Browse > Article
http://dx.doi.org/10.5012/bkcs.2009.30.7.1521

Thermosensitive Block Copolymers Consisting of Poly(N-isopropylacrylamide) and Star Shape Oligo(ethylene oxide)  

Lee, Seung-Cheol (Department of Materials Science and Engineering, Seoul National University)
Chang, Ji-Young (Department of Materials Science and Engineering, Seoul National University)
Publication Information
Bulletin of the Korean Chemical Society / v.30, no.7, 2009 , pp. 1521-1525 More about this Journal
Abstract
Thermosensitive block copolymers of ethylene oxide and N-isopropylacrylamide (NIPAM) were synthesized. A five armed star shape oligo(ethylene oxide) initiator with a cyclotriphosphazene core was prepared and used for the atom transfer radical polymerization (ATRP) of NIPAM. The lower critical solution temperatures (LCSTs) of the copolymers were 36 to 46 ${^{\circ}C}$, higher than that of PNIPAM (32 ${^{\circ}C}$), depending on their molecular weights. The copolymers were soluble in water below the LCSTs but formed micelles above the LCSTs. The thermosensitive micellization behaviors of the polymers were investigated by fluorescence spectroscopy. With increasing the temperature of an aqueous solution of P2 and pyrene above the LCST, the peak of 333 nm red-shifted to appear around 339 nm and its intensity increased significantly, indicating the micelle formation. The transfer of pyrene into the micelles was also confirmed by a confocal laser scanning microscope. The fluorescence image obtained from P2 in an aqueous pyrene solution exhibited a green emission resulting from the pyrene transferred into the micelles. Salt effects on the solubility of the copolymers in an aqueous solution were investigated. The LCST of P2 decreased sharply as the concentration of sodium chloride increased, while decreased slowly with potassium chloride.
Keywords
Block copolymers; Thermosensitive polymers; Lower critical solution temperature; Cyclotriphosphazene;
Citations & Related Records
Times Cited By KSCI : 4  (Citation Analysis)
Times Cited By Web Of Science : 4  (Related Records In Web of Science)
Times Cited By SCOPUS : 3
연도 인용수 순위
1 Gobbi, A.; Landini, D.; Maia, A.; Delogu, G.; Podda, G. J. Org. Chem. 1994, 59, 5059   DOI   ScienceOn
2 Blonsky, P. M.; Shriver, D. F.; Austin, P. E.; Allcock, H. R. J. Am. Chem. Soc. 1984, 106, 6854   DOI
3 Blonsky, P. M.; Shriver, D. F.; Austin, P. E.; Allcock, H. R. Solid State Ionics 1986, 18/19, 258   DOI   ScienceOn
4 Allcock, H. R.; Olmeijer, D. L.; O'Connor, S. J. M. Macromolecules 1998, 31, 753   DOI   ScienceOn
5 Jun, Y. J.; Min, J. H.; Ji, D. E.; Yoo, J. H.; Sohn, Y. S. Bull. Korean Chem. Soc. 2008, 29, 2323   DOI   ScienceOn
6 Shin, Y. J.; Park, C. S.; Lee, C. I.; Shin, J. S. Bull. Korean Chem. Soc. 2008, 29, 2005   DOI   ScienceOn
7 Ciampolini, M.; Nardi, N. Inorg. Chem. 1966, 5, 41   DOI
8 Furyk, S.; Zhang, Y.; Ortiz-Acosta, D.; Cremer, P. S.; Bregbreiter, D. E. J. Polym. Sci. Polym. Chem. 2006, 44, 1492   DOI   ScienceOn
9 Inomata, H.; Goto, S.; Otake, K.; Saito, S. Langmuir 1992, 8, 687   DOI
10 Suwa, K.; Yamamoto, K.; Akashi, M.; Takano, K.; Tanaka, N.; Kunugi, S. Colloid Polym. Sci. 1998, 276, 529-533   DOI   ScienceOn
11 Kim, H. J.; Kim, S. H.; Quang, D. T.; Kim, J. H.; Suh, I.-H.; Kim, J. S. Bull. Korean Chem. Soc. 2007, 28, 811   DOI   ScienceOn
12 Okada, T. Analyst 1993, 118, 959   DOI   ScienceOn
13 Zhang, Y.; Furyk, S.; Bergbreiter, D. E.; Cremer, P. S. J. Am. Chem. Soc. 2005, 127, 14505   DOI   ScienceOn
14 Landini, D.; Maia, A.; Corda, L.; Maccioni, A.; Podda, G. Tetrahedron Lett. 1989, 42, 5781
15 Bergbreiter, D. E.; Case, B. L.; Liu. Y. S.; Caraway, J. W. Macromolecules 1998, 31, 6053   DOI   ScienceOn
16 Yoshida, R.; Uchida, K.; Kaneko, Y.; Sakai, K.; Kikuchi, A.; Sakurai, Y.; Okano, T. Nature 1995, 374, 240   DOI   ScienceOn
17 Liang, D.; Zhou, S.; Song, L.; Zaitsev, V. S.; Chu, B. Macromolecules 1999, 32, 6326   DOI   ScienceOn
18 Virtanen, J.; Tenhu, H. Macromolecules 2000, 33, 5970   DOI   ScienceOn
19 Zhu, P. W.; Napper, D. H. Langmuir 2000, 16, 8543   DOI   ScienceOn
20 Virtanen, J.; Holappa, S.; Lemmetyinen, H.; Thenhu, H. Macromolecules 2002, 35, 4763   DOI   ScienceOn
21 Mitokawa, R.; Morishita, K.; Koizumi, S.; Nakahira, T.; Annaka, M. Macromolecules 2005, 38, 5748   DOI   ScienceOn
22 Neradovic, D.; Soga, O.; Nostrum, C. F. V.; Hennink, W. E. Biomaterials 2004, 25, 2409   DOI   ScienceOn
23 Zhang, W.; Shi, L.; Wu, K.; An, Y. Macromolecules 2005, 38, 5743   DOI   ScienceOn
24 Kim, K. H.; Kim, J.; Jo, W. H. Polymer 2005, 46, 2836   DOI   ScienceOn
25 Choi, M. G.; Kim, H. J.; Chang, S.-K. Bull. Korean Chem. Soc. 2008, 29, 567   DOI   ScienceOn
26 Zintchenco, A.; Ogris, M.; Wagner, E. Bioconjugate Chem. 2006, 17, 766   DOI   ScienceOn
27 Qui, Y.; Park, K. Adv. Drug Delivery Rev. 2001, 53, 312
28 Chytry, V.; Ulbrich, K. J. Bioact. Compat. Polym. 2001, 16, 427   DOI   ScienceOn
29 Jydegaard-Axelsen, A. M.; Hoiby, P. E.; Holmstrom, K.; Russell, N.; Knochel, S. Appl. Environ. Microb. 2004, 70, 4111   DOI   ScienceOn