Research And Development Of Modified PAE Resin For Paper Dry Strength Agents

Based on the enhancement theory of hydrogen bonds is recognized in thepaper academia, starch is widely used as dry strength agent in the global paperindustry,which has positive effect for increasing paper ash content and surfacestrength. However, its technical potential has basically been excavated, and it isdifficult to meet the needs of enhancement. Meanwhile, with the development ofthe paper industry, the adverse effect of the use of starch is rising. In order tomeet the needs of high enhancement of the paper, papermakers are looking for anew strength agent, but what to choose has not yet formed a unifiedunderstanding. The paper is studied the character of the PAE resin using as drystrength agent, and discuss the modification process and influence of carboxylmodification, hydroxyl modification, mixing carboxyl and hydroxyl modificationPAE resin and esterification modification PAE resin.The research result is shown as flowing:Carboxyl modification PAE resin can decrease the wet strength and greatlyincrease the dry strength of paper. The effect of end modification is better thanintermediate modification, and the best addition amount is9%. When dosage is0.5%, compared to traditional PAE resin, dry tensile index of the paper ofmodification PAE resin is further increased by about11%, and wet tensile indexis decreased by about8%, folding endurance degree is increased by about17%,tearing index is increased by about27%, and the bond strength is increased byabout47%.The effect of hydroxyl end modification PAE is better than intermediatemodification, which can decrease the wet strength and increase the dry strengthof paper, and the best addition amount is15%. When dosage is0.5%, comparedto traditional PAE resin, dry tensile index of the paper of modification PAE resinis further increased by about7%, and wet tensile index is decreased by about23%, folding endurance degree is increased by about13%, tearing index is increased by about25%, and the bond strength is increased by about42%.Carboxyl and hydroxyl together modification PAE can decrease the wetstrength and greatly increase the dry strength of paper. The effect of endmodification is better than intermediate modification, and the best additionamount is20%. When dosage is0.5%, compared to traditional PAE resin, drytensile index of the paper of modification PAE resin is further increased by about12%, and wet tensile index is decreased by about21%, folding endurance degreeis increased by about21%, tearing index is increased by about33%, and thebond strength is increased by about48%.The best addition amount of etherifying agent of etherification modificationPAE resin is15%, and the effect of end modification is better than intermediatemodification. When modified PAE resin dosage was0.5%, compared totraditional PAE resin,dry tensile index of the paper of modification PAE resin isfurther increased by about3%, and wet tensile index is decreased by about19%,folding endurance degree is increased by about9%, tearing index is increased byabout19%, and the bond strength is increased by about37%.Carboxyl/hydroxyl blending modification is the best one of the fourmodification methods. When use the carboxyl/hydroxyl blending modificationPAE resin, both covalent bond and hydrogen bond are generated in the networkstructure of paper. The covalent bond and hydrogen bond are interfingering andgenerate synergistic effect, and the effect of enhancement is improved.