On the design of polymers for increased paper dry strength: A review

Water-borne polymers are routinely added the papermaking process to increase the mechanical strength of dry paper. Reviewed are the relationships between the chemical structures of the dry strength polymers and their influence on paper strength. The degree of cationic charge, the molecular weight and the presence of reactive groups on the polymer do not directly influence dry paper strength. Polymer hydrophobicity/hydrophilicity seems to be a predictor of efficacy - the more hydrophilic, the stronger the paper.