Macromolecules
ARTICLE
range of pH values that induced the thermal transition within the
given temperature ranges.
pH-Tunable Thermal Transition: In-Situ H NMR Studies.
’ ACKNOWLEDGMENT
This work was supported by the WCU research program
R33-2008-000-10003), Priority Research Center Program
2009-0093818), and Basic Science Research Program (2010-
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(
(
pH-dependent thermal transition behaviors of P-2 observed by
UV-vis studies correlated with in-situ temperature-dependent
0
008642) through the National Research Foundation of Korea
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H NMR measurements in deuterated water. P-2 was chosen
funded by the Ministry of Education, Science, and Technology
of Korea.
since it showed thermal transitions over a broad range of pH
values. Contrary to the percent transmission studies by UV-vis,
which determined the macroscopic, intermolecular aggregation
1
trend, H NMR spectroscopy can provide information on
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1
H NMR spectra of 0.01 wt % aqueous solution of P-2 at pH
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8
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Similar trends were observed for pH 8.5 and 9.0, except the
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4
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(39 °C) for pH 8.0 where the integral area dropped abruptly.
(
This onset temperature where peak intensities started to de-
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(
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determined by in-situ temperature-dependent H NMR almost
(
matched with those values determined beforehand by percent
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(
(
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CONCLUSIONS
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(
synthesized using ATRP and click reactions. The transmission
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(
(
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perature-dependent H NMR measurements in deuterated water
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AUTHOR INFORMATION
No. 16, 2106–2108.
Corresponding Author
(29) Yamamoto, S.-i.; Pietrasik, J.; Matyjaszewski, K. Macromolecules
2008, 41 (19), 7013–7020.
*E-mail: sims0904@ulsan.ac.kr.
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dx.doi.org/10.1021/ma102751p |Macromolecules 2011, 44, 1628–1634