Infrared spectroscopic studies on crystallization and Curie transition behavior of ultrathin films of P(VDF/TrFE) (72/28)

• Published in: Vibrational spectroscopy Vol. 41; no. 1; pp. 1 - 13
• Main Authors: Prabu, A. Anand, Lee, Jong Soon, Kim, Kap Jin, Lee, Han Sup
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 30.05.2006
• Subjects: Crystalline phase; Curie transition; Factor analysis; FTIR spectroscopy; Poly(vinylidenefluoride-co-trifluoroethylene); Ultrathin films; Ultrathin films; Crystalline phase; Poly(vinylidenefluoride-co-trifluoroethylene); Factor analysis; Curie transition; FTIR spectroscopy
• ISSN: 0924-2031; 1873-3697
• DOI: 10.1016/j.vibspec.2005.11.005

The structural phase transition of spin-cast vinylidene fluoride (72 mol%)–trifluoroethylene (28 mol%) random copolymer annealed at different temperatures with varying degree of crystallinity was analyzed qualitatively and quantitatively using Fourier transform infrared transmission (FTIR-TS) and grazing incident reflection absorption (FTIR-GIRAS) spectral data. Using factor analysis of the mixture spectra from samples annealed at different temperatures, we have isolated the pure crystalline and pure amorphous-phase spectra, and the crystalline-phase content was determined quantitatively as a function of annealing temperature. A significant increase in the degree of crystallinity was found for samples annealed at Curie transition range. We have also analyzed the spectra obtained at varying temperatures during a heating–cooling cycle and using factor analysis, the pure spectra of the isolated low-temperature and high-temperature phases were obtained. The low-temperature phase spectra appeared similar to that of the isolated crystalline phase.