Macromolecules
Article
UV light to generate radicals was unlikely to lead to a
completely different polymerization mechanism;14 however, as
reported previously, the polymer chain ends were not perfectly
stable under UV exposure, and they cleaved to form additional
polymer radicals and thiocarbonylthio radicals (photoiniferter
pathway). Because the persistent radical effects of the
thiocarbonylthio radicals were not as dominant as in the
nitroxide-mediated polymerization or in atom transfer radical
polymerization reactions, conditions that favored the photo-
iniferter pathway resulted in the loss of control over the
polymerization reaction. The higher degree of control afforded
by the present system compared to conventional photoiniferter
processes suggested that the present system mainly proceeded
through a RAFT process. At this stage, it is difficult to
determine the ratio of the prevalence of each pathway because
the polymers generated by RAFT or photoiniferter mechanisms
would yield identical structures.34
ACKNOWLEDGMENTS
■
This work was supported by the Basic Science Research
Program through the National Research Foundation of Korea
(NRF) funded by the Ministry of Education, Science and
Technology (NRF-2010-0010871) and the Human Resources
Development of the Korea Institute of Energy Technology
Evaluation and Planning (KETEP) grant funded by the
Ministry of Knowledge Economy (No. 20124030200070),
Republic of Korea
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CONCLUSION
■
In summary, CPEC was successfully designed for the controlled
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* Supporting Information
UV−vis absorption spectra of CPEC and AIBN decomposition
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AUTHOR INFORMATION
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(23) Debuigne, A.; Caille, J.-R.; Jer
1125−1128.
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K.; Kwak, Y.; Goto, A.; Fukuda, T. J. Am. Chem. Soc. 2004, 126,
13908−13909.
́ ̂
ome, R. Angew. Chem. 2005, 117,
Corresponding Author
Notes
The authors declare no competing financial interest.
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dx.doi.org/10.1021/ma5002244 | Macromolecules 2014, 47, 1929−1934