화학공학소재연구정보센터
Macromolecular Research, Vol.11, No.5, 297-302, October, 2003
Effect of Thermal Imidization and Curing on Fluorescence Behavior of a Phenylethynyl-Terminated Poly(amic acid)
E-mail:
The imidization and cure reaction of a thermosetting phenylethynyl-terminated amic acid (LaRC PETI-5) in film form have been monitored as a function of temperature by means of a steady-state fluorescence technique using a front-face illumination method. The variation of the fluorescence emission spectra of LaRC PETI-5 can be divided into four temperature regions; Region I: below 150oC, Region II: 150-250 ℃, Region III: 250-350 ℃, and Region IV: above 350 ℃. The fluorescence spectra in Region I are largely influenced by residual N-methyl-2-pyrrolidinone in the polymer and also slightly by partial imidization of the polymer. There is a combined effect of imidization and solvent removal on the fluorescence behavior in Region II. The spectra in Regions III and IV are due significantly to the cure reaction of LaRC PETI-5 and to a post-cure effect of the polyimide, respectively. This spectroscopic evidence indicating the transformation of the amic acid imide oligomer into the corresponding polyimide via imidization and cure, agrees well with thermal analysis results obtained previously. The intermediate stage of cure in the range of 250-300 ℃ predominantly influences the change of the fluorescence intensity. The later stage above 300 ℃ significantly influences the position of the spectrum. This fluorescence study also supports the mechanism proposed in earlier work that the crosslinking reaction takes place at the reaction sites in the conjugated polyene and the phenylethynyl end group in the polyimide chain.
  1. Hergenrother PM, Smith JG, Polymer, 35(22), 4857 (1994) 
  2. Jensen BJ, Bryant RG, Smith JG, Hergenrother PM, J. Adhes., 54, 57 (1995)
  3. Hergenrother PM, SAMPE J., 35(1), 30 (1999)
  4. Connell JW, Smith JG, Hergenrother PM, J. Macromol. Sci.-Rev. Macromol. Chem. Phys., C40, 207 (2000)
  5. Rommel ML, Konopka L, Hergenrother PM, 28th Intl SAMPE Technical Conference, Nov. 4-7, 1 (1996)
  6. Cho DW, Choi YS, Drzal LT, Polymer, 42(10), 4611 (2001) 
  7. Fang XM, Rogers DF, Scola DA, Stevens MP, J. Polym. Sci. A: Polym. Chem., 36(3), 461 (1998) 
  8. Chang AC, Jensen BJ, J. Adhes., 72, 209 (2000)
  9. Hinkley JA, Proctor DA, J. Adv. Mater., 32(4), 35 (2000)
  10. Wachsman ED, Frank CW, Polymer, 29, 1191 (1988) 
  11. Lin KF, Wang FW, Polymer, 35(4), 687 (1994) 
  12. Cho D, Kim DS, Lee JK, Polym.(Korea), 25(2), 199 (2001)
  13. Mathisen RJ, Yoo JK, Sung CSP, Macromolecules, 20, 1414 (1987) 
  14. Pyo SM, Shin TJ, Kim SI, Ree M, Mol. Cryst. Liq. Cryst., 316, 353 (1998)
  15. Jessop JL, Scranton AB, Blanchard GJ, Polym. Mater. Sci. Eng., 72, 58 (1995)
  16. Vatanparast R, Li SY, Hakala K, Lemmetyinen H, Macromolecules, 33(2), 438 (2000) 
  17. Stroeks A, Shmorhun M, Jamieson AM, Simha R, Polymer, 29, 467 (1988) 
  18. Cho D, Choi Y, Drzal LT, J. Adhes., 79, 1 (2003) 
  19. Cho D, Yang G, Drzal LT, Polym. Mater. Sci. Eng., 87, 283 (2002)
  20. Shin TJ, Lee B, Youn HS, Lee KB, Ree M, Langmuir, 17(25), 7842 (2001) 
  21. Cho DH, Drzal LT, J. Appl. Polym. Sci., 75(10), 1278 (2000) 
  22. Cho DW, Drzal LT, J. Appl. Polym. Sci., 76(2), 190 (2000) 
  23. Hasegawa M, Arai H, Mita I, Yokota R, Polym. J., 22, 875 (1990) 
  24. Hasegawa M, Horie K, Prog. Polym. Sci., 26, 259 (2001) 
  25. Hasegawa M, Kochi M, Mita I, Yokota R, Eur. Polym. J., 25, 349 (1989)