Fibre Particle Engineering, University of Oulu, Oulu, Finland.
Fibre Particle Engineering, University of Oulu, Oulu, Finland; Division of Materials Science, Luleå University of Technology, Luleå, Sweden.
Carbohydr Polym. 2018 Oct 1;197:92-99. doi: 10.1016/j.carbpol.2018.05.072. Epub 2018 May 26.
This paper addresses the issue of high water retention by cellulose nanofibers (CNFs) that lead to exorbitant time consumption in the dewatering of CNF suspensions. This has been a bottleneck, which is restricting the commercialization of CNF derived products such as nanopapers and CNF reinforced paper sheets. As a remedy, we suggest an eco-friendly water-based approach that involves the use of sonication energy and lactic acid (LA) to modify the surface of CNFs. The suggested modification resulted in rapid water drainage, and dewatering was completed in 10 min; with unmodified CNFs, it took around 45 min. We have also compared the draining characteristics of LA modification of CNF suspensions with a common draining agent (NaCl); LA modification drains water 56% faster than the use of NaCl, and produced mechanically superior dimensionally stable nanopaper. Additionally, LA modification allows the addition of 10 wt.% CNF in paper sheets, with dewatering done in 2 min (while the unmodified CNFs took 23 min).
本文针对纤维素纳米纤维（CNF）保水率高的问题，导致 CNF 悬浮液脱水时间过长。这一直是一个瓶颈，限制了 CNF 衍生产品（如纳米纸和 CNF 增强纸）的商业化。作为一种补救措施，我们建议采用一种环保的水基方法，利用超声能量和乳酸（LA）来修饰 CNF 的表面。所提出的修饰方法导致快速排水，脱水在 10 分钟内完成；而未修饰的 CNF 则需要大约 45 分钟。我们还比较了 CNF 悬浮液中 LA 修饰与常用脱水剂（NaCl）的排水特性；LA 修饰比使用 NaCl 排水快 56%，并生产出机械性能更优的尺寸稳定的纳米纸。此外，LA 修饰允许在纸页中添加 10wt.%的 CNF，脱水时间为 2 分钟（而未修饰的 CNF 需要 23 分钟）。
