Application of Cellulose Ethers in Paper Industry
1. Paper Strengthening Agent
CMC, for example, can act as the dispersing agent of fibers and the paper strengthening agent, and can be added to the pulp. Since sodium carboxymethyl cellulose, the pulp and filler particles have the same charge, it helps to increase the evenness of the fiber. As the paper strengthening agent of internally added type, CMC can increase the bonding effects between the fibers, and improve such physical indicators as the tensile strength, the bursting strength and the evenness of the paper.
2.Wet-End Additives in Papermaking
CMC can act as the dispersing agent of fibers and the paper strengthening agent, and can be added to the pulp. Since sodium carboxymethyl cellulose, the pulp and filler particles have the same charge, it helps to increase the evenness of the fiber. As the paper strengthening agent of internally added type, CMC can increase the bonding effects between the fibers, and improve such physical indicators as the tensile strength, the bursting strength and the evenness of the paper. Sodium carboxymethyl cellulose can be used as the internal sizing agent for it has a certain degree of sizing itself, and can also be used as the protective agent of such sizing agents as rosin gum and AKD.
3.Surface Sizing Agent
Sodium carboxymethyl cellulose can be used as the surface sizing agent of paper to improve the surface strength of paper. Compared with the current use of polyvinyl alcohol and modified starch, the surface strength can increase by about 10%, while the amount can reduce by about 30%. Therefore, it is a very promising surface sizing agent of paper, and its series of new varieties should be actively developed. The cationic cellulose ether has superior surface sizing performance to the cationic starch, and not only can improve the surface strength of the paper, but also can improve the ink absorption properties of the paper as well as the dyeing effects. So it is also a very promising surface sizing agent.
Cellulose derivatives have many kinds and broad functions. Due to the superior performance, cellulose ethers has been widely used in the paper industry.