Crosslinked polyvinyl alcohol fiber and method for producing the same

Abstract

The present invention relates to crosslinked polyvinyl alcohol raw cord and method for producing the same, and more particularly, to crosslinked polyvinyl alcohol fiber, in which PVA resin having a degree of polymerization of more than 1,000 and a degree of saponification of more than 97.0 mol % is dissolved in dimethyl sulfoxide, the solution is subjected to dry and wet gel spinning using methanol as a coagulation solution, drawn and thermally treated, the resulting polyvinyl alcohol drawn yarn with 500-3,000 deniers is twisted to produce a cabling yarn, the cabling yarn is plied into a 2-ply or 3-ply yarn to produce a raw cord, the raw cord is wound on a bobbin for crosslinking and crosslinked in an aqueous crosslinking solution containing an aromatic aldehyde compound and an acid catalyst. Moreover, the present invention relates to a crosslinker-introducing apparatus, which is used in the above method and can effectively induce the crosslinking reaction of the wound raw cord.

Description

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to crosslinked polyvinyl alcohol fiber and method for producing the same, and more particularly, to crosslinked polyvinyl alcohol fiber, in which PVA resin having a degree of polymerization of more than 1,000 and a degree of saponification of more than 97.0 mol % is dissolved in dimethyl sulfoxide (hereinafter, referred to as DMSO), the solution is subjected to dry and wet gel spinning using methanol as a coagulation solution, drawn and thermally treated, the resulting polyvinyl alcohol drawn yarn with 500-3,000 deniers is twisted to produce a cabling yarn, the cabling yarn is plied into a 2-ply or 3-ply yarn to produce a raw cord, the raw cord is wound on a bobbin for crosslinking and crosslinked in an aqueous crosslinking solution containing an aromatic aldehyde compound and an acid catalyst. Moreover, the present invention relates to a crosslinker-introducing apparatus, which is used...

AI Technical Summary

Benefits of technology

[0034] It is the key technical point of the present invention that the aromatic aldehyde capable of infiltrating only into the non-crystalline region of the drawn yarn is used as the crosslinker. Since the aromatic aldehyde is mainly infiltrated only into the non-crystalline region of the yarn, the tenacity of the drawn yarn can be prevented from being reduced due to the crosslinker.

[0035] The most important characteristic of the present invention is a crosslinking process. In general crosslinking, there is used a method wherein the crosslinker is dissolved in an organic solvent in an extraction process in order to infiltrate the crosslinker into the inside of the fiber. However, this crosslinker within the undrawn fiber causes a reduction in drawability in a thermal drawing step at high temperature above 200° C., so that the drawn yarn does not hav

Problems solved by technology

However, although the PVA fiber produced by this method has excellent mechanical properties, the PVA resin is dissolved in hot water with a high temperature above 100° C. or has reduced mechanical properties, due to the hydrophilicity of PVA resin itself.

Thus, it has many limitations for use in applications, such as tire cords which have the biggest market among the industrial fibers.

Although a very small amount of water is present in the inside of a tire, excess water can flow into the tire when the tire gets damaged.

Also, when the tire temperature is increased to 130° C. as a result of high-speed running of automobile, the water is thermally hydrated to cause damages to the PVA fiber, so that the stability of automobiles is endangered.

Thus, the PVA fiber according to the prior art could not be used as a tire reinforcement material without anxiety.

Also, since the high crystallinity of the PVA fiber results in a reduction in fatigue resistance when it is used for tire cords, this

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