Preparation method of crosslinked grafted modified polyvinyl alcohol surface reinforcing agent

Abstract

The invention relates to a preparation method of a crosslinked grafted modified polyvinyl alcohol surface reinforcing agent. The method comprises the steps of: evenly mixing polyvinyl alcohol with water to obtain a polyvinyl alcohol water solution; increasing the temperature of the water solution, adding ketone carboxyl-containing vinyl monomer, cationic monomer, long side chain radical-containing vinyl monomer, self-crosslinking monomer, and other types of vinyl monomers, to obtain a vinyl monomer/ polyvinyl alcohol mixture solution; evenly mixing water with a water-soluble initiator to obtain an initiator water solution; dropwise adding the initiator water solution into the mixture solution, increasing the temperature of the system, reacting until no acrylic ester monomer smell exists; cooling the temperature of the system to room temperature, regulating the pH value with alkali, adding hydrazine or the derivatives thereof to be stirred evenly, thus obtaining the crosslinked grafted modified polyvinyl alcohol surface reinforcing agent. The stability of the system cannot be influenced by adopting the preparation method; the crosslinked grafted modified polyvinyl alcohol surface reinforcing agent is used for paper surface reinforcing agent, the surface strength, water resistance, tensile strength, folding strength and the like of paper can be greatly improved, and the film forming property can be enhanced.

Description

technical field [0001] The invention relates to a preparation method of a crosslinking graft modified polyvinyl alcohol surface enhancer. Background technique [0002] Polyvinyl alcohol has excellent bonding strength and film-forming properties, and has been used for surface sizing of paper for a long time, which can improve the tensile strength and folding endurance of paper to a certain extent. However, there are still some deficiencies in the use of polyvinyl alcohol for surface sizing. Although the surface of polyvinyl alcohol contains a large number of hydroxyl groups, it cannot completely form hydrogen bonds with the fibers. In addition, it is easy to absorb water and become damp in humid air. The water resistance and surface strength of the paper are poor, and it is prone to lint and powder loss during the printing process. Phenomenon. Therefore, it needs to be modified to expand the application field of polyvinyl alcohol. At present, there are mainly the following...

AI Technical Summary

Problems solved by technology

For example, polyvinyl alcohol, methacryloyl chloride ethyl trimethyl ammonium chloride and glycidyl methacrylate are grafted, copolymerized and cross-linked, and the grafted cross-linked modified polyvinyl alcohol is used for internal sizing of paper pulp. Dry strength agent, which has obvious dry strengthening effect on paper, but there are few reports on the use of grafted cross-linked modified polyvinyl alcohol for paper surface sizing