Determination of kinetic parameters of ethyl methacrylate polymerization by using the dead‐end procedure

Abstract

Kinetics of polymerization of ethyl methacrylate initiated by 2,2'-azoisobutyronitrile (AIBN) was studied applying the "dead-end" theory. This theory is appropriate to examine the solution polymerization of this monomer in benzene at 8 > 60°C. Radical polymerizations of ethyl methacrylate were carried out at 60 -110 "C. By using the procedures of the dead-end theory, the rate of decomposition and the initiator efficiency of AIBN were determined. Kinetic parameters of the solution polymerization of ethyl methacrylate were calculated and the results were compared with the literature values.

RAFT-Mediated Polymerization of Styrene in Readily Biodegradable Ionic Liquids

“…In ionic liquids, the initiator decomposition rate coefficient, k d , was found to remain relatively constant using UV−vis spectroscopy to monitor the loss of initiator with time . Since our polymerizations reached only 80% conversion after 14 h, we utilized the dead-end polymerization technique , (see Figure ), which allows the instantaneous determination of k d using eq to calculate it independently of all other kinetic parameters (e.g., f , k p , k t ). This technique was used to calculate k d in a conventional free-radical polymerization (Figure A) and for a RAFT-mediated polymerization (Figure B).…”

“…For polymerizations involving long reaction times and where initiator concentrations decrease to very low levels, the dead-end polymerization technique can be used to determine the rate coefficient of initiator decomposition. − At long reaction times, the reaction conversion, x , approaches a limiting value x f . Under these conditions, it can be shown that k d is related to the time, t , and conversion, x , via the following equation: − ln true[ 1 − ln ( 1 − x ) ln ( 1 − x f ) true] = k d t 2 Thus, k d can be easily determined by taking the initial slope from a plot of the left side of eq vs t .…”

Radical Chain Polymerization

“…A fourth method is the dead-end polymerization technique, which allows the simultaneous determination of k d [Catalgil and Baysal, 1987;Reimschuessel and Creasy, 1978;Stickler, 1979]. Dead-end polymerization refers to a polymerization in which the initiator concentration decreases to such a low value that the half-life of the propagating polymer chains approximates that of the initiator.…”