5094
H. Okamura, M. Shirai / Polymer 51 (2010) 5087e5094
photoinduced-acid catalyzed cross-linking reaction of epoxy moiety
of Gn-TriEpo and phenolic eOH units in PVP. It is noteworthy that
complete insolubilization was observed for the PVP/G3-TriEpo
blended films. The high efficiency for the cross-linking was due to
high functionality of the dendrimer.
21350128. The authors thank Prof. Y. Tsujii and Dr. A. Goto at Insti-
tute for Chemical Research, Kyoto University, Japan for a MALLS-SEC
analysis.
Appendix. Supplementary material
When the blended films were baked at 140 ꢀC for 10 min after
irradiation, complete dissolution of the film was observed.
The re-insolubilization for the blended films on baking at above
160 ꢀC for 10 min was due to the reaction of the eOH groups in PVP
and corresponding carboxylic acid generated from the thermolysis
of the dendrimers. The results were essentially the same as those
for PVP/crosslinker system [26] except for the high efficiency of
cross-linking.
Supplementary material associated with this article can be
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Acknowledgments
This work was supported by the Ministry of Education, Science,
Sports, and Culture, Grant-in-Aid for Scientific Research (B)(2) No.