๐”– Bobbio Scriptorium
โœฆ   LIBER   โœฆ

Photochemistry and photopolymerization activity of novel 4-alkylamino benzophenone initiators-synthesis, characterization, spectroscopic and photopolymerization activity

โœ Scribed by Norman S. Allen; Edward Lam; Edward M. Howells; Peter N. Green; Arthur Green; Fernando Catalina; Carmen Peinado


Publisher
Elsevier Science
Year
1990
Tongue
English
Weight
679 KB
Volume
26
Category
Article
ISSN
0014-3057

No coin nor oath required. For personal study only.

โœฆ Synopsis


Fifteen novel 4-substituted alkylaminobenzophenones have been synthesized and characterized using NMR, mass spectrometry and microanalysis. Their spectroscopic properties have been determined using u.v. absorption and phosphorescence analysis and the data related to their behaviour on photocuring using both Fourier Transform Infra-Red (FTIR) analysis and hardness testing in a triacrylate monomer. Absorption and phosphorescence spectra are similar to those of benzophenone although the quantum yields are lower with longer emission lifetimes indicative of the presence of some degree of charge-transfer in the lowest excited triplet state. Using FTIR analysis for photocuring, the compounds are in many cases more effective than benzophenone itself. Using hardness testing on the other hand, all the compounds proved to be more effective; the alicyclic amine structures are the least effective followed by the aliphatic and then the aromatic amines. For structural analogues, photocuring was more effective for those containing a propoxy link in the substituent than for those containing an ethoxy link. This difference is related to the ability of the molecule in the former case to form an intra-molecular exciplex with the aromatic ketone group. The alicyclic compounds are less effective in hydrogen atom or electron abstraction reactions. Differences observed in the methods of curing are related to the quenching effects of oxygen


๐Ÿ“œ SIMILAR VOLUMES


Photochemistry and photopolymerization a
โœ N.S. Allen; S.J. Hardy; A. Jacobine; D.M. Glaser; F. Catalina ๐Ÿ“‚ Article ๐Ÿ“… 1989 ๐Ÿ› Elsevier Science ๐ŸŒ English โš– 525 KB

The photochemistry and photopolymerization activity of three novel t-butylperester derivatives of fluorenone have been examined and compared with unsubstituted fluorenone and a tetra-t-butylperester of benzophenone. The longest wavelength absorption bands of all three derivatives are blue-shifted fr

Photochemistry and photopolymerization a
โœ Norman S. Allen; Deborah Mallon; Irini Sideridou; Arthur Green; Alan Timms; Fern ๐Ÿ“‚ Article ๐Ÿ“… 1992 ๐Ÿ› Elsevier Science ๐ŸŒ English โš– 318 KB

A~tract--The photochemistry and photopolymerization activity of a novel initiator, 3,4-dimethyl-2-(3-N,N-dimethyl)-n-propoxythioxanthone, has been compared with that of the non-aminated molecule, 3,4-dimethyl-2-n-propoxythioxanthone. Using photodilatometry, the rate of photopolymerization of n-butyl

Synthesis and spectroscopic properties o
โœ Norman S. Allen; Deborah Mallon; Alan Timms; Arthur W. Green; Fernando Catalina ๐Ÿ“‚ Article ๐Ÿ“… 1993 ๐Ÿ› Elsevier Science ๐ŸŒ English โš– 498 KB

Al~traet--Eight novel mono and bis-para-substituted derivatives of benzophenone containing cinnamate and cinnamamide groups are synthesized and characterized. The spectroscopic properties of these new photoinitiators are examined, related to their photucuring behaviour in an epoxy acrylate resin and