Method for preparing cation colophony/AKD neutral sizing agent

Abstract

The invention relates to a method for preparing a cation colophony / AKD neutral sizing agent. The method comprises the following steps: under the function of an organic solvent which can be mutually soluble to water, taking vinyl monomers, such as styrene, an acrylate class monomer, acrylamide and a derivative thereof, a cation monomer and the like, as a copolymerization monomer and preparing cation saponin-free benzene emulsion by saponin-free emulsion polymerization; taking the cation saponin-free benzene emulsion as a cation high molecular surfactant, emulsifying and dispersing colophony andlong-chain alkyl ketene multimer (AKD) and preparing cation colophony / AKD emulsion with favorable stability and sizing performance by homogenizing at high pressure. The invention does not use a smallmolecular emulsifying agent and cation starch in the preparation process of a product and overcomes the defects of easy bubbling, poor stability, poor sizing effect and the like of the traditional AKD emulsion. The cation colophony / AKD emulsion prepared by the invention has stronger cation performance, particles have positive charges and are beneficial to remaining and combining with paper fibre,and the cation high molecular surfactant also has a certain sizing synergistic action, thereby enhancing the stability and the sizing performance of the emulsion greatly.

Description

technical field

[0001] The invention belongs to the field of chemistry, in particular to a preparation method of cationic rosin / AKD neutral sizing agent. 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.

[0003] Alkyl ketene dimer (AKD) is a highly reactive medium-alkaline sizing agent, which has been widely used in domestic paper mills. The reactive functional group of AKD reacts with the hydroxyl group of the paper fiber to form a β-keto ester, which is bonded to the fiber frame, while the hydrophobic long-chain alkyl group turns to the paper surface to form a hydrophobic layer, making the paper waterproof and sizing Eff...