| 학회 | 한국고분자학회 |
| 학술대회 | 2005년 가을 (10/13 ~ 10/14, 제주 ICC) |
| 권호 | 30권 2호 |
| 발표분야 | 탄소나노튜브 및 고분자 복합재료 |
| 제목 | Preparation and Electrospinning of Multiwalled Carbon Nanotube / Polycaprolactone Nanocomposites. |
| 초록 | Multiwalled carbon nanotube/polycaprolactone (MWNT/PCL) nanocomposites were prepared by in-situ polymerization, in which functionalized MWNTs (F-MWNTs), acid treated MWNTs (A-MWNTs) and unfunctionalized MWNTs (P-MWNTs) were used as reinforcing materials. The F-MWNTs were functionalized by Friedel-Crafts acylation [1], which introduce the aromatic amine (COC6H4-NH2) groups on the sidewall, while A-MWNTs were treated with nitric acid [2], which usually attacks the end cap of the MWNT and introduces carboxyl group (COOH). F-MWNT/PCL was chemically bonded with the PCL chains as indicated by appearance of amide II group in FT-IR spectrum. F-MWNT/PCL and A-MWNT/PCL were well dispersed compared to P-MWNT/PCL. The percolation thresholds, which were studied by rheological properties (up-swing of G¢, G² and h* at the low frequency), were found at 2 wt % of MWNT for P-MWNT/PCL and A-MWNT/PCL, although F-MWNT/PCL did not show the percolation threshold up to 7 wt % of MWNT. Disappearance of the percolation threshold of F-MWNT/PCL is attributable to the attached PCL chains on the side wall which blocks the three-dimensional network of MWNT in the nanocomposite. The glass transition temperatures and melting temperatures of the PCL in the nanocomposites did not change with addition of MWNT for P-MWNT/PCL, A-MWNT/PCL and F-MWNT/PCL. The cold crystallization temperatures of P-MWNT/PCL and A-MWNT/PCL increased due to nucleation by the MWNT while F-MWNT/PCL did not give much effect on the cold crystallization temperature. The finer spherulite was observed for P-MWNT/PCL and A-MWNT/PCL although the spherulite of F-MWNT/PCL was similar to that of PCL, which showed big Maltese cross pattern. The difference in the shape of spherulite may be due to the nucleation effects of MWNT for P-MWNT/PCL and A-MWNT/PCL, which coincide with the cold crystallization temperature behavior. The MWNT/PCL nanocomposites containing 0.5–2 wt % MWNTs were also electrospun in a mixture of chloroform and methanol (ratio 3:1) [3], respectively. The diameter of the electrospun fibers ranged between 100 – 250 ± 50 nm. Furthermore, MWNTs in the nanofibers were found to be embedded in the polymer. a b c d Figure 1. SEM micrographs of electrospun nanofibers of (a) PCL, (b) P-MWNT/PCL, (c) A-MWNTs and (d) A-MWNT/ PCL, MWNTs 1 wt %. References: (1) Baek, J. B.; Park, S.Y.; Price, G. E.; Lyons, C.B.;Tan, L. S. Polymer 2005,46, 1543-1552. (2) Hamon, M. A.; Hu, H.; Bhowmik, P.; Niyogi, S.; Zhao, B.; Itkis, M. E.; Haddon, R. C. Chemical Physics Letters 2001,347, 8-12. (3) Dalton, P. D; Klee, D; Moller, M. Polymer 2005, 46,611- 614. |
| 저자 | 칼리드 사이드1, 박수영1, 백종범2 |
| 소속 | 1경북대, 2충북대 |
| 키워드 | PCL; MWNTs; Nanofibers |
