acid/phosphoric Acid Derivatives Flame Retardant Modified Lyocell Fiber And Cotton/Lyocell Blended Fabric

Lyocell fiber is a kind of new green and environment-friendly regenerated cellulose fiber.Cotton/lyocell blended fabric possesses many excellent characteristics such as mechanical properties,drape,moisture absorption and air permeability.However,the flammability of lyocell fiber and blended fabric is restricted in many areas of use.Therefore,it is of great significance to improve the flame retardancy of Lyocell fiber and cotton/lyocell blended fabric.Based on people's pursuit of green and environmental protection concept,this paper firstly used natural biological compound phytic acid(acid source)with high phosphorus content,reacting with neopentyl glycol(carbon source)and urea(gas source)to synthesize a green intumescent flame retardant,new pentaerylene glycol ammonium phytate salt(NPGPU).NPGPU was applied to the flame retardant finishing of lyocell fiber by the pad-dry-cure finishing process,and the environmentally friendly flame retardant lyocell fiber was prepared.The thermal stability of flame retardant lyocell fiber was studied by thermogravimetric analysis.The combustion performance of flame retardant lyocell fabric was analyzed by vertical combustion,cone calorimeter and limiting oxygen index(LOI).The results indicate that the initial decomposition temperature of lyocell fiber treated with NPGPU decreased by 177.1 ?,and the carbon residue increased by 21%.The LOI of treated lyocell fiber increased from 17% to 47.6%,and after 25 washing cycles,the LOI was 28.8%,showing excellent flame retardant performance.Secondly,based on the classical phosphoric acid/urea system,a new intumescent flame retardant,ammonium neopentyl glycol diphosphate(ANPGP),was prepared.Cotton/lyocell blended fabric with excellent flame retardant properties was prepared by the pad-dry-cure finishing process.The results showed that the ANPGP cotton/Lyocell blended fabric had excellent carbon formation and flame retardant properties.The carbon residue increased by 25%,the LOI increased from 19% to 44.3%,and after 30 washing cycles,the LOI was 27.2%.Compared with lyocell fiber treated with NPGPU,the washing times of cotton/lyocell blended fabric treated with ANPGP improved by 5 times.