Characterization of mercerized cellulose nanofibrils prepared by aqueous counter collision process

Abstract

Cellulose nanofibrils (CNFs) obtained by aqueous counter collision (ACC) methods have amphiphilic Janus-type properties, which appear markedly for ACC–CNFs prepared from bacterial nanocellulose (BNC) pellicles. The amphiphilic Janus-type surface is exposed because of the mechanism involved in ACC pulverizing of cellulose materials, in which the predominant interactions of the (2 0 0) lattice plane of the cellulose I crystal structure are weak interplanar van der Waals interactions. Such selective cleavage is more likely to occur for highly crystalline BNC. This study focused on alkali-mercerized cellulose samples, which are of lower crystallinity than BNC. The mercerized raw materials were subjected to ACC treatments and their fiber morphologies, crystallinities, and surface properties were compared to those of ACC–CNFs from native samples. In particular, the Wide-angle X-ray diffraction (WAXD) results suggested that the cleavage was most likely to occur at the (1 1 0) plane in nanofibrils derived from cellulose II, unlike (2 0 0) lattice plane for the case of cellulose I. Accordingly, the entire results indicate that the properties of the ACC-treated mercerized CNFs differ greatly from those of conventional ACC–CNFs composed of cellulose I crystalline structure. This is presumably because ACC nanopulverization proceeds depending on the surface structure and crystalline morphology of the raw material.

Targeting Bacterial Nanocellulose Properties through Tailored Downstream Techniques

“…On the other hand, when we conducted a screening of NaOH concentration (ranging from 0.2 to 1.0 M), a decreasing degradation curve was observed, which clearly indicates a weight variation after the drying process. This weight appears to be directly related to the NaOH concentration (Figure 1), suggesting a possible increment in cellulose chain compaction due to interactions with sodium cations [33,34], which could result in a decreased water content since the mercerized composite has a thinner interfacial matrix layer and fewer voids than the un-mercerized composite [35]. After submitting the membranes to either autoclaved or alkaline downstream processes, now at 0.1 M with in a different batch, comparing the weight means, the pooled standard deviation was 0.04, and all 95% confidence intervals (CI) overlapped with each other at least once, from the inferior range of 0.04-0.16 (KOH se) to 0.16-0.2859 (NaOH se).…”

“…On the other hand, when we conducted a screening of NaOH concentration (ranging from 0.2 to 1.0 M), a decreasing degradation curve was observed, which clearly indicates a weight variation after the drying process. This weight appears to be directly related to the NaOH concentration ( Figure 1 ), suggesting a possible increment in cellulose chain compaction due to interactions with sodium cations [ 33 , 34 ], which could result in a decreased water content since the mercerized composite has a thinner interfacial matrix layer and fewer voids than the un-mercerized composite [ 35 ].…”

Harnessing Nature’s Ingenuity: A Comprehensive Exploration of Nanocellulose from Production to Cutting-Edge Applications in Engineering and Sciences

“…However, as a precaution to prevent clogging at the nozzle section, the dimension of the cellulose slurry must be smaller than the diameter of the nozzle channels. ACC is yet another mechanical method elucidated for nanocellulose isolation, in which two high-pressure jets of aqueous suspensions containing cellulose are impacted by one another [90], as shown in Figure 11. Kose et al [91] isolated discrete CNFs via this method using a homogenized aqueous suspension containing a 0.4 weight percentage of bacterial cellulose.…”

Naturally Derived Janus Cellulose Nanomaterials: Anisotropic Cellulose Nanomaterial Building Blocks and Their Assembly into Asymmetric Structures

“…For example, BC and bamboo CNFs exhibited almost twice the hydrophobicity of wood pulp-derived CNFs . Interestingly, the cleavage for cellulose II occurred at the hydrophobic (110) plane, rather than the hydrophobic (200) plane in cellulose I . A detailed schematic cleavage diagram for amphiphilic Janus CNM structures is illustrated in Figure b.…”

“…139 Interestingly, the cleavage for cellulose II occurred at the hydrophobic (110) plane, rather than the hydrophobic (200) plane in cellulose I. 76 A detailed schematic cleavage diagram for amphiphilic Janus CNM structures is illustrated in Figure 3b. It was believed that the intersheet hydrogen bonding and van der Waals interactions were more easily cleaved than intrasheet hydrogen bonding during the aqueous counter collision.…”