Experimental Study of AGET ATRP of MMA and BMA Homopolymerizations in Emulsion Batch Reactor

Abstract

<p>Controlled radical polymerization (CRP) is a fast-growing technique for the creation of nano-sized polymer particles. In particular, atom transfer radical polymerization (ATRP) is a promising catalytic CRP method that has been extensively studied in academia and industry. Due to the limited studies of ATRP in emulsion systems, the focus of this research project is to investigate an ATRP procedure initiated by an activator generated by an electron transfer (AGET) scheme in a 2L stirred tank emulsion reactor. The current research incorporates the environmental and sustainable aspects of benign technology.</p> <p>This thesis consists of four parts. The first investigation dealt with the compatibility of the surfactant-ligand design. For instance, hydrophobic ligands, which are very efficient in emulsion ATRP, are expensive and commercially not easily available. Therefore, a successful controlled polymerization system using an eco-friendly and low-cost hydrophilic like HMTA ligand and an anionic surfactant is examined in this research.</p> <p>In addition, the solubilities of the Triphenylphosphine (PPh3), 1, 10-Phenanthroline (Phenol), and Vitamin D ligands in the organic phase were evaluated to confirm the possibility of producing PMMA with controlled characteristics in an emulsion AGET ATRP technique.</p> <p>The second part of this thesis involves a detailed experimental study, which examined the effects of temperature, surfactant concentration, monomer water (M/W) ratio, and agitation speed on the characteristics of poly(methyl methacrylate) (PMMA). The results revealed that it is possible to achieve high monomer conversion at a mild temperature with a limited occurrence of coagulation.</p> <p>The third part of the thesis involves a kinetic study of emulsion ATRP. Literature reveals no detailed reports on chemical kinetics of emulsion ATRP. Thus, an empirical model was using experimental data collected in this study developed to describe the rate of polymerization in emulsion AGET ATRP. The results demonstrate that the behavior of ATRP in emulsion is significantly different from FRP in emulsion media.</p> <p>Lastly, a statistical analysis of poly(butyl methacrylate) PBMA was done using screening design of experiments approach. The results revealed that temperature, surfactant, stirring speed and temperature-surfactant interaction have significant effects on the conversion and the temperature and ligand have a more pronounced impact on the molecular weight distribution (MWD) of the final PBMA product.</p>