What's the viscosity of sodium carboxymethyl cellulose?
What's the viscosity of sodium carboxymethyl cellulose?
The viscosity of sodium carboxymethyl cellulose (CMC) is directly related to its application effectiveness in many fields, depending on a variety of parameters.
Viscosity-affecting factors
1.Molecular weight.
The molecular weight of CMC is one of the most important elements regulating its viscosity, and the higher the molecular weight, the more viscous. The reason for this is that a higher molecular weight results in longer molecule chains, which increase intermolecular interactions and entanglement, increasing the solution's viscosity.
2.Degree of substitution.
At low degrees of substitution, appropriately increasing the degree of substitution can disrupt the molecular crystal structure, making the molecular chains easier to dissolve and stretch, thereby enhancing the solution viscosity. However, a high degree of substitution can significantly weaken the intermolecular forces, leading to reduced chain entanglements and potentially decreased viscosity.
3.Solution concentration.
The viscosity of CMC solution increases significantly with increasing concentration; however, at extremely high concentrations, due to repulsive interactions between molecular chains or steric hindrance effects, the viscosity may no longer continue to rise.
4.Temperature
Generally speaking, an increase in temperature leads to a decrease in the viscosity of CMC solutions, as the thermal motion of molecules intensifies and intermolecular interactions weaken.
The impact of different viscosities of CMC on application effectiveness
Low-viscosity CMC provides a slight thickening effect on one hand, such as in certain beverages and low-fat foods, avoiding excessive thickening that affects the taste. On the other hand, its suspension stability is relatively weak, making it more suitable for systems with smaller particles or lower dispersion requirements, suchas simple water-based coatings.
Medium-viscosity CMC can impart appropriate viscosity and texture to products, thus finding widespread applications in areas such as sauces, ice cream, and cosmetics (e.g., emulsions).
High-viscosity CMC has a significant thickening effect, suitable for applications requiring high viscosity and stability, such as high-performance coatings and drilling fluids, ensuring greater construction performance and final quality.