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Copolymerization of n ‐Butyl Acrylate and Styrene: Terminal vs Penultimate Model
Author(s) -
Hamzehlou Shaghayegh,
Reyes Yuri,
Hutchinson Robin,
Leiza Jose Ramon
Publication year - 2014
Publication title -
macromolecular chemistry and physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.57
H-Index - 112
eISSN - 1521-3935
pISSN - 1022-1352
DOI - 10.1002/macp.201400263
Subject(s) - copolymer , styrene , branching (polymer chemistry) , polymer chemistry , monomer , butyl acrylate , acrylate , chemistry , materials science , polymer , organic chemistry
The batch solution copolymerization of styrene and n‐ butyl acrylate over a range of styrene feed compositions is analyzed by in situ 1 H NMR to monitor individual and overall monomer conversions, as well as by 13 C NMR and size exclusion chromatography (SEC)/multi‐angle light scattering (MALS) for the branching density and molecular weight, respectively. Both the terminal and penultimate models, using rate coefficients taken from the literature, fail to predict the full extent of the reduced overall copolymerization rate observed when the styrene composition in the feed is increased. After estimation of uncertain model parameters, the terminal model provides a good representation of the experimental dataset. The estimated overall efficiency of the initiator decreases (from the typically employed 0.65 to 0.35) and the cross‐termination increases from the values corresponding to the geometric mean of the homopolymerization termination rate coefficients.