polyacrylamid

Polyacrylamide, often abbreviated PAM and known in German as Polyacrylamid, is a synthetic polymer derived from the monomer acrylamide. It is produced by free-radical polymerization to form long chains of repeating vinyl units featuring amide groups. PAM can exist as a linear, water-soluble polymer or, when crosslinked with a bifunctional agent such as N,N'-methylenebisacrylamide, as an insoluble gel. Partially hydrolyzed PAM (HPAM) introduces carboxylate groups, increasing charge density and enabling anionic or cationic variants through copolymerization.

PAM’s properties depend on its structure. Linear PAM is water-soluble, while crosslinked PAM forms hydrogels suitable for electrophoresis and other gel-based applications. The charge and solubility can be tuned by hydrolysis or by incorporating comonomers, producing nonionic, anionic, or cationic variants.

Common applications are wide-ranging. In water and wastewater treatment, PAM acts as a flocculant and clarifier. In mining and mineral processing, it aids solid-liquid separation. In papermaking, PAM serves as a retention and drainage aid. It is also used as a soil conditioner and erosion-control agent. In biochemistry and molecular biology, crosslinked polyacrylamide gels are used for electrophoresis and chromatography.

Safety and environmental notes: residual acrylamide monomer is toxic and regulated due to neurotoxic and potential carcinogenic effects. The polymer itself is generally of low toxicity but is not readily biodegradable, and crosslinked forms persist in the environment. Proper handling and adherence to regulatory guidelines are recommended.