Molecular Architecture
Molecular hydration layers form around dissolved polysaccharide chains when cellulose is treated with highly concentrated sodium hydroxide solutions. These stable glucan solvation shells shield the polymer backbone from chemical attack and prevent the rapid precipitation of dissolved cellulose. This structural arrangement determines how well the cotton fibers swell during finishing operations.
Solubility Boundary
The protective layer of water and sodium ions restricts the interaction of individual carbohydrate chains with neighboring molecules. While glucan solvation shells remain intact, the dissolved cellulose remains dispersed within the highly alkaline mercerizing bath. If the sodium hydroxide concentration falls, the shells disintegrate, leading to rapid aggregation and clogging of the process equipment.
Swelling Dynamic
Highly aligned hydrogen bonds coordinate multiple water molecules around each glucose unit of the dissolved polymer. The stability of these glucan solvation shells directly influences the viscosity of the recycling streams. When the ionic strength of the bath changes, the outer layers of the shell reorganize, which can alter the flow characteristics of the solution.
This reorganization is highly dependent on both salt concentrations and shear forces.
Thermal Response
Cooler temperatures favor the formation of these protective structures by stabilizing the hydrogen-bonded networks. At higher temperatures, glucan solvation shells break down, which promotes the separation of organic contaminants from the lye.
