Polyaddition based comb-like wetting and dispersing additives for aqueous and non-aqueous systems

János Hajas, Dr.Stefan Mössmer, Dr.Jürgen Omeis, Dr.Ulrich Orth, Monika Roch, BYK-Chemie GmbH, Germany

A new concept has been developed to build high molecular weight polymeric comb-like structures, suitable as wetting and dispersing additives. The concept utilizes a backbone, built up from epoxide-functional and amine functional molecular segments, which form a linear polyaddition product, carrying both aminic and repeating OH groups along the chain. This OH function can be used in a second reaction step to put side chains through an addition reaction with NCO functional longer tail molecules. Depending on the polarity of the side chains, the resulting molecules can be used either for aqueous or for non-aqueous pigment dispersions. Application tests show excellent viscosity reduction, very good gloss and transparency, and high effectiveness / lower dosage level in various millbases, compared to the “classic” and even newer types of polymeric wetting and dispersing additives (polyurethanes, random polyacrylates, comb-like polyacrylates) . The new technology shows very promising results for many technical applications, from automotive coatings up to printing inks.