Department of Sustainable Bioproducts, Mississippi State University, Box 9820, Mississippi State, MS 39762, USA.
Department of Sustainable Bioproducts, Mississippi State University, Box 9820, Mississippi State, MS 39762, USA.
Carbohydr Polym. 2015 Dec 10;134:581-9. doi: 10.1016/j.carbpol.2015.08.031. Epub 2015 Aug 18.
Recently, cellulose nanofibers (CNFs) have received wide attention in green nanomaterial technologies. Production of CNFs from agricultural residues has many economic and environmental advantages. In this study, four different CNFs were prepared from cotton stalks by different chemical treatments followed by ultrasonication. CNFs were prepared from untreated bleached pulp, sulfuric acid hydrolysis, and TEMPO [(2,2,6,6-tetramethylpiperidin-1-yl) oxy radical]-mediated oxidation process. Physical and chemical properties of the prepared CNFs such as morphological (FE-SEM, AFM), structural (FTIR), and thermal gravimetric analysis (TGA) were investigated. Characterization results clearly showed that the method of preparation results in a significant difference in the structure, thermal stability, shape and dimensions of the produced CNFs. TEMPO-mediated oxidation produced brighter and higher yields (>90%) of CNFs compared to other methods. FE-SEM and AFM analysis clearly indicated that, TEMPO-mediated oxidation produced uniform nano-sized fibers with a very small diameter (3-15 nm width) and very small length (10-100 nm). This was the first time uniform and very small nanofibers were produced.
最近，纤维素纳米纤维（CNFs）在绿色纳米材料技术中受到了广泛关注。用农业废弃物生产 CNFs 具有许多经济和环境优势。在这项研究中，通过不同的化学处理方法，然后进行超声处理，从棉秆中制备了四种不同的 CNFs。CNFs 是由未经处理的漂白浆、硫酸水解和 TEMPO [（2,2,6,6-四甲基哌啶-1-基）氧基自由基]介导的氧化过程制备的。研究了所制备的 CNFs 的物理和化学性质，如形态（FE-SEM、AFM）、结构（FTIR）和热重分析（TGA）。表征结果清楚地表明，制备方法导致所制备的 CNFs 的结构、热稳定性、形状和尺寸有显著差异。与其他方法相比，TEMPO 介导的氧化产生了更亮、更高产率（>90%）的 CNFs。FE-SEM 和 AFM 分析清楚地表明，TEMPO 介导的氧化产生了均匀的纳米尺寸纤维，其直径非常小（3-15nm 宽），长度非常小（10-100nm）。这是第一次生产出均匀且非常小的纳米纤维。
