Abstract

A comprehensive crystallographic investigation was performed by using X-ray (from cobalt source) diffraction (XRD) technique on different bamboo species, natural bamboo fibers (NBFs), commercial bamboo viscose products, and different conventional fibers. Crystallinity indexes (CIs) were estimated as 61–67% of bamboo plants, 69–73% of NBFs, 35–40% of bamboo viscose, and 77–80% of cotton fibers in this study. Results suggest that CI gradually increased during the delignification process to create NBFs up to a certain point and then decreased with further processes. Knowing this behavior informs decisions of the appropriate chemicals or enzymes for further modification processes and continuing to maintain the expected strength of the fiber. Therefore, delignifying raw bamboo increased the strength of the fibers until the maximum CI was achieved, but further extraction of lignin reduced the strength of the NBF resulting in a higher number of fiber breakage and short fibers. Red Margin was found to have lower CI that hinted at easier NBF extraction. With overall crystallite size of 35–39 Å, four crystalline peaks were detected in all bamboo and NBF specimens as (101), $\left(10\overline{1}\right),$ $\left(002\right),$ and $(040)$ at 17.0–18.6°, 18.5–19.4°, ∼25.5°, and ∼40.5°, respectively. Moreover, this study provides a list of lattice planes, interplanar spacings, reflection angles, and crystallite dimensions of the four targeted bamboo and NBF materials.

摘要

使用 X 射线（来自钴源）衍射 (XRD) 技术对不同的竹种、天然竹纤维 (NBF)、商业竹粘胶产品和不同的常规纤维进行了全面的晶体学研究。在本研究中，结晶度指数 (CI) 估计为 61-67% 的竹植物、69-73% 的 NBF、35-40% 的竹粘胶和 77-80% 的棉纤维。结果表明，CI 在脱木素过程中逐渐增加以产生 NBF，直至达到某个点，然后随着进一步的过程而降低。了解这种行为有助于决定适当的化学品或酶以进行进一步的改性过程并继续保持纤维的预期强度。因此，对原竹进行脱木素会增加纤维的强度，直到达到最大 CI，但进一步提取木质素会降低 NBF 的强度，导致更多的纤维断裂和短纤维。发现 Red Margin 具有较低的 CI，暗示更容易提取 NBF。整体微晶尺寸为 35-39 Å，在所有竹子和 NBF 样品中检测到四个结晶峰，如（101），$\left(10\overline{1}\right),$ $\left(002\right),$ 和 $(040)$分别在 17.0-18.6°、18.5-19.4°、~25.5° 和~40.5°。此外，本研究提供了四种目标竹子和 NBF 材料的晶格平面、晶面间距、反射角和微晶尺寸列表。