Abstract

There are no reports on the stability of autofluorescence, although lignins and their solutions are known to exhibit autofluorescence. An aim of this study is to investigate spectral change of lignin autofluorescence under prolonged excitation with ultraviolet (UV). Both fluorescence spectra of softwood milled wood lignin (MWL) and kraft lignin (SKL) in propylene glycol significantly changed upon an UV irradiation at 280 nm under O2 and Ar atmospheres even for 10 min. By the further irradiation, the autofluorescence intensities were remarkably changed together with the emission wavelengths. However, no tendency in the autofluorescence change was observed. The change varied between lignin preparations and gas atmosphere. These phenomena should be caused by autoxidation upon UV irradiation, and the reaction resulted in not only photodegradation but also photopolymerization.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.