MODEL-COMPOUND STUDY FOR ACRYLIC LATEX CROSS-LINKING REACTIONS WITH CYCLOALIPHATIC EPOXIDES

Cyclohexene oxide, methanol, and acetic acid were used as model compou nds to study competitive crosslinking of cycloaliphatic diepoxides wit h hydroxyl and carboxyl functionalized acrylic copolymers. Model react ions were performed as a function of molar ratio, pH, and temperature. At a 2:1:1 molar ratio of epoxide: hydroxyl : carboxyl, the formation of the primary ether and ester linkages were found to be the major cr osslinking reactions. By increasing the molar ratio to 3:1:1, the form ation of both the ether and ester oligomer products were significantly enhanced. As the pH of the median decreased, the rate of the crosslin king reactions increased, and generally ester products were formed pre ferentially to ether products. A temperature dependence of the rate of reactions were generally more pronounced at higher pH.