拉伸方法对高强高线密度PVA纤维结构性能的影响

Effect of Heat Drawing on Structure and Properties of High-strength PVA Monofilaments

聚乙烯醇经干湿法凝胶纺丝制得初生纤维后,采用不同的两级后拉伸方法,制得单纤线密度在200～300 dtex的高线密度PVA纤维。探讨了两级不同拉伸条件对PVA纤维结构和性能的影响。结果表明:一级拉伸热定型,有利于折叠链晶体的完善,一级拉伸后再经二级拉伸定型,纤维结晶更完善,水中软化点和纤维断裂强度分别达到116℃和11.5 cN/dtex。

High-strength PVA monofilaments were prepared by gel-spinning and tow-step heat drawing. The effect of different two-step heat drawing process on the structure and properties of high-strength PVA monofilaments were discussed. The results showed that： the heat-setting after primary stretching was benefical to the perfection of folded chain crystal, but went against the formation of extended chain crystal and orientation of molecular chain. The second drawing after primary stretching made the crystallization of fiber more perfect, the strength and soften point in water of fiber up to 11.57 CN/dt and 116℃, respectively.