The free‐radical terpolymerisation of ethylene, methyl acrylate and vinyl acetate at high pressure. Polymerization tests

Abstract

In this study, the terpolymerisation, under high pressure, has been examined for the ethylene-methyl acrylate-vinyl acetate system. The polymerisations were carried out in a high pressure polymerisation facility designed for continuous operation. To assess the effect of pressure and temperature on the reaction, polymerisation was carried out at two different pressures of 1900 and 1 100 bar and at temperatures of 180 and 230 "C. By varying the concentration of the ethylene, methyl acrylate and vinyl acetate monomers in the feed, polymers of different composition were obtained. The ratio of the monomer concentrations in the reactor was calculated from the amount of polymer weighed out and its comonomer content as well as the composition of the feed, using the mass balance for the ideal stirred tank reactor. The result was used to determine the reactivity ratios of the three possible binary copolymerisation systems ethylene/ methyl acrylate, ethylene/vinyl acetate and methyl acrylate/vinyl acetate. This made it possible to predetermine, by calculation, the composition of a product obtained by continuous polymerisation in a stirred autoclave.

Theoretical Study of Ethylene−Vinyl Acetate Free-Radical Copolymerization: Reactivity Ratios, Penultimate Effects, and Relative Rates of Chain Transfer to Polymer

“…More recent high pressure (2000 atm, ca. 200 °C) terpolymerization results 31,32 place the value of r 1 close to 0.9 and the value of r 2 in the range 0.9-1.7.…”

Design of Optimal Experiments for Terpolymerization Reactivity Ratio Estimation

“…Given the importance of terpolymerization systems and such a significant gap in the literature for this problem, our recent publication provides a thorough investigation for estimating reactivity ratios in ternary systems. That work, while discussing the very few attempts for direct estimation of reactivity ratios from terpolymerization data (see, e.g., Duever et al, Iglesias et al, and Luft et al), presented a reliable approach for estimating ternary reactivity ratios using the recast model, as shown in Equation (1)–(3), and the EVM parameter estimation technique. Herein, Section 3.2 shows the EVM methodology and examples of its implementation for ternary problems are discussed in the “Results and Discussion” Section 4.…”

Free‐Radical Polymerization in Reactive Supercritical Fluids

“…To reduce scope and complexity, only binary copolymerization systems are considered. Regarding high-pressure polymerizations with more than two monomers, the ternary systems ethene-vinyl acetate-acrylonitrile and ethene-vinyl acetate-methyl acrylate are described in References [43] and [44], respectively.…”