| 학회 | 한국고분자학회 |
| 학술대회 | 2005년 가을 (10/13 ~ 10/14, 제주 ICC) |
| 권호 | 30권 2호 |
| 발표분야 | 고분자 합성 |
| 제목 | Synthesis of Coil-Rod-Coil Poly(2-vinyl pyridine)-block-poly(n-hexyl isocyanate)-block-poly(2-vinyl pyridine) by Living Anionic Polymerization |
| 초록 | Rod-coil block copolymers have attracted an increasing interest due to their self-assembly behavior and capability of forming various supramolecular structures1. Phase separation behavior due to their inherent immiscibility offers the opportunity to study their morphology on a nanometer scale. The coil-rod or rod-coil-rod block copolymers of isocyanates with vinyl monomers has been synthesized by using one or two directional initiators, but the molecular weight distribution (MWD) could not be controlled2. In these system vinyl monomer were polymerized first and then isocyanates were added as a second monomer. The sequential addition of monomer starting from the isocyanates is not possible since the nucleophilicity of the living polyisocyanate block does not match the electron affinity of the second monomer. So the well defined triblock copolymer coil-rod-coil bearing the rigid part in the middle has not been reported. Our group is involved in the controlled synthesis of polyisocyanates and its copolymers. We have achieved novel synthetic method of rod-coil diblock copolymers of 2-vinyl pyridine (2-VP) and rod-coil-rod triblock copolymers of isoprene, styrene, and isocyanate via anionic polymerization.3 Recently we succeeded in quantitative end-capping of the living poly(n-hexyl isocyanate) (PHIC) with a number of aliphatic acid chlorides by using sodium benzanide (NaBA) as the initiator.4 It open up the new possibility of quantitative coupling reaction of AB diblock copolymer having PHIC living block with difunctional materials to synthesize novel coil-rod-coil triblock copolymers. We synthesized coil-rod-coil triblock copolymer of Poly(2-vinyl pyridine)-b-poly(n-hexyl isocyanate)-b-poly(2-vinyl pyridine) (P2VP-b-PHIC-b-P2VP) by coupling the precursor living polymers P2VP-b-PHIC prepared by anionic polymerization using potassium diphenylmethane (DPM-K), as the initiator in the presence of NaBPh4 as the additive. For the coupling reaction we used acid dihalides, viz. suberoyl and citramalic diacid chlorides, in the presence of pyridine. The coupling reaction was very efficient in that it led to the desired coil-rod-coil triblock copolymer in 100% yield. This novel amphiphilic block copolymers form spherical nano micelle to micro size vesicle micelle in selective solvents. References 1. (a) Chen, J. T.; Thomas, E. L.; Ober, C. K.; Mao, G.-P. Science, 1996, 273, 343. (b) Chen, J. T.; Thomas, E. L.; Ober, C. K.; Hwang, S. S. Macromolecules 1995, 28, 1688. (c) Urbas, A. M.; Thomas, E. L. Adv. Mater. 2002, 14, 1850. (d) Lee, M.-S.; Cho, B.-K.; Zin, W.-C. Chem. Rev. 2001, 101, 3869. (e) Forster, S.; Antonietti, M. Adv. Mater. 1998, 10, 195. (f) Thomas, E. L.; Chen, J. T.; O’Rourke, M. J. E. Macromol. Symp. 1997, 117, 241. (g) Ishizu, K. Prog. Polym. Sci. 1998, 23, 1383. (h) Forster, S.; Plantenberg, T. Angew. Chem. Int. Ed. 2002, 41, 688. (i) Klok, H.-A.; Lecommandoux, S. Adv. Mater. 2001, 13, 1217 2. (a) Baker, W. P. Jr., U.S. Patent 1965, No. 3, 225, 119. (b) Godfrey, R. A.; Miller, G. W. J. Polym. Sci. Part A: Polym. Chem. 1969, 7, 2387 (c) Chen, J. T.; Thomas, E. L.; Ober, C. K.; Mao, G.-P. Science, 1996, 273, 343. (d) Pearce et.al. Macromolecules, 2001, 34, 1828.4. 3. (a) J. –S. Lee, et.al. Journal of Polymer Science: Part A: Polym. Chem. 2005,43, 607. (b) Ahn, J.-H.; Lee, J.-S. Macromol. Rapid Commun. 2003, 24, 571. (c) Ahn, J.-H.; Shin, Y.-D.; Kim, S.-Y.; Lee, J.-S. Polymer. 2003, 44, 3847. (d) Shin, Y.-D.; Han, S.-H.; Samal, S.; Lee, J. –S. Journal of Polymer Science: Part A: Polym. Chem. 2005, 43, 607. 4. Ahn, J.-H., Shin, Y.-D., Nath, G. Y., Park, S.-Y., Rahman, M. S., Samal, S. and Lee, J.-S. J. Am. Chem. Soc. 2005, 127, 4132. |
| 저자 | 라흐만, Samal. S., 이재석 |
| 소속 | 광주과학기술원 |
| 키워드 | Rod-coil; Anionic; Living; Block copolymer |
