Melt spinning method for high-strength high-modulus polyvinyl alcohol fiber

Abstract

The invention relates to a melt spinning method for a high-strength high-modulus polyvinyl alcohol fiber, comprising the following steps: uniformly mixing polyvinyl alcohol, water and an amide compound, and then, sufficiently swelling; adding the sufficiently swelled polyvinyl alcohol into a twin screw extruder, sufficiently melting, then extruding, and cooling the melt trickle through air blowing to form a nascent fiber; and drying the prepared nascent fiber through a hot-air oven, and then carrying out multistage stretching and tension heat setting to form the polyvinyl alcohol fiber. By using the preparation method of the polyvinyl alcohol fiber provided by the invention, melt spinning and high stretching of the polyvinyl alcohol are realized through hydrogen bond compounding among molecules of the water, the amide compound and the polyvinyl alcohol, and the prepared polyvinyl alcohol fiber has excellent mechanical property; and the melt spinning method is simple in production process, little in environment pollution and low in production cost; and the polyvinyl alcohol fiber prepared by using the method has the advantages of controllable fineness, high strength and high modulus so as to be widely applied to the field of civil engineering concrete.

Description

technical field [0001] The present invention relates to a kind of melt-spinning method of high-strength and high-modulus polyvinyl alcohol fiber, in particular to a preparation method of high-strength and high-modulus polyvinyl alcohol coarse denier fiber for civil engineering, specifically a high-strength and high-modulus polyvinyl alcohol (PVA) Process for preparing coarse denier fiber by melt spinning. Background technique [0002] In order to improve the shortcomings of concrete such as poor tensile performance, crack resistance and poor ductility, the research on adding synthetic fibers to concrete to improve concrete performance has developed quite rapidly. At present, there are more researches on polypropylene fiber, polyethylene fiber, nylon fiber, polyester fiber, carbon fiber, aramid fiber, polyvinyl alcohol fiber, etc. Among them, polypropylene monofilament fiber is currently widely used in the market because of its low price, high chemical corrosion resistance, ...

AI Technical Summary

Problems solved by technology

Therefore, in order to realize the coarse denier of polyvinyl alcohol fibers, there are also certain research results in the melt spinning of polyvinyl alcohol: Chinese patent CN101899722A swells polyvinyl alcohol with water, extrudes after dissolving by a single screw, and passes through the freezing liquid Coagulation forms polyvinyl alcohol coarse denier fibers, but there are still the disadvantages of long production process and high cost through the coagulation bath into filaments; the details of plasticized melt spinning coarse denier fibers are disclosed in the Chinese invention patent publication authorized announcement number CN1786302A "A method for preparing high-performance polyvinyl alcohol fiber", which is melt-spun by adding a small molecule modifier and polyvinyl alcohol to form an intermolecular compound, but there are many kinds of small molecule additives, complicated extraction, and high cost.