Anionic polyacrylamide as a paper dispersant
The paper industry is closely related to the development of national economy and social civilization. The consumption level of paper and board is one of the important symbols to measure the modernization and civilization of a country. At present, China is already a large producer and exporter of paper.
In the paper industry, the use of a lot of chemical additives, chemical additives mainly include retention aid China is the earliest invented paper country, according to research in the Western Han Dynasty there is a papermaking technology, but more backward, to the Eastern Han Dynasty, after Cai Lun's The improvement of papermaking technology has made great progress and development. With the development of the times, papermaking technology has also made great progress, to now have a variety of uses of paper. , Filter aid, dispersant, enhancer, defoamer, preservative, sizing agent. For paper dispersants, the most commonly used is the water-soluble polymer, in the paper dispersion on the anionic polyacrylamide (PAM) is the most ideal, polyacrylamide is a white particles or powder, easy to water, Insoluble in most organic solvents, because the molecules connected with hydroxyl, the negatively charged cellulose fiber adsorption, with the role of reducing the surface tension, is conducive to the water on the solid wet, Anionic polyacrylamide which is the fiber and filler dispersion in water It is advantageous that when the PAM solution is added to the slurry, the pulp and the filler surface form a bimolecular structure to improve the hydrophilicity of the solid particles such as fillers and fibers, and the various solid particles are far away from the electrostatic repulsion Maintain the maximum dynamic stability of the suspension, low molecular weight can improve the viscosity of the slurry, is conducive to the suspension of fiber, so PAM is a long fiber efficient dispersant. Anionic polyacrylamide High molecular weight polyacrylamide is a good flocculant, in the choice of paper dispersant must choose the appropriate PAM.