The invention discloses a
papermaking dry strength agent preparation method, which comprises: S1, dissolving
chitosan in an acidic
aqueous solution to form a
chitosan glue solution, and removing
oxygen; s2, dropwise adding a high-concentration
acrylamide solution, a water-phase
monomer mixed solution and an initiator solution for graft copolymerization to obtain a branched
prepolymer; s3, a cross-linking agent is added for a cross-linking reaction, and a micro-cross-linked structure is formed; primary amino groups on a
chitosan chain are terminated, and branched amphoteric chitosan-
polyacrylamide dry strength agent
mother liquor is obtained; s4, carrying out composite dispersion on the
composite material and a
nanocellulose material, and diluting to obtain a
diluent; and S5, after a
paper machine slushing pump and before a pressurized screen, firstly adding an anionic garbage capturing agent for pre-
flocculation, then continuously feeding the
diluent, and stirring to obtain the product. According to the
papermaking dry strength agent prepared by the preparation method disclosed by the invention, the
interface bonding strength of the
papermaking dry strength agent to fibers and the adaptability and use efficiency of the papermaking dry strength agent in a complex wet end environment are remarkably improved, and the requirements of the modern papermaking industry on high-performance and high-stability dry strength agents can be met.