Synthesis Of Flame Retardant Containing Phosphorus And Nitrogen And Its Flame-retarded Application Of Cotton Fabrics

Cotton is one of the most important natural fibers with good performance in the textile field. It has gained increasing attention because of its excellent breathability, soft handle and good biocompatibility and biodegradability. However, cotton fabrics are easily flammable materials, which may lead to fire disaster and bring injury to lives and properties of human beings. Phosphorus-nitrogen containing flame retardants are halogen-free and difficult to migrate, emit very low smoke or toxic gases during combustion, and display good compatibility. Furthermore, the synergistic effect between phosphorus and nitrogen has been studied and showed superior properties in the application of flame retardant. In this study, cotton fabrics were modified with the synthesized flame retardants containing phosphorus and nitrogen, and then the flame retardant properties of the coated cotton fabrics were investigated. The influence of flame retardant on the performance of cotton fabric treated with electron beam irradiation process and traditional pad-dry-cure process was also investigated.Firstly, diethyl 3-(triethoxysilanepropyl) phosphoramidate(DTP) was synthesized successfully and attached onto cotton fabrics. The obtained flame-retarded cotton fabrics were characterized by SEM and XPS. Thermal property, flame retardant property and mechanical property were evaluated. Secondly, water-soluble flame retardant PDTP was obtained by the hydrolysis polymerization of DTP and was coated onto cotton fabrics. SEM and XPS were used to characterize the coated cotton fabrics. Thermal property, flame retardant property and mechanical property were also determined. Thirdly, in order to investigate the influence of flame retardant on the performance of cotton fabric treated through electron beam irradiation process and traditional pad-dry-cure process, DMPP was bonded onto cotton fabrics by electron beam irradiation process and pad-dry-cure process. SEM and XPS were used to characterize the coated cotton fabrics. Thermal property, flame retardant property and mechanical property were also investigated.The results demonstrated that the treated cotton fabrics showed great flame retardant property. Vertical flammability test and limiting oxygen index indicated that the cotton fabrics treated with PDTP showed greater flame retardant property than cotton fabrics treated with DTP. When the concentration was 30%, LOI of the cotton fabrics treated with PDTP was 32.0% while LOI of the cotton fabrics treated with DTP was just 29.1%. Mechanical properties of the two kinds of flame retardant treated cotton fabrics declined in some degree. Meanwhile, when the concentration was 30%, the LOI of EB-cotton and PDC-cotton were30.2% and 28.7%, respectively. Cotton fabrics treated with DMPP via electron beam irradiation process displayed better flame retardant property and mechanical property than that treated with via traditional pad-dry-cure process.