This study aimed at developing a clean, low-cost and promising way to manufacture the lignin-coated cellulose nanofibrils (L-CNFs) from switchgrass by combining hydrothermal pretreatment with mechanical fibrillation by a disk grinder. The effects of hydrothermal pretreatment at different reaction temperatures and time durations on the chemical constituents, thermal stability, micro-morphology, nano-mechanical property of switchgrass cell wall as well as the energy consumption during the mechanical fibrillation process were comprehensively investigated. The results indicate that the reaction temperature was a more crucial factor influencing the removal of hemicellulose during hydrothermal pretreatment than the time duration. A higher temperature improved the thermal stability of switchgrass but was detrimental to the elastic modulus and the hardness of its cell walls with the shape varying from roundish to multangular. Compared to the control samples, the elastic modulus and the hardness for samples at 160 °C pretreatment for 60 min sharply decreased by 52.2 % and 36.0 %, respectively. The semi-rigid cell wall of switchgrass pretreated at 180 °C for 30 min, consisting of low hemicellulose content (2.96 %) and moderate lignin content (26.4 %), effectively facilitated the mechanical fibrillation of switchgrass with low energy consumption (8.31 kW h/kg) and obtained the high-performance L-CNFs with the small diameter (8.4 nm).

这项研究旨在开发一种清洁，低成本和有前途的方法，通过将水热预处理与圆盘磨床的机械原纤化相结合，从柳枝manufacture制造木质素包覆的纤维素纳米原纤维（L-CNF）。全面研究了在不同反应温度和持续时间下水热预处理对柳枝cell细胞壁化学成分，热稳定性，微观形貌，纳米力学性能以及机械原纤化过程中能耗的影响。结果表明，反应时间比时间长短是影响水热预处理过程中半纤维素去除的关键因素。较高的温度改善了柳枝the的热稳定性，但不利于其弹性模量和其细胞壁的硬度，其形状从圆形变为多角形。与对照样品相比，在160°C预处理60分钟的样品的弹性模量和硬度分别急剧下降了52.2％和36.0％。柳枝switch的半刚性细胞壁在180°C预处理30分钟，由低半纤维素含量（2.96％）和中等木质素含量（26.4％）组成，有效促进了柳枝energy的机械原纤化，能耗低（8.31 kW h） / kg），并获得了小直径（8.4 nm）的高性能L-CNF。160℃预处理60分钟的样品的弹性模量和硬度分别急剧下降52.2％和36.0％。柳枝switch的半刚性细胞壁在180°C预处理30分钟，由低半纤维素含量（2.96％）和中等木质素含量（26.4％）组成，有效促进了柳枝switch的机械原纤化，能耗低（8.31 kW h） / kg），并获得了小直径（8.4 nm）的高性能L-CNF。160℃预处理60分钟的样品的弹性模量和硬度分别急剧下降52.2％和36.0％。柳枝switch的半刚性细胞壁在180°C预处理30分钟，由低半纤维素含量（2.96％）和中等木质素含量（26.4％）组成，有效促进了柳枝energy的机械原纤化，能耗低（8.31 kW h） / kg），并获得了小直径（8.4 nm）的高性能L-CNF。