Product Introduction
Chemical structure
Cellogen features:
1 Soluble in cold or warm water to make a viscous solution.
2 Stored for a long period of time, there is little change in viscosity.
3. Excellent emulsification dispersion and solid dispersion performance.
4. It can form a tough and transparent film and has a bonding effect.
5 Compared with natural gums, it is not easy to spoil.
6. Insoluble in oil, lubricating grease and organic solvents.
7. Physiologically non-toxic.
8 Stable quality, uniform ratio and high purity.
9. There are many varieties, low viscosity to high viscosity, low etherification to high etherification.
Cellogen standard trait
Appearance: White powder.
Purity: more than 99% (dry product).
Moisture: 10% or less.
Salt fraction: less than 1%.
Browning temperature: about 225°C
Blackening temperature: about 250°C
pH: 65-8.5 (1% aqueous solution).
Reference weight: about 035-0.70g/ml
Pre-existing chemical substances No：「8」-203
cas no.：9004-32-4
Cellogen R&D and results presentation
In 1949, the CMC was developed, and full-scale production began in 1950. In 1960, production began at the Oigata Plant in Niigata Prefecture, Japan, and its production capacity is the largest in Japan and has a certain influence in the world.
The status of ISO acquisition at the Oqata Plant is as follows.
1998: ISO9002
2003: ISO9001 (2000 version).
2002: ISO14001
CMC-Cellogen series
The CMC models that have achieved results in battery are as follows (Viscosity, substitution, and molecular weight data can be consulted on a case-by-case basis
recruitment
CMC Overview
CMC is an important cellulose ether, which is a water-soluble polyanionic cellulose compound obtained by chemical modification of natural fibers, which is easily soluble in cold and hot water. It has unusual and extremely valuable comprehensive physical and chemical properties such as emulsifying dispersant, solid dispersion, non-corrosive, physiologically harmless, etc., and is a natural polymer derivative with a wide range of uses. CMC is a white or yellowish powder, granular or fibrous solid, odorless, tasteless and non-toxic.
CMC has excellent properties such as thickening, dispersion, suspension, bonding, film formation, colloidal protection and moisture protection, and is widely used in food, medicine, toothpaste and other industries. CMC is a macromolecular chemical that absorbs water and expands, and when swollen in water, it can form a clear, viscous glue that is neutral in terms of pH. Solid CMC is stable to light and room temperature, and can be stored for a long time in a dry environment.
CMC's superior properties such as thickening, water retention, metabolic inertness, film-forming formability, dispersion stability, etc., can be used as thickener, water retention agent, adhesive, lubricant, emulsifier, co-suspension agent, tablet matrix, biological matrix and biological product carrier.
CMC Other Properties
Solubility
Carboxymethyl cellulose easily absorbs water, has good water solubility, and dissolves in cold or hot water to become a colloidal solution. Insoluble in organic solvents such as methanol, ethanol, propylene copper, chloroform and benzene. The degree of substitution is an important factor affecting its water solubility, and viscosity also has a great influence on water solubility. Usually the viscosity is 25 MPas-50000mpa.s, the degree of substitution is 03. It is alkali-soluble. The degree of substitution is greater than 04 is water-soluble. As the degree of substitution increases, so does the transparency of the solution. The dissolution of CMC is the same as that of other polymer dielectrics, and when it is dissolved, it first swells and then gradually dissolves. Therefore, when preparing the solution, each particle should be evenly wetted in order to dissolve quickly. Otherwise, after it expands in the aqueous solution, the particles adhere to each other to form a strong film or micelle, which makes the particles not easy to disperse and causes difficulty in dissolving.
Factors influencing the viscosity of a solution
Effect of solution concentration:
Regardless of the high, medium and low viscosity of CMC, its viscosity increases with the increase of solution concentration, and the logarithmic value of solution concentration and viscosity is approximately linear relationship.
Effect of pH:
The viscosity of the 1% CMC solution is at pH 65-9.Maximum and most stable at 0. Generally speaking, the pH value is 90-11.The viscosity does not change much in the range of 0. But at pH 6, the viscosity decreases rapidly and begins to form CMC acids, which are at pH 2It is completed at 5 o'clock;If the pH is 9, the viscosity will also decrease, at first slowly, but when the pH is 11At 5 o'clock, a sharp decline began. This is because the unsubstituted hydroxyl group binds to the base molecule, facilitating the result of cellulose dispersion.
Effect of temperature:
The viscosity of the CMC solution decreases with increasing temperature. When cooled, the viscosity recovers, but when the temperature rises to a certain level, a permanent decrease in viscosity occurs. However, it should be pointed out that the reduction of viscosity is closely related to the degree of CMC substitution, and the higher the degree of substitution, the less the viscosity is affected by temperature.
Effects of salts:
The presence of various inorganic salt plasmas reduces the viscosity of the CMC solution, and the effect of salts on the viscosity depends almost on the valence of the cation. Generally, it is water-soluble when it encounters monovalent cationic salts, insoluble salts when it encounters trivalent cationic salts, and between monovalent and trivalent cationic salts when it encounters divalent cationic salts.
Shear rate Effect of flow velocity gradient:
Because the CMC solution is not a Newtonian fluid, it is a pseudoplastic fluid. Its flow properties cannot be described by a simple Newtonian formula, but the apparent viscosity of the solution is still a function of the flow velocity gradient at the time of determination.
Processability
Water retention: water-based slurry, it goes without saying, experienced colleagues should understand the importance of water retention, water loss leads to the change of solid content and causes the areal density to deteriorate, which is a very bad result.
Suspension Stability:
Needless to say, this is the core of the slurry dispersion and stability, simply put, the CMC fiber covers the entire slurry space, blocking the graphite particles. Obviously, if CMC is not added, the slurry will settle like silt;In addition, CMC-Na, as a polyanionic cellulose compound, can form an electric double-layer electrostatic stabilization with powder.
Good flow properties and leveling properties of coating processing
During the coating process, the coating is subjected to a wide range of different shear conditions, and it is essential to adjust the correct rheological properties to maintain the good running properties of the coating. This becomes even more important as the coating speed increases.
CMC plays a thickening role in the battery, increasing viscosity, improving the leveling of the material when coating, and also playing a dispersive role to prevent the material from stratification and sedimentation during batching, and improve the dispersion effect.
The difference in the molecular weight of the material and the difference in the degree of displacement lead to the difference in the amount used in the batching.