LUPASOL G 20 is a multifunctional cationic polyethyleneimine (PEI) with a branched polymer structure. Because of its high charge density, LUPASOL G 20 adsorbs strongly on negatively charged surfaces such as cellulose, polyester, polyolefins, polyamides, and metals. It is therefore used as an adhesion promoter for bonding different materials. The usual application rate for these applications is very low, in the 50 – 150 mg/m2 range. In addition, owing to the large number of peripheral amino groups, LUPASOL G 20 can act as a physical or chemical crosslinking agent in coatings, paints, and adhesives.