Lyocell纤维纺丝浆粕溶解性的影响因素分析

为探究Lyocell纤维纺丝浆粕溶解性的影响因素,对4种不同的溶解浆进行分析,研究了其化学组分、结晶度、聚合度以及纤维形态对溶解浆在N-甲基吗啉-N-氧化物(NMMO)中溶解性的影响。结果表明:浆粕的溶解主要历经悬浮阶段、溶胀阶段和溶解阶段;溶胀阶段纤维发生非均匀溶胀的比例越高,溶解的时间越长;当浆粕质量符合制备Lyocell纤维的原料标准时,纤维表面的微量木质素对浆粕溶解起主要作用;木质素通过吸附作用沉积在纤维表面,与纤维素通过氢键结合减弱纤维溶胀,同时疏水性的木质素会阻碍NMMO向纤维内部渗透,增加溶解时间。

Analysis on factors influencing solution of Lyocell fiber spinning pulp

In order to explore the factors affecting the solubility of Lyocell fiber spinning pulp, four different dissolving pulps were analyzed to study the influence of their chemical composition, crystallinity, degree of polymerization and fiber morphology on the solubility of dissolving pulp in N-methylmorpholine-N-oxide (NMMO). The results showed that the dissolution of pulp experienced the suspension stage, swelling stage and dissolution stage. The higher the proportion of non-uniform swelling of fibers in the swelling stage, the longer the dissolution time. When the pulp quality meets the raw material standard for preparing Lyocell fiber, the trace lignin on the fiber surface plays a major role in dissolving the pulp. Lignin is deposited on the surface of the fiber through adsorption, and is combined with cellulose through hydrogen bonds to weaken fiber swelling. At the same time, hydrophobic lignin hindered the penetration of NMMO into the fiber and increased the dissolution time.