EFFECT OF A COFACTOR ON THE POLYMER BRIDGING OF LATEX-PARTICLES TO GLASS BY POLYETHYLENE OXIDE

Polymer bridging by high molecular weight polyethylene oxide (PEG) is enhanced by a cofactor, usually a low molecular weight phenolic compou nd. PEG-cofactor systems are widely used in papermaking as a so-called retention aid. In this study the effects of one particular cofactor, sulfonated kraft lignin (SKL), on polymer bridging by PEG, was investi gated. The deposition of latex spheres on a glass surface coated by PE O was observed with the impinging jet technique. The deposition kineti cs were mainly controlled by electrostatics, since both the latex part icles and the PEO-SKL complexes formed at the surface are negatively c harged. The detachment kinetics were strongly affected by SKL as the f raction of very strongly bound particles increased. At SKL concentrati ons above 1 mg l(-1) it took longer for the weakly bound particles to detach. These studies show that SKL strengthens the PEO bridge between latex and glass.