Water-soluble/dispersible cationic pressure-sensitive adhesives. II. Adhesives from emulsion polymerization



In our previous work, we reported that cationic water-soluble pressure-sensitive adhesives (PSAs) could be synthesized in ethanol or methanol. These cationic water-soluble adhesives would not cause a stickies problem during paper recycling and can be easily removed from the papermaking system by adsorbing on wood fibers. In this study we report the synthesis and application of water-based cationic PSAs using miniemulsion polymerization. A redox initiator system of cumene hydroperoxide/tetraethylenepentamine was used to force interfacial polymerization. The end-use properties of the PSAs were evaluated, and the repulpability of the PSAs in paper recycling was studied. It was found that the cationic PSA from miniemulsion polymerization itself was insoluble and nondispersible in water during the paper recycling process. However, if this water-insoluble cationic PSA from miniemulsion was formulated with a water-soluble cationic PSA made from ethanol, the solubility or dispensability of the former PSA in water was improved. The molecular weight and degree of crosslinking of the PSA polymer have significant effects on the properties and dispersability of PSA. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 347–353, 2004