Fundamentally, sodium carboxymethyl cellulose CMC and polyanionic cellulose PAC are the same product, and the raw materials for the production of sodium carboxymethyl cellulose and polyanionic cellulose are the same, but the production process is different, resulting in product Different metrics and parameters have different performance.
The earliest production of sodium carboxymethyl cellulose can only use the water-based method. The method of using water as the medium has low production cost, low product etherification degree and poor product quality, and can only produce low-grade products.
Later, the solvent method was successfully developed abroad to produce sodium carboxymethyl cellulose. This process is the same as the reaction process of the water-based method. It also consists of two stages of alkalization and etherification, but an organic solvent is used as the reaction medium, mainly alcohol. , this method can produce a new type of sodium carboxymethyl cellulose with high degree of substitution, high purity and high stability, and is named as polyanionic cellulose. The degree of substitution of this product is generally greater than 0.9, and this product is generally used in oil drilling. , can be used in complex environments,
Of course, the current product index substitution degree of sodium carboxymethyl cellulose also has products with substitution degree greater than 0.9, which are also used in many product industries, such as food industry, toothpaste, ceramics, textile printing and dyeing.
Therefore, polyanionic cellulose and sodium carboxymethyl cellulose are the same product, but it is just a convention. When used in the oil drilling industry, sodium carboxymethyl cellulose with a degree of substitution greater than 0.9 is called polyanionic cellulose.
