Control of functional site location for thermosetting latexes

Journal of Coatings Technology and Research (Impact Factor: 1.3). 02/2009; 6(1):27-36. DOI: 10.1007/s11998-008-9099-3


The location of hydroxyl functionality was investigated for thermosetting acrylic latexes. Large and small latex particles
with and without hydroxyl functionality were also synthesized and characterized. Large and small latex particles with and
without hydroxyl functionality were blended together, and the latexes were crosslinked. The location of hydroxyl groups in
the small or large latex particles had an effect upon the thermomechanical properties and hence on the ultimate performance
of the crosslinked latexes. The packing of the large and small latexes was dependent on small-to-large particle ratio, and
in addition had an effect upon the speed of film formation. The higher concentration of hydroxyl groups in the small latex
particles contributed more to the tensile properties of the latexes than the functionality of the large particles.

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