TY - JOUR
T1 - Reversible addition fragmentation chain transfer copolymerization
T2 - Influence of the RAFT process on the copolymer composition
AU - Feldermann, Achim
AU - Ah Toy, Andrew
AU - Phan, Hong
AU - Stenzel, Martina H.
AU - Davis, Thomas P.
AU - Barner-Kowollik, Christopher
PY - 2004/1/1
Y1 - 2004/1/1
N2 - Reversible addition fragmentation chain transfer (RAFT) mediated and conventional copolymerizations at low monomer conversions have been carried out for the systems methyl methacrylate (MMA)-styrene, methyl acrylate (MA)-styrene and methyl methacrylate-butyl acrylate (BA). The polymer samples have been analyzed via 1H-NMR spectroscopy to obtain the copolymer composition and the terminal model reactivity ratios. In the RAFT mediated copolymerizations, the polymer mole fraction of the monomer with the larger reactivity ratio is increased compared to the conventional copolymerization. Simulations have been carried out using the program package PREDICI ® to examine possible explanations for the experimental findings. The simulations demonstrate that the RAFT process itself may alter the macroradical populations and the copolymer composition by offering additional reaction pathways. Further, the rate coefficients for the initiation reaction and the pre-equilibrium play an important role in determining the copolymer composition. The rate coefficients governing the main equilibrium of the RAFT process have only a minor impact on the copolymer composition.
AB - Reversible addition fragmentation chain transfer (RAFT) mediated and conventional copolymerizations at low monomer conversions have been carried out for the systems methyl methacrylate (MMA)-styrene, methyl acrylate (MA)-styrene and methyl methacrylate-butyl acrylate (BA). The polymer samples have been analyzed via 1H-NMR spectroscopy to obtain the copolymer composition and the terminal model reactivity ratios. In the RAFT mediated copolymerizations, the polymer mole fraction of the monomer with the larger reactivity ratio is increased compared to the conventional copolymerization. Simulations have been carried out using the program package PREDICI ® to examine possible explanations for the experimental findings. The simulations demonstrate that the RAFT process itself may alter the macroradical populations and the copolymer composition by offering additional reaction pathways. Further, the rate coefficients for the initiation reaction and the pre-equilibrium play an important role in determining the copolymer composition. The rate coefficients governing the main equilibrium of the RAFT process have only a minor impact on the copolymer composition.
KW - H-NMR spectroscopy
KW - Polymerization kinetics
KW - Reversible addition fragmentation chain transfer (RAFT) copolymerization copolymer composition
UR - http://www.scopus.com/inward/record.url?scp=2442617197&partnerID=8YFLogxK
U2 - 10.1016/j.polymer.2004.04.016
DO - 10.1016/j.polymer.2004.04.016
M3 - Article
AN - SCOPUS:2442617197
SN - 0032-3861
VL - 45
SP - 3997
EP - 4007
JO - Polymer
JF - Polymer
IS - 12
ER -