Cellulose in solution can be assembled into textile fibers by wet-spinning (Viscose etc.) or dry-jet wet spinning (Lyocell, Ioncell etc.), which leads to significant differences in the mechanical properties of fibers. We use scanning X-ray microdiffraction (SXM) to reveal regenerated fibers having a “skin-core” morphology. The “core” region comprises microfibrils (MFs) with ~100 nm in diameter. The cellulose forms elementary fibrils having a ribbon-like cross sectional shape of about 6 × 2 nm, which are packed into MFs. Our SXM studies demonstrate that MFs within Ioncell fibers are composed of elementary fibrils with homogeneous morphologies. Furthermore, the stacking of cellulose molecular sheets within elementary fibrils of Viscose fibers is preferentially along the 010 direction, while those of Ioncell fibers preferably stack in the 1–10 direction. The better structural regularities and distinct morphologies of elementary fibrils give Ioncell fibers enhanced mechanical properties and a wet strength far superior to those of Viscose fibers.

溶液中的纤维素可以通过湿法纺丝（粘胶等）或干喷湿法纺丝（Lyocell、Ioncell等）组装成纺织纤维，这导致纤维的机械性能存在显着差异。我们使用扫描 X 射线微衍射 (SXM) 来揭示具有“皮芯”形态的再生纤维。“核心”区域由直径约 100 nm 的微纤维 (MF) 组成。纤维素形成具有约6×2nm的带状横截面形状的基本原纤维，其被填充到MF中。我们的 SXM 研究表明，Ioncell 纤维内的 MF 由具有均匀形态的基本原纤维组成。此外，粘胶纤维的基本原纤维内的纤维素分子片优先沿010方向堆叠，而Ioncell纤维的纤维素分子片优选沿1-10方向堆叠。基本原纤维更好的结构规律性和独特的形态赋予 Ioncell 纤维增强的机械性能和远远优于粘胶纤维的湿强度。