Efficient photoacids based upon triarylamine dialkylsulfonium salts
Wenhui Zhou1, Stephen M Kuebler, Dave Carrig
1Department of Chemistry, University of Arizona, Tucson, Arizona 85721, USA.
Journal of the American Chemical Society
|February 28, 2002
Summary
New photoacid generating compounds, triarylamine dialkylsulfonium salts, show high efficiency in photopolymerization. Their performance in initiating cationic polymerization depends on specific salt structures and counterions.
Area of Science:
- Organic Chemistry
- Polymer Science
- Photochemistry
Background:
- Triarylamine compounds are known for their electronic properties.
- Sulfonium salts are utilized in various chemical applications.
- Photoacid generators are crucial for photolithography and photopolymerization.
Purpose of the Study:
- To synthesize and characterize novel triarylamine dialkylsulfonium salts.
- To investigate their photosensitivity in the near-UV range.
- To evaluate their efficiency as cationic photoinitiators for photopolymerization.
Main Methods:
- Synthesis of triarylamine dialkylsulfonium salts.
- Measurement of quantum yields for photoacid generation.
- Photopolymerization studies of cyclohexene oxide.
- Kinetic analysis of photopolymerization reactions.
Main Results:
- New photosensitive triarylamine dialkylsulfonium salts were successfully prepared.
- Quantum yields for photoacid generation were consistently around 0.5, irrespective of the counterion.
- The efficiency of photopolymerization was influenced by the counterion and sulfonium substituents.
- Triphenylamine sulfonium salts demonstrated high efficiency as cationic photoinitiators.
Conclusions:
- The synthesized sulfonium salts are effective photoacid generators.
- Their utility as cationic photoinitiators is confirmed, with performance modulated by structural variations.
- These findings contribute to the development of advanced photoinitiator systems.
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