Storage and Transportation Problems of CMC and Its Degree of Substitution

Storage and Transportation Problems of CMC and Its Degree of Substitution

Ⅰ. Storage and transportation problems of carboxymethyl cellulose CMC


If the storage and transportation of CMC is not appropriate, it will inevitably have some impact on the later use. Therefore, you must master the relevant knowledge of storage and transportation when using it. The following is a brief introduction for your reference.


1. According to its molecular weight or degree of substitution, CMC can be a fully soluble or insoluble polymer. It is precisely because of its outstanding solubility that it is strictly forbidden to contact with water during storage, otherwise it will gel or partially dissolve resulting in unusable.


2. It is rain-proof during transportation, and iron hooks are strictly prohibited for loading and unloading. The long-term storage of carboxymethyl cellulose cmc and the stacking pressure may cause agglomeration when unpacking, which will cause inconvenience but will not affect the quality.


3. There is also the basic principle of transporting chemicals. The storage of this product requires that it be stored in a ventilated and dry place.


The storage and transportation of CMC has a lot to do with its properties, such as this highly soluble item, other precautions are the general principles of storage and transportation, so everyone must prevent CMC from coming into contact with water.


Ⅱ. Knowledge of carboxymethyl cellulose cmc substitution degree and other indicators


The degree of substitution is a performance index of cmc, and it is also a factor to detect its quality. In addition, there are also the degree of polymerization and viscosity, which are also some related typical indicators. For relevant knowledge points, please refer to the following content.


1. Degree of substitution and solubility: Degree of substitution refers to the average number of sodium carboxymethyl groups attached to each cellulose unit. Anhydroglucose on the cellulose molecule has three alcohol groups: one primary alcohol, two secondary alcohols, All three alcohol groups can react with sodium chloroacetate.


The primary alcohol group has high reactivity, so the substituent will first replace this group to make the reactant molecule longer, and the maximum value of the degree of substitution is 3, but the most widely used in industry is that the degree of substitution varies between 0.5 and 1.2. Carboxymethylcellulose.


There is a big difference in the characteristics of CMC with a degree of substitution of 0.55-0.65 and CMC with a degree of substitution of 0.85-0.95. The former only has poor temperature resistance and poor salt resistance, but the latter has good temperature resistance. And salt resistance is superior.


2. Degree of polymerization and viscosity: The degree of polymerization refers to the length of the cellulose chain that determines the viscosity. The longer the cellulose chain is, the greater the viscosity. The same is true for CMC solutions. The molecules have a linear structure, so they can form high-viscosity solutions. The viscosity reflects the interaction force between molecules.


3. Viscosity: Change the concentration of the carboxymethyl cellulose aqueous solution to obtain a solution with a highly variable viscosity. When it comes to viscosity, there are three factors that must be considered: the concentration of the solution; the temperature during measurement; the type of viscometer used.


The quality of CMC can be judged by indicators such as degree of substitution, degree of polymerization, viscosity, etc., so if you want to buy high-quality products, you must first understand its related knowledge points.