Polymer Reaction Engineering, Vol.11, No.3, 319-334, 2003
Alkyd/acrylic hybrid latexes with enhanced oxidative curing
Development of low or near zero volatile organic content (VOC) containing coatings has become a high priority for the coatings industry. As a result traditional solvent-borne resins such as alkyds have come into disfavor relative to waterborne resins such as acrylic based latexes. However, some combinations of properties such as ambient curing and high gloss have been difficult to achieve with acrylic-based latexes. Blends of alkyds and acrylic based latexes often suffer from incompatibility of the two polymer types resulting in hazy or non-uniform films. Properly designed hybrid systems, however, overcome compatibility issues associated with blends and generate property combinations that can not be obtained with either polymer system alone. Miniemulsion polymerization provides an effective processing method for combining alkyd and acrylic based polymers and delivering the resultant hybrid as a waterborne latex. This work describes the development of alkyd/acrylic hybrid latexes made via a miniemulsion polymerization process. Moreover, it describes how oxidative curing of the resultant polymer film can be markedly enhanced through the use of latent-oxidative functional monomers.