Abstract This work reports a study on the effects of different types and aspect ratios of cellulose nanocrystals (CNCs) on properties of poly (vinyl alcohol) (PVA) composite fibers. CNCs were extracted from wood pulp and cotton and reinforced into PVA to produce fibers by dry-jet-wet spinning. The fibers were collected as-spun and with the first stage drawing up to draw ratio 2. The elastic modulus and tensile strength of the fibers improved with increasing CNC content (5–15 wt. %) at the expense of their strain-to-failure. It was also observed that the mechanical properties of fibers reinforced with cotton CNC were higher than the fibers with wood CNC at the same amount of CNCs due to their higher aspect ratio. The degree of orientation along the spun fiber axis was quantified by 2D X-ray diffraction. As expected, the CNC orientation correlates to the mechanical properties of the fibers. Micromechanical models were used to predict the fiber performance and compare with experimental results. Finally, surface and cross-sectional morphologies of fibers were analyzed by scanning electron microscopy and optical microscopy.

中文翻译：

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纤维素纳米晶的纵横比和晶体取向对聚乙烯醇复合纤维性能的影响

摘要 这项工作报告了不同类型和长宽比的纤维素纳米晶体 (CNC) 对聚乙烯醇 (PVA) 复合纤维性能影响的研究。CNCs 从木浆和棉花中提取并增强为 PVA 以通过干喷湿法纺丝生产纤维。纤维在初纺时收集，并在第一阶段拉伸至拉伸比 2。纤维的弹性模量和拉伸强度随着 CNC 含量（5-15 重量％）的增加而提高，但其应变至失败。还观察到，在相同数量的 CNCs 下，棉 CNC 增强纤维的机械性能高于木 CNC 纤维，因为它们具有更高的纵横比。沿纺成纤维轴的取向度通过二维 X 射线衍射进行量化。正如预期的那样，CNC 取向与纤维的机械性能相关。微机械模型用于预测纤维性能并与实验结果进行比较。最后，通过扫描电子显微镜和光学显微镜分析了纤维的表面和横截面形态。