In:
Macromolecular Theory and Simulations, Wiley, Vol. 30, No. 6 ( 2021-12)
Abstract:
Electron paramagnetic resonance (EPR) spectra of the ensemble of growing macroradicals are recorded during the radical copolymerization of styrene‐d8 and methyl methacrylate (MMA) for various comonomer compositions and subsequently modeled by MATLAB in combination with EasySpin simulations. Fully deuterated styrene‐d8 is used to simplify the EPR spectra and to allow a clear assignment of the EPR‐signals to the two different terminal units. By that approach, the macroradical fraction having styrene‐d8 as terminal unit, Φ s , could directly be determined from the copolymerization spectra without concentration calibration. The so‐obtained Φ s values could not be described by the penultimate model using the literature‐reported set of reactivity ratios. Consequently, Φ s, the copolymer composition, and the overall propagation rate coefficient are adjusted in small steps simultaneously using Excel arriving at a new and more reliable set of reactivity ratios for the copolymerization of styrene and MMA.
Type of Medium:
Online Resource
ISSN:
1022-1344
,
1521-3919
DOI:
10.1002/mats.202100048
Language:
English
Publisher:
Wiley
Publication Date:
2021
detail.hit.zdb_id:
1475028-4