In this research, cellulose nanofiber (CNF) was isolated by the combination of chemical 2,2,6,6-tetramethylpiperidine-1-oxylradical (TEMPO)-oxidation and physical aqueous counter collision (ACC) methods The combination of TEMPO-oxidation and ACC is an efficient method to isolate CNFs by reducing chemical usage in TEMPO-oxidation and saving energy in ACC along with controlling the size of CNFs. Two cellulose sources, hardwood bleached kraft pulp (HW) and softwood bleached kraft pulp (SW), were used for the CNF isolation with different TEMPO oxidation time and a defined number of ACC pass. The CNF properties were investigated and compared in term of morphology, crystallinity index, transparency and birefringence. The width of the isolated CNFs from HW is in the range of 15.1 nm–17.5 nm, and that of the SW CNFs is between 18.4 nm and 22 nm depending on the TEMPO oxidation time. This difference is due to the fact that SW is less oxidized than HW under the same chemical dosage, which results in larger width of SW-CNFs than HW-CNFs. The HW-CNF treated with TEMPO for over 2 hours and isolated using ACC with 5 pass offers almost 90% transparency. Birefringence of CNFs exhibits that HW-CNFs show better birefringence phenomenon than SW-CNFs. The combination of TEMPO-oxidation and ACC methods is useful for isolating CNFs with its size control.

在这项研究中，通过化学2,2,6,6-四甲基哌啶-1-氧基自由基（TEMPO）-氧化和物理水反碰撞（ACC）方法的组合分离了纤维素纳米纤维（CNF）。 ACC是通过减少TEMPO氧化过程中的化学用量并节省ACC中的能量以及控制CNF大小的有效方法来分离CNF。CNF分离使用了两种纤维素来源，即硬木漂白牛皮纸浆（HW）和软木漂白牛皮纸浆（SW），具有不同的TEMPO氧化时间和一定数量的ACC通过。研究了CNF的性质，并在形态，结晶度，透明度和双折射方面进行了比较。与硬件隔离的CNF的宽度在15.1 nm-17.5 nm的范围内，而SW CNF的宽度在18之间。4纳米和22纳米，具体取决于TEMPO氧化时间。这种差异是由于在相同化学剂量下SW的氧化程度低于HW，导致SW-CNF的宽度大于HW-CNF的宽度。用TEMPO处理2小时以上的HW-CNF，并使用ACC进行5次通过分离，可提供近90％的透明度。CNF的双折射表明，HW-CNF显示出比SW-CNF更好的双折射现象。TEMPO-氧化和ACC方法的结合可用于通过尺寸控制分离CNF。CNF的双折射表明，HW-CNF显示出比SW-CNF更好的双折射现象。TEMPO-氧化和ACC方法的结合可用于通过尺寸控制分离CNF。CNF的双折射表明，HW-CNF显示出比SW-CNF更好的双折射现象。TEMPO-氧化和ACC方法的结合可用于通过尺寸控制分离CNF。