title: Two-dimensional Raman correlation spectroscopy reveals molecular structural changes during temperature-induced self-healing in polymers based on the Diels-Alder reaction.
abstract: The thermally healable polymer P(LMA-co-FMA-co-MIMA) has been studied by temperature-dependent FT-Raman spectroscopy, two-dimensional Raman correlation analysis and density functional theory (DFT) calculations. To the best of our knowledge this study reports for the first time on the investigation of a self-healing polymer by means of two-dimensional correlation techniques. The synchronous correlation spectrum reveals that the spectrally overlapping C[double bond, length as m-dash]C stretching vibrations at 1501, 1575, 1585 and 1600 cm(-1) are perfect marker bands to monitor the healing process which is based on a Diels-Alder reaction of furan and maleimide. The comparison between experimental and calculated Raman spectra as well as their correlation spectra showed a good agreement between experiment and theory. The data presented within this study nicely demonstrate that Raman correlation analysis combined with a band assignment based on DFT calculations presents a powerful tool to study the healing process of self-healing polymers.
authors.affiliation: Institute for Physical Chemistry and Abbe Center of Photonics, Friedrich Schiller University Jena, Helmholtzweg 4, 07743, Jena, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Geitner
authors.forename: J
authors.initials: J
authors.lastname: Kötteritzsch
authors.forename: M
authors.initials: M
authors.lastname: Siegmann
authors.forename: T W
authors.initials: TW
authors.lastname: Bocklitz
authors.forename: M D
authors.initials: MD
authors.lastname: Hager
authors.forename: U S
authors.initials: US
authors.lastname: Schubert
authors.forename: S
authors.initials: S
authors.lastname: Gräfe
authors.forename: B
authors.initials: B
authors.lastname: Dietzek
authors.forename: M
authors.initials: M
authors.lastname: Schmitt
authors.forename: J
authors.initials: J
authors.lastname: Popp