Method for preparing amphoteric high molecular base AKD emulsion

Abstract

The invention discloses a method for preparing amphoteric high molecular base AKD emulsion. The method comprises the following steps: under the function of a cosolvent and a molecular weight regulator, taking vinyl monomers, such as styrene, acrylate, acrylamide, a cation monomer, (methyl) acrylic acid and the like, as a copolymerization monomer and preparing amphoteric saponin-free benzene emulsion by a saponin-free emulsion polymerization method; taking the amphoteric saponin-free benzene emulsion as an amphoteric high molecular surfactant, emulsifying and dispersing a long-chain alkyl ketene multimer (AKD) with excellent hydrophobic property and preparing the AKD emulsion with favorable stability and sizing performance by shearing and dispersing. The invention does not use a small molecular emulsifying agent and cation starch in the preparation process and overcomes the defects of easy bubbling, poor stability, poor sizing effect and the like of the traditional AKD emulsion; the prepared amphoteric high molecular base AKD emulsion has anionic properties and cationic properties and is free from the interference of the anionic impurities of a papermaking wet part system, and the retention rate is greatly enhanced.

Description

technical field

[0001] The invention belongs to the field of macromolecular chemistry, and in particular relates to a preparation method of an amphoteric macromolecule-based AKD emulsion. Background technique

[0002] With the modernization of offset printing technology, the quality requirements for paper are increasing, and the demand for medium-alkaline paper is also gradually increasing. Compared with acid sizing, neutral sizing has more obvious advantages in terms of improving paper whiteness, improving printing adaptability, reducing overall cost, and favoring the market and users. Practice has proved that AKD has become the most mature and effective neutral sizing agent used by domestic paper mills. Due to the characteristics of AKD's high activity and easy hydrolysis, the formulation of its emulsion should not only solve the problem of emulsification, but also solve the problem of its stability. Traditional AKD emulsions basically use cationic starch and some small ...