Composition and process for increasing the dry strength of a paper product

摘要

A dry strength additive composition generally includes an anionic and/or amphoteric polyacrylamide having a molecular weight of less than 1,000,000 Daltons, wherein the amphoteric polyacrylamide has a net negative charge; a cationic and/or amphoteric starch; and a cationic non-starch polymer having a charge density greater than 1 milliequivalent per gram (meq/g) at a pH of 3. The components defining the composition can be added to a pulp suspension sequentially or as a pre-blended mixture.

主权项

1. A dry strength additive composition comprising:
an anionic and/or amphoteric polyacrylamide having a molecular weight of less than 500,000 Daltons, wherein the amphoteric polyacrylamide has a net negative charge; a cationic and/or amphoteric starch; and a cationic non-starch polymer, wherein the composition has an overall net positive charge, wherein the cationic non-starch polymer is selected from the group consisting of: a dimethylamine-epichlorohydrin polymer, a dimethyldiallylammonium chloride homopolymer or copolymer, a polymeric quaternary ammonium compound, and a combination thereof; and wherein the anionic and/or amphoteric polyacrylamide to the cationic starch is at a weight ratio range from 5:1 to 1:2.