| 학회 | 한국고분자학회 |
| 학술대회 | 2005년 가을 (10/13 ~ 10/14, 제주 ICC) |
| 권호 | 30권 2호 |
| 발표분야 | 고분자 합성 |
| 제목 | PERFECT CONTROL OVER POLYMERIZATION OF n-HEXYL ISOCYANATE USING A NOVEL INITIATOR THAT COMBINES INITIATION WITH CHAIN-END PROTECTION |
| 초록 | Polyisocyanates and its copolymers are fascinating materials because of their broad-ranging applications such as, optical switching, liquid crystals, degradable materials, composites, chiral recognition, and inorganic nanoparticles [1]. For most of these applications it is desirable that the molecular weight (MW) and the molecular weight distribution (MWD) of the polymer be controlled and defined. The living anionic polymerization of isocyanates carried out using conventional initiators is associated with side reactions due to rapid initiation rates as well as backbiting by the growing chain. That results in a lack of control over the MW and MWD of the polymers. Successful control over the polymerization was possible by using additives such as 15-crown-5 and sodium tetraphenylborate that could prevent backbiting [2,3]. To find newer and more effective initiators, we carried out the polymerization of n-hexyl isocyanate (HIC) using sodium naphthalenide (Na-Naph), sodium diphenylmethane (Na-DPM), and sodium benzanilide (Na-BA). Interestingly, we find that Na-BA is an unique initiator for the polymerization of isocyanates since it serves the dual function of controlled initiation and efficient protection of the living chain-ends (Scheme 1), resulted polymers in ~ 100% yield [4]. References [1] (a) Mayer, S.; Zentel, R. Prog. Polym. Sci. 2001, 26, 1973. (b) Han, S. H.; Kang, J.-W.; Shin, Y.-D.; Lee, J.-S.; Kim, J.-J.; Wu, J. W. J. Opt. Soc. Am. B 2001, 18, 298. (c) Cho, Y.-H.; Cho, G.; Lee, J.-S. Adv. Mater. 2004, 16, 1814. (d) Shin, Y.-D., Han, S.-H.; Samal, S.; Lee, J.-S. J. Polym. Sci.- Polym. Chem. Ed. 2005, 43, 607. [2] (a) Lee, J.-S.; Ryu, S.-W. Macromolecules 1999, 32, 2085. (b) Shin, Y.-D.; Ahn, J.-H.; Lee, J.-S. Polymer 2001, 424, 7979. [3] (a) Shin, Y.-D.; Kim, S.-Y.; Ahn, J.-H.; Lee, J.-S. Macromolecules 2001, 34, 2408. (b) Ahn, J.-H.; Lee, J.-S. Macromol. Rapid Commun. 2003, 24, 571. (c) Ahn, J.-H.; Lee, C.-H.; Shin, Y.-D.; Lee, J.-S. J. Polym. Sci.-Polym. Chem. Ed. 2004, 42, 933. [4] Ahn, J.-H.; Shin, Y.-D.; Yogendra Nath G.; Park, S.-Y.; Rahman, M. S.; Samal, S.; Lee, J.-S. J. Am. Chem. Soc. 2005, 127, 4132. |
| 저자 | 이재석 |
| 소속 | 광주과학기술원 |
| 키워드 | Anionic polymerization; Living; Polymers |
