Flash Photolysis of Aromatic Diisocyanate Based Polyurethanes.
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 by reaction with a tert-butoxy radical produced upon excitation of tert-butyl peroxide at 351 nm.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 10, 1988
- Accession Number
- ADA192278
Entities
People
- C. E. Hoyle
- Y. G. No
Organizations
- University of Southern Mississippi