Method for preparing heavy calcium carbonate dispersing agent for papermaking

Abstract

The invention discloses a method for preparing a heavy calcium carbonate dispersing agent for papermaking. The method comprises the following steps: (1) mixing water, maleic anhydride, itaconic acid and ethylene diamine tetraacetic acid disodium salt, adding an initiating system reducing agent, preparing a solution A, stirring at a speed of 200 revolutions per minute, heating at the temperature of 85 DEG C, and introducing N2; (2) mixing methacrylic acid, hydroxyethyl methylacrylat and water, and preparing a dropping solution B; (3) preparing 2-acrylamide-2-methallyl sulfonate, an initiating system oxidizing agent and water into a dropping solution C; (4) preparing water and the initiating system oxidizing agent into a 10% solution D; (5) simultaneously dripping the dropping solution B and the dropping solution C into the solution A, completing dropping within an hour, maintaining the temperature and reacting for an hour; finally, dripping the solution D, completing dropping within half an hour, maintaining the temperature and reacting for 2.5 hours; (6) cooling to the temperature of 50 DEG C, regulating the pH value to 7.0 by using a 40% NaOH solution, obtaining a quadripolymer, and compounding the quadripolymer with sodium stearate according to a mass ratio of 5:1, thereby obtaining the heavy calcium carbonate dispersing agent for papermaking.

Description

technical field [0001] The invention relates to a preparation method of a heavy calcium carbonate dispersant, in particular to a preparation method of a heavy calcium carbonate dispersant for papermaking. Background technique [0002] At present, the paper industry mainly uses heavy calcium carbonate and slurry calcium prepared by water as the coating for paper coating. Calcium carbonate is prone to "agglomeration" due to its huge surface and surface effect, so adding a dispersant to the slurry calcium solution is the most effective way to keep the particle dispersion stable. The adsorption of inorganic dispersants on the surface of particles is not firm, which easily leads to re-flocculation of particles, while polymer dispersants rely on their own steric hindrance and electrostatic repulsion to stabilize the particle dispersion, which can effectively make up for the shortcomings of traditional dispersants. [0003] In the past, homopolymers of acrylic acid (AA) were used ...

AI Technical Summary

Problems solved by technology

Homopolymer is not a good dispersant, because it is a better solvation chain or a better anchoring group, so the amount used to achieve the same dispersion effect is larger, and the cost is higher