The invention relates to a preparation method of melt spun high-strength high-modulus
polyvinyl alcohol fibers. The method comprises the following steps of: mixing
polyvinyl alcohol and water uniformly for fully swelling; adding the fully swollen
polyvinyl alcohol to a double screw extruder for full fusion and then
extrusion, and the fused
mass trickle is subjected to
air blast cooling to form nascent fibers; and the obtained nascent fibers are subjected to
drying by a hot-air oven, multistage drawing and tension
heat setting to form polyvinyl
alcohol fibers. The preparation method of polyvinyl
alcohol fibers provided by the invention has the beneficial effect that as only water is used for plasticization, through
hydrogen bond complex formed between water molecules and polyvinyl
alcohol molecules,
melt spinning and high stretching of polyvinyl alcohol are achieved; the polyvinyl alcohol fibers with excellent
mechanical property are prepared from general-grade polyvinyl alcohol; relevant complex process steps of coagulating bath and the like in the traditional wet
spinning method are not needed, the production process is simple, and environmental
pollution is small, and the production cost is low. The polyvinyl alcohol
fiber prepared by the method has the advantages of controllable
fiber number, high strength and high modulus, and the fibers can be widely applied to the field of civil work concrete.