On the orientation of the chains in the mercerized cellulose

Abstract

The cold alkaline treatment or mercerization of cellulose is widely used in industry to enrich the cellulose raw with high-molecular-weight $$\alpha$$ α -cellulose. Washing out of hemicelluloses by alkalies is accompanied by the rearrangement of the cellulose chains’ packing, well known as a transition between cellulose I and cellulose II. Cellulose II can also be produced by the precipitation of the cellulose solutions (regeneration). The currently accepted theory implies that in cellulose II, both mercerized and regenerated, the macromolecules are arranged antiparallelly. However, forming such a structure in the course of the mercerization seems to be significantly hindered, while it seems to be quite possible in the regeneration process. In this work, we discuss the sticking points in the theory on the antiparallel structure of mercerized cellulose from a theoretical point of view summarizing all of the available experimental data in the field.

Comparative FT-IR Prospecting for Cellulose in Stems of Some Fiber Plants: Flax, Velvet Leaf, Hemp and Jute

“…The analysis of cellulose in the native state as it is found in textile plants before any significant structural modifications take place through processing, such as changes in the orientation of chains that occur following mercerization [65], can provide a characterization at the point "0" of the primary state in which cellulose is found in raw material. The identification of cellulose-specific regions in stems of given textile plants provides the basis and starting point for qualitative sorting and preliminary qualitative characterization.…”

Eco‐friendly production and performance evaluation of water‐resistant cellulose nanofiber bioaerogels

“…It is widely recognized that cellulose exhibits swelling and partial dissolution in sodium hydroxide aqueous solutions under low-temperature conditions. 56 In this study, the successful conversion of cellulose I to cellulose II can be attributed to the partial swelling of the CNF surface. As CNF possess a large surface area per unit volume, accessible OH groups are abundant on CNF surfaces, thus the surface undergoes swelling when the CNF are homogenized in NaOH solution and subsequently regenerated during freezing.…”

“…Mercerization involves treating cellulose I with a solution of sodium hydroxide, followed by regeneration (solubilization and recrystallization), which converts it into cellulose II, the most stable form of cellulose 55 . According to Zlenko and co‐workers, the conversion process changes the arrangement of cellulose fibers from parallel packing in native cellulose I to an generally accepted antiparallel arrangement in cellulose II 56 . The resulting cellulose, obtained through alkaline treatment or mercerization, is commonly known as regenerated cellulose.…”

“…55 According to Zlenko and co-workers, the conversion process changes the arrangement of cellulose fibers from parallel packing in native cellulose I to an generally accepted antiparallel arrangement in cellulose II. 56 The resulting cellulose, obtained through alkaline treatment or mercerization, is commonly known as regenerated cellulose. However, most existing methods utilize higher concentrations of NaOH (around 7%-8%) compared to the NaOH concentrations used in this study (0.1-0.5 M or equivalent to 0.4-2% NaOH).…”

Effect of mercerization on the properties and biodegradation behavior of LDPE and LDPE/PHB hybrid composites filled with castor bean cake

“…Mercerization is a process commonly used in the textile industry, which promotes the transformation of a typical crystal lattice, cellulose I, found in native cellulose into an allomorphic form of cellulose, called cellulose II [23][24][25][26][27]. In this process, a vegetable fiber interacts with a concentrated aqueous solution of a strong alkali base, resulting in a large swelling responsible for changes in the fiber's fine structure, morphology, dimensions and properties [24,[27][28][29].…”