Flash Photolysis of Aromatic Diisocyanate-Based Polyurethanes

Authors

Charles E. Hoyle, University of Southern MississippiFollow
Young G. No, University of Southern Mississippi
Keziban S. Ezzell, University of Southern Mississippi

Document Type

Article

Publication Date

12-13-1989

Department

Polymers and High Performance Materials

Abstract

The laser flash photolysis of aromatic diisocyanate based polyurethanes in solution provides evidence for a dual mechanism for photodegradation. One of the processes, an N-C bond cleavage, is common to both TDI (toluene diisocyanate) and MDI (methylene 4,4′-diphenyldiisocyanate) based polyurethanes. The second process, exclusive to MDI based polyurethanes, involves formation of a substituted diphenylmethyl radical. The diphenylmethyl radical, which readily reacts with oxygen, is generated either by direct excitation (248 nm) or indirectly by reaction with a tert-butoxy radical produced upon excitation of tert-butyl peroxide at 351 nm.

Publication Title

ACS Symposium Series

Volume

381

First Page

43

Last Page

56

Recommended Citation

Hoyle, C. E., No, Y. G., Ezzell, K. S. (1989). Flash Photolysis of Aromatic Diisocyanate-Based Polyurethanes. ACS Symposium Series, 381, 43-56.
Available at: https://aquila.usm.edu/fac_pubs/16113