M.S. (Master of Science)
Department of Chemistry and Biochemistry
Waterborne acrylic latex makes up a vast majority of the architectural coatings market, including most of the paints sold in retail stores. Most, if not all, of these latex formulations are prepared using radical polymerization of acrylic monomers. Reversible addition-fragmentation chain-transfer (RAFT) polymerization has been researched for over two decades, but to this point has made very little progress finding success in commercial applications. Indeed, a majority of RAFT research has been dedicated to successfully polymerizing different monomers with good degree of polymerization control, and very little research has been directed toward actual coating applications. In this study, we focused on optimization of the RAFT process for making acrylic latex polymers that are realistic for making architectural coatings. Once a suitable RAFT agent was chosen, the process to consistently prepare polymers with good RAFT control was optimized. This optimized process was used to develop a series of RAFT polymers to test against a standard emulsion polymer of the same composition using a series of coating industry standards. In this work, we showed that an effective macroRAFT agent could be prepared by utilizing a poly(acrylic acid) chain of 40 units end-capped with a trithiocarbonate RAFT agent. This macroRAFT agent could be used to further copolymerize methyl methacrylate and n-butyl acrylate, as well as prepare block copolymers of varying ratios with a good degree of structure, molecular weight and dispersity control. Paints were then made with the resulting RAFT polymers, which were tested in a number of typical coatings test methods. The results of the testing showed not only that the RAFT emulsion acrylic latex formulations were feasible for use in these types of coatings, but many of the tests also showed that they outperformed the coatings made from the latex emulsions prepared using traditional radical polymerization.
Balgeman, Andrew, "Reversible Addition-Fragmentation Chain-Transfer Emulsion Polymerization and its Application to Waterborne Coatings" (2021). Graduate Research Theses & Dissertations. 6838.
Northern Illinois University
Rights Statement 2
NIU theses are protected by copyright. They may be viewed from Huskie Commons for any purpose, but reproduction or distribution in any format is prohibited without the written permission of the authors.