Reactivity ratio estimation: Two case studies.

Abstract

Two separate case studies on polymerization kinetics were performed. These studies focused on the determination of reactivity ratios: important copolymerization kinetic parameters. They are used to predict multicomponent polymer composition directly and have an indirect influence on the prediction of polymerization rate and final properties. In some cases, these parameters can be very difficult to obtain using standard techniques. These standard methods involve low conversion experiments and measurement of the final polymer composition. The goal of the first study was to determine the reactivity ratios of a copolymer system that presents significant experimental challenges. The study involved a small polymer chain, called a macromonomer copolymerized with acrylic or methacrylic acid monomers. The second case study involved the styrene/butyl acrylate copolymer system. Firstly, the reactivity ratios were estimated in bulk and in toluene solution. Gel permeation chromatography (GPC) was used to determine the weight-average molecular weight of selected styrene/butyl acrylate copolymer samples. An additional investigation focused on the use of attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectrometry was completed. (Abstract shortened by UMI.)