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Cotton fiber is a natural cellulose fibers. Because of its excellent moisture absorption, air permeability, the wearing comfort and the natural regeneration, thus occupies an important position in the fiber production and applications. Flammability of ordinary cotton fiber, however, can not meet the development needs of the application, thus limiting its potential applications. The thesis prevalent in the existing flame retardant finishing of cotton fiber durability formaldehyde release, for the synthesis of guanidine carbonate and phosphate flame retardant guanidine phosphate, and get the best synthesis conditions: participate in the reaction of guanidine carbonate phosphoric acid molar ratio of 1:1.5-1.8, between the pH value of the final product can be controlled at between 6-8, and applied to the non-durable flame retardant finishing of the cotton fabrics. Using infrared spectroscopy (IR) and to characterize the chemical structure of the flame retardant. GA159-1997 standard, respectively, non-durability of cotton and polyester-cotton fabric processing, and flame retardant properties studies have shown that cotton fabric L0I41 damage length 70mm smoldering continued burning 0s, and polyester-cotton fabric L0I39 damage length 80mm, smoldering, continued burning 0s. Non-durable flame retardant requirements. The guanidine phosphate the Zhijie activation reaction: in an acidic environment, guanidine phosphate, and cellulose in the hydroxyl group and acetic acid, using the ethanedioic the two carboxyl groups in the one with phosphoric guanidine imino amidation reaction occurs; another esterification of carboxyl group and the hydroxyl group of cellulose, this will be between Zhijie reaction. With permanent flame retardant finishing conditions. Permanent flame retardant finishing process factors affect the flame retardant properties of cotton fabrics, to determine optimal flame retardant finishing conditions: flame-retardant finishing solution for 150-300g / L, the phosphate content of 20-30g / L, a dip rolling, rolling rate of 90%, the drying temperature of 75 ° C, the baking temperature :130-150 ℃, baking time :25-35min. To test its flame-retardant durability, flame retardant finishing of cotton fabric, 30 times after soaping, limiting oxygen index of loss and vertical combustion performance test results: ruined length 123mm, limiting oxygen index LOI 32.2. Achieve permanent flame retardant finishing effect. Thermal analysis (TG-DTA), cone calorimeter (CONE) analysis of the the guanidine phosphate flame retardant cotton and polyester combustion process. By scanning electron microscopy (SEM) analysis of a variety of fabric combustion residues. Of guanidine phosphate flame retardant mechanism in the combustion process of the fabric. The results show that the introduction of the guanidine phosphate reduces the initial temperature of the pyrolysis of cotton fabric, but the pyrolysis rate is significantly reduced, significantly reduced in the heat release during the pyrolysis of the pyrolyzed product and exothermic strength temperature end point 700 ℃ The solid remaining was significantly improved. Although guanidine phosphate also reduces the initial pyrolysis temperature of the polyester-cotton fabric, but the pyrolysis rate is significantly reduced, 'pyrolysis process the pyrolyzed product exotherm and exothermic strength is significantly reduced, but at a temperature of end point 700 ° C when the solid The remaining increase in the rate is not as good as cotton fiber. The SEM images show that the carbon layer the surface of the foam by the flame retardant fiber, is the key to protect the substrate play a flame retardant effect, the higher the foaming ratio of the carbon layer, the better the flame retarding effect.
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