Synthetic method for cationic surface sizing agent

Abstract

The invention provides a synthetic method for a cationic surface sizing agent, which comprises the following steps: taking an organic solvent as a homogeneous reaction medium, taking styrene, acrylic ester and cationic monomer as comonomers, and adding a chain transfer agent and an initiator for polyreaction to prepare the cationic surface sizing agent with weight average molar mass between 1,000 and 2,000; and the weight percentage of the components is as follows: 60 to 75 percent of the organic solvent, 10 to 15 percent of the styrene, 10 to 15 percent of the acrylic ester, 2 to 10 percent of the cationic monomer, 0.1 to 1 percent of the chain transfer agent and 0.1 to 1 percent of the initiator. The synthetic method adopts a homogeneous non-emulsion polymerization process and a high-efficiency catalytic system, and has high conversion rate; and the prepared surface sizing agent can improve the ring crush strength of paper, improve a Cobb value, quicken mature speed without getting damp, reduce linting and dusting of the paper, obviously improve water resistance and strength of the paper, and improve application performances such as wear resistance, hydrophilicity of printing ink, ventilation property, stiffness and the like.

Description

technical field [0001] The invention belongs to the technical field of polymer compound synthesis, in particular to a method for synthesizing a cationic surface sizing agent, in particular to a method for synthesizing a cationic polystyrene-acrylate surface sizing agent. Background technique [0002] At present, in most domestic papermaking processes, the functions of waterproofing and moisture resistance depend on adding rosin or synthetic (such as AKD, ASA, etc.) sizing agents into the pulp. Rosin or synthetic sizing agents can give paper and A certain degree of sizing of cardboard, but there are many disadvantages: [0003] (1) Due to the large use of recycled pulp and the complex source of waste paper, the volatility of the pulp is increased, which also leads to the instability of sizing in the pulp, and the effect of sizing in the pulp is limited; [0004] (2) Adding in the pulp to increase the use of chemicals in the pulp system and affect the use effect of other chem...

AI Technical Summary

Problems solved by technology

[0003] (1) Since recycled pulp is used more and the source of waste paper is complicated, the volatility of pulp is increased, which also leads to the instability of pulp sizing, and the effect of pulp sizing is limited;

[0004] (2) Adding in slurry increases the use of chemicals in the slurry system and affects the use of other chemicals (such as retention and drainage aids, enhancers, etc.);

[0005] (3) The one-way retention rate of the sizing agent in the slurry is preferably less than 90%, and many rosin sizing agents are only about 60%. The lost sizing agent will form various resins and anionic garbage in the slurry system After a certain period of accumulation, it will affect the water filtration and forming of the next paper, affect the strength of the paper, and even stain the net and felt, thus affecting normal production

However, this method has too strict requirements on production process equipment, which does not meet the national conditions of our country, and is not conducive to widespread application.

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