Guanidinyl ligand-functionalized polymers, methods of making the same, and substrates bearing a grafted coating of the ligand-functional polymers are described. The grafted polymer has the requisite affinity for binding neutral or negatively charged biomaterials, such as cells, cell debris, bacteria, spores, viruses, nucleic acids, endotoxins and proteins, at pH's near or below the pI's of the biomaterials.

A dispersion having a cationic zeta potential for use as a base coating on a sheet of paper or paperboard as a primer for a functional barrier top coating, wherein the composition comprises an anionic pigment containing mixture comprising one or more anionic pigments in an amount of at least about 20% dry weight of the mixture, and one or more polyamine-epihalohydrin cationic wet strength resin.

The invention relates to a method for dissolving cationic starch. In the method is obtained an aqueous polyelectrolyte solution comprising a synthetic cationic polymer, which has a charge density value of at least 0.1 meq/g, determined at pH3, the concentration of the cationic polymer in the polyelectrolyte solution being >2.5 weight-%, and the aqueous polyelectrolyte solution is brought together with cationic starch having a degree of substitution, DS, >0.1. The cationic starch is dissolved to the polyelectrolyte solution by heating and/or mixing. The invention relates also to a papermaking agent comprising 2-40 weight-% of synthetic cationic polymer which has a charge density value of at least 0.1 meq/g, determined at p H 3, and 2.5-25 weight-% cationic starch having degree of substitution, DS, >0.1. The papermaking agent is in slurry form and has a viscosity of 50-20 000 m Pas, measured at 25 C. with Brookfield DVI+ viscometer.

Polymer complex obtained by polymerization of water-soluble monomers: in the presence of a host polymer comprising vinylamine functions and of a non-polymeric transfer agent, and in the absence of branching or crosslinking agent of ethylenic polyfunctional type.