Research On The Preparation And Properties Of The Blending Modification Fire-retardant Viscose Rayon

With the rapid development of the research and market need for textile fire-retardant material, the demands of fire-retardant performance, multi-functionality, environmental protection and durability for the fire retardant of fabrics are increasingly improved. Because of no halogen, high phosphorus-nitrogen proportion, easiness to be functional, the cyclotriphosphazene derivatives are the low toxicity, no halogen, smokeless, low pollution, washable, new-type multi-functional fire retardants. So far, there has no report on the fire-retardant viscose rayon with the phosphazene derivatives as fire-retardant additives in our country. In this article, a kind of phosphazene derivative which accords with the requirement for environment protection was synthesized as flame retardant. And it was applied to the preparation of fire-retardant viscose rayon. The newly fire-retadant viscose rayon has the advantages of no-halogen, high efficiency, durability and accords with the requirement for environmental protection compared with nomal fire-retardant viscose rayon. In this paper, the combustibility, thermal performance, the physics chemical property, mechanics performance and finishing characteristics of the fire-retardant viscose fiber were studied. The influence of react temperature, time and ratio of interactant of fatty alcohol sodium and hexachlorocyclotriphosphazene on the yield of hexa(alkoxy)cyclotri-phosphazene was studied by the method of orthotropic design, and the results showed the yield of hexa(alkoxy)cyclotriphosphazene could attain to 83.76% under the optimum condition. Infrared spectrum was employed to characterize and determine the structure of the compound. The vibration absorption peaks of -P-O-C were dectected at 1063.35 cm-1and 1009.08 cm-1 on the IR spectrogram showed that hexa(alkoxy)cyclotriphosphazene was obtained. The blending modification fire-retardant viscose rayon was prepared by the process of blending, spinning and post treatment. The combustibility and thermal stability of fire-retardant viscose rayon were evaluted by 45°Slope Burning Method, Limit Oxygen Index(LOI), Differential Scanning Calorimetry(DSC), Thermogravimetry(TG). The results indicated that modified fiber could reach the limit oxygen index fire-retardant standard(LOI≥28),and fire-retardant standard of Japan industry standard JIS 1091-77(Times of ignition ≥3 次). The data showed the fire-retardant rayon was a durable fire-retardant viscose rayon. The fiber's thermal degradation mechanism showed flame retardant had played the multi-role of catalytic dehydration and carbonization, condensation–phase and gas-phase flame retardance, heat absorption. Methods of micro-photography, Scanning Electron Microscope(SEM), static stretching and dyeing were used to investigate the fire-retardant viscose rayon's properties of morphological structure, physics chemical properties, moisture regains, mechanic properties and dyeing behavior. Compared with normal rayon, the fire-retardant viscose rayon prepared had the same skin-core structure and sectional form of saw tooth form, but the later exhibited more holes and more rougher surface than normal rayon. With the increasing of fire retardant added, the degree of crystallinity reduced gradually, and the moisture regains were among 12%-14%. The mechanic properties of the fiber sample indicated the fiber with less fire retardant content had higher initial modulus and breaking strength while the fibers with more fire retardant had lower breaking strength and poor extensibility. Comparing the dyeing behavior of the fiber with different fire retardant content, it was found that the dyeing rate increased, the rate of color fixing and final dye yield dropped withthe increasing of fire retardant content.