Fpinnovations

Pulp and Paper Research Institute of Canada

Chem Pro

Miroslav Antal

Ivan I Pikulik

Makhlouf Laleg

Xujun Hua

Jan Martin Strmen

Jarka Matous

Peter Volf

A new class of polymeric additives for papermaking is disclosed as well as a process for their manufacture, a method for their use and a paper sheet containing the addition. The additives can be used in paper manufacture as agents for improving retention, paper machine operation and the strength properties of the product. The additives are manufactured from a microbial biomass. The biomass that contains acetyl amino groups or other amides is chemically modified by hydrolysis of the amides to form primary amino groups. Under neutral or acidic conditions these primary amines become cationic, which assures a good absorption of the additive onto fibres and fines of pulp that is generally of anionic nature.

Papermaking additive

Disclosed is a method for manufacture and application of a polymeric papermaking additive, which can be used in paper manufacture as an agent for improving retention, drainage, product strength and paper machine operation. The additive according to this disclosure is a polymer of epichlorohydrin and contains primary amino groups. Under neutral or acidic conditions these primary amino groups become cationic, which assures good adsorption of the polymer onto anionic fibers and fines of pulps used for production of paper or paperboard. By adsorbing on several fibers or fines, the polymer can increase the retention of fines and fillers. Primary amino groups of this polymer can also form chemical bonds with carbonyl groups of cellulose, lignin and hemicellulose, which are especially abundant in the fibers and fines of mechanical pulps. The cross-linking of fibers and fines by chemical bonds can increase the initial strength of wet web and the strength of rewetted paper. Mechanical pulps contain high negative charge and tend to deactivate many conventional cationic polymers. Because of its high cationic charge and the ability to form chemical bonds with mechanical pulp, novel papermaking additive according to this invention is particularly suitable for improving the retention and the strength of paper made from fibrous pulp suspensions that contain at least a portion of mechanical pulp. If the polymer has a high molecular weight it can be use as a single component retention and strength additive. If the polymer has a relatively low molecular weight, it can be conveniently used as coagulant and can be combined with a high-molecular-weight, low-charge-density polymer that serves as a flocculent.

Epichlorohydrin-based polymers containing primary amino groups used as additives in papermaking

A graft polymer comprises a carbohydrate polymer having pendant 3-amino-2-hydroxy propyl groups grafted thereon and may be employed as a retention aid and strengthening additive in paper manufacture. When the carbohydrate polymer is a component of wood pulp the resulting chemically modified wood pulp may be employed in conjunction with unmodified wood pulp to incorporate therein the retention and strengthening characteristics.

Papermaking additives and mechanical pulp with primary amino groups

Growing community of inventors

Pointe Claire, Canada

Miroslav Antal