碱-尿素体系两步法对纯亚麻纱线改性研究

Study on two-step modification of pure flax yarn by alkali-urea system

24Nm的纯亚麻纱线进行碱-尿素两步法预处理,考察氢氧化钠浓度、尿素浓度、碱处理时间、尿素处理时间、浴比对纱线断裂强力和断裂伸长率的影响。结果显示,最佳预处理工艺为:氢氧化钠浓度13%,尿素浓度5.5%,碱处理时间15min,尿素处理时间15min,浴比为1∶17.5。在此条件下处理后,亚麻纤维取向度和结晶度明显变小,纤维分子间作用力减小,纤维排列更整齐、紧密,纱线的断裂强力下降,断裂伸长率增大。

24 Nm pure flax yarn was pretreated by alkali-urea two-step process,the influence of sodium hydroxide concentration,urea concentration,alkali treatment time,urea treatment time and bath ratio on yarn breaking strength and breaking elongation were investigated.The results show that the optimal pretreatment process parameters are sodium hydroxide concentration 13%,urea concentration 5.5%,alkali treatment time 15 min,urea treatment time 15 min and bath ratio 1∶17.5.Under this condition,after treatment,the orientation degree and crystallinity of flax fiber itself have obviously decreased,the intermolecular force of fiber has decreased,and the fiber arrangement is more orderly and tight,the breaking strength of the yarn decreases and the breaking elongation increases.