| 학회 | 한국고분자학회 |
| 학술대회 | 2005년 봄 (04/14 ~ 04/15, 전경련회관) |
| 권호 | 30권 1호, p.528 |
| 발표분야 | 고분자 구조 및 물성 |
| 제목 | Studies on the ethylene glycol degradation mechanism of nylon 6,6 using a model compound N,N-hexamethylenebishexamide (HMHA) |
| 초록 | Nylon 6,6 is an important material used in high performance molded applications, tire cords, and various types of automobile parts1,2. The objective of our work is to study degradation mechanism of nylon 6,63 by ethylene glycol (EG) using a model compound N,N-hexamethylenebishexamide (HMHA). HMHA was prepared by reacting hexanoic anhydride with hexamethylenediamine in dimethylformamide solution at 40oC for 2 hrs and the product was characterized by FT-IR, NMR, and GC-MS. Glycolysis reaction was carried out using 1:5 mol ratio of HMHA:EG in an autoclave at 250oC for 16.5 h. The glycolyzed samples were collected at various intervals of time and characterized using FT-IR and GC-MS. From FT-IR, the broad band around 3500-3000 cm-1 indicates the presence of secondary amide, primary amine, and primary alcohol. However, the amount of the primary amine formed is too low to be distinguished from the secondary amide peak as shown in Fig. 1(a) because of low equilibrium constant. The sharp peak at 3307 cm-1 is seen clearly during glycolysis which may be due to the presence of asymmetric vibration of primary amine formed and the reduction of hydroxyl groups through glycolysis reaction. The increase of ester band at 1734 cm-1 and reduction of amide band at 1632 cm-1 can be seen in Figs. 1(b) and 1(c). From Fig. 1(c), there is no significant increase in the ester band after 11 hours, which indicates that the glycolysis reaction may reach an equilibrium state. GC-MS analysis was carried out for the sample collected at 6 hrs. GC-MS data reveal the formation of an ester (β-hydroxyethylhexanoate) and also indicate the presence of unreacted HMHA during glycolysis reaction, which corroborates with FT-IR data that the glycolysis reaction is an equilibrium reaction. Hence the mechanism for degradation of model compound by ethylene glycol is derived on the basis of FT-IR and GC-MS data as shown in Scheme 1. Figure 1. FT-IR spectra for glycolyzed HMHA in the range of (a) 4000-2000 cm-1, (b) 2000-600 cm-1 and (c) changes in A1734/A1632 (ester/amide) as a function of glycolysis time. Scheme 1: Glycolysis of model compound (HMHA) References: 1. M.I. Kohan, Nylon plastics handbook. New York: Hanser/Gardner, 1995. 2. P.L. Lann, T.S. Derevjanik, J.W. Snyder, W.C. Ward Jr., Thermochimica Acta, 357, 225 (2000). 3. B. Hommez and E.J. Goethals, JMSPAC, A35(9), 1489 (1998). Acknowledgement: One of the authors(KJK) greatly appreciates financial support from Hyundai Motor Company. |
| 저자 | D. Manjula Dhevi1, 이종순1, 조영달2, 최은경2, 김갑진1 |
| 소속 | 1경희대, 2한국생산기술천안(연) |
| 키워드 | Ethylene glycol; degradation; nylon 66; N; N-hexamethylenebishexamide |
