Fractionation of Latex-Based Adhesives and Paints by Isopycnic Centrifugation

Abstract

Latex-based adhesives and paints can be fractionated by isopycnic sedimentation in density gradients, generated by osmocentrifugation. Fractions were obtained from a PVA-based adhesive, which differed in tacticity, as observed by ¹H NMR; calcium carbonate was easily identified in another product, after fractionation. In an acrylic-based latex paint the pigments contained PVA, although this polymer was not detected in other fractions. These results show that low-speed isopycnic sedimentation in density gradients is a convenient, gentle, inexpensive, and powerful method to fractionate complex particle admixtures. A marked advantage of this method is its ability to give fractions large enough for examination by other analytical techniques.