Flameproof polyacrylonitrile fibre and method for preparing same

Abstract

The invention discloses a flame-proof polyacrylonitrile fiber and its manufacturing method. Said fiber comprises at least 5%-25% by polyacrylonitrile weight of APP flame retardant, or APP flame retardant treated by silane coupler or titanate coupler, furthmore, comprises pentaerythritol, bi-pentaerythritol and like polyhydric alcohol compound, which has a APP-to-polyhydric alcohol ratio ranging from 2 to 3.8 by wt / wt. The method for manufacturing said fiber includes: crossblending the flame retardant with the inorganic solvent spinning dope of polyacrylonitrile, which is obtained by one-step method or two-step method to prepare crossblending spinning dope, then spinning, washing, drafting and thermal sizing by using current technique of making acrylon with inorganic solvent spinning line. The invention applies cheap, non-poisonous and high efficient inorganic additive flame retardant APP to spin flame retardant acrylon, as a result, crossblending spinning dope with good spinnability and fiber with high flame retardancy is obtained.

Description

field of invention [0001] The invention relates to a flame-retardant fiber material—flame-retardant polyacrylonitrile fiber and a manufacturing method thereof, in particular to a flame-retardant polyacrylonitrile fiber containing ammonium polyphosphate flame retardant and spun by an inorganic solvent and a manufacturing method thereof. Background technique [0002] Polyacrylonitrile fiber (commonly known as acrylic fiber) has the advantages of high bulkiness, comfortable hand feeling, good heat retention, and easy dyeing. It is widely used in clothing, daily decorations, and industrial applications. But its biggest disadvantage is that it is easy to burn, and it produces highly toxic hydrogen cyanide, etc., so its application is limited in many occasions requiring flame retardancy. [0003] At present, there are three main methods for producing flame-retardant acrylic fibers in the world, namely finishing method, copolymerization method and blending method. The post-finishi...

AI Technical Summary

Problems solved by technology

However, the copolymerization method has the following disadvantages: compared with conventional acrylic fiber, the polymerization and spinning production process must be changed; when using inorganic solvent spinning, the flame retardant monomer content in the inorganic solvent-soluble interpolymer is generally lower than 20wt% ~25wt%, it is difficult to meet the flame retardant requirements, and when using organic solvents, although the flame retardant monomer content in the copolymer can be increased to more than 45wt%, it will cause heat resistance, light resistance, fiber dimensional stability and dyeability of the polymer Deterioration of excellent properties such as copolymers; water phase polymerization is generally used for the preparation of copolymers, but many flame retardant monomers such as vinyl halides have low water solubility and high volatility, which makes the polymerization reactivity and polymerization rate low, and also brings certain problems to production operations. difficulty

[0013] APP is an inexpensive, non-toxic, highly efficient, and widely used inorganic additive flame retardant. However, when it is used to spin flame-retardant acrylic fibers, it cannot be used well because it is insoluble in common organic solvents for polyacrylonitrile. Dispersed, it is difficult to use organic solvents for spinning; APP with a low degree of polymerization has good water solubility and is soluble in the usual inorganic solvent spinning stock solution of polyacrylonitrile, but it will cause a large amount of APP to be lost during the fiber manufacturing process, and the resistance of the obtained fibers Flammability and flame-retardant durability are poor; although APP with a high degree of polymerization overcomes the disadvantage that APP with a low degree of polymerization is easy to dissolve in water, it has low solubility or even insoluble in the usual inorganic solvent spinning stock solution of polyacrylonitrile. When blending spinning dope with solvent, APP fine powder not only cannot be uniformly and stably dispersed, but also produces large hard particles, which seriously affects the spinnability of blending spinning dope