UV-induced electrical and optical changes in PVC blends

Date
2001
Advisor
Instructor
Source Title
Monatshefte fur Chemie
Print ISSN
0026-9247
Electronic ISSN
Publisher
Springer
Volume
132
Issue
1
Pages
185 - 192
Language
English
Type
Article
Journal Title
Journal ISSN
Volume Title
Abstract

2-Chloro-polyaniline (2-Cl-PANI) in its non-conducting (emeraldine base, EB) form, prepared by a chemical route, was dissolved together with poly-(vinylchloride) (PVC) in THF for casting into thin (10-50 μm) films. Upon exposure to UV radiation, the electrical conductivity of these films increased by more than 4 orders of magnitude (from 10-6 to 10-2 S/cm). This is attributed to the dehydrochlorination of PVC by exposure to energetic photons and subsequent doping of 2-Cl-PANI (i.e. conversion to emeraldine salt, ES) by in situ created HCl. The doped films could be returned to their undoped form by exposure to NH3 vapours. The UV-induced doping/NH3 undoping cycles could be repeated several times. Various spectroscopic techniques were employed to follow the changes in the films upon exposure to UV radiation. The same photo-dehydrochlorination process has also been utilized for optical and/or lithographic purposes by preparing PVC blends containing methyl violet, and acid-base indicator dye. The photo-dehydrochlorination can be effectively sensitized by incorporating hydroquinone into the PVC blends containing methyl violet.

Course
Other identifiers
Book Title
Keywords
2 - chloro - polyaniline, Dehydrochlorination of PVC, Optical litography, Photochemical sensitization, Photochemistry
Citation
Published Version (Please cite this version)