Three-component photo radical initiating system—the effect of 2-mercaptobenzothiazole as a co-initiator in polymer matrix

Suzuki, Shota; Emilie, Perrier; Urano, Toshiyuki; Takahara, Shiro; Yamaoka, Tsuguo

doi:10.1016/j.polymer.2005.01.039

Cited by 36 publications

(35 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…[1][2][3][4][5][6][7][8][9][10] The ability of a series of new thiols RSH and disulfides RS-SR to generate RS and initiate a radical polymerization process was recently examined. [11] It was demonstrated that some of these structures can lead to powerful initiating species, [11] better than the compounds mentioned today in the Radiation Curing and Laser Imaging areas.…”

Section: Introductionmentioning

confidence: 99%

Thiyl Radical Generation in Thiol or Disulfide Containing Photosensitive Systems

Lalevée

Morlet‐Savary

Roz

et al. 2009

Macro Chemistry & Physics

View full text Add to dashboard Cite

The generation of thiyl radicals in various multicomponent photosensitive systems based on a ketone, a coumarin or a ketocoumarin and containing a thiol or a disulfide and eventually chloro bis‐imidazole has been studied through laser flash photolysis. A set of more than 70 new interaction rate constants is provided. The measurements of the quantum yields in sulfur radicals and the rate constants of the different processes in many combinations as well as the molecular orbital calculations allow to discuss the driving factors of the involved reactions. This approach should shed some light on the possible explanations of the high performance of some of these combinations when used as photoinitiating systems for radical photopolymerization reactions.magnified image

show abstract

Section: Introductionmentioning

confidence: 99%

Thiyl Radical Generation in Thiol or Disulfide Containing Photosensitive Systems

Lalevée

Morlet‐Savary

Roz

et al. 2009

Macro Chemistry & Physics

View full text Add to dashboard Cite

show abstract

“…Aromatic thiols are well-known strong quenchers of the triplet state photoinitiators. [51][52][53][54] Investigating the initiation mechanism by laser flash photolysis, Andrzejewska and co-workers observed a rapid quenching of the excited ITX * with the thiols as the transient peak of ITX * around 640 nm dropped quickly following the appearance of new absorption peaks at 425 and 590 nm. The observed insensitivity of thiol-based systems to oxygen inhibition is due to the ability of peroxy radicals formed by oxygen scavenging to abstract a hydrogen atom from the thiols thus giving rise to the formation of a new initiating thiyl radical.…”

Section: Co-initiatorsmentioning

confidence: 99%

Shining a light on an adaptable photoinitiator: advances in photopolymerizations initiated by thioxanthones

2015

View full text Add to dashboard Cite

Photochemistry has been playing a central role in the synthetic polymer community. Aromatic ketones, examples of which include benzophenone, thioxanthone, camphorquinone, among others, are renowned for their excellent optical characteristics and have been extensively taken advantage of photochemically induction of polymerization processes. Of particular interest is thioxanthone due to its adaptability for bearing different functionalities and applications in various modes of photopolymerization which accomplishes photoinitiation in conjunction with other co-initiator compounds; a behavior that is referred to as bi-molecular photoinitiation. In this paper, we review the photochemistry of thioxanthonebased systems and their use in different modes of photoinitiated polymerizations. Citing examples from literature, the development of various photoinitiating systems based on thioxanthones along with an understanding of their mechanistic behavior has been elucidated in advance.Scheme 1 Typical representation of the photolysis of the radical photoinitiators based on Type I (top) and Type II (bottom) systems on the example of a benzoin derivative and thioxanthone, respectively.Scheme 3 Synthesis of thioxanthones by condensation of thiosalicylic acid and aromatic compounds in the presence of concentrated sulfuric acid.

show abstract

“…Visible light is also cheaper and safer, and it possesses higher penetration in comparison with UV light. To eliminate UV radiation, the typical type II photoinitiators are being replaced with organic dyes that are sensitive to visible light .…”

Section: Introductionmentioning

confidence: 99%

“…The structures of the dyes and the hydrogen donors employed in this study are shown in Schemes 1 and 2 respectively. In the present experiments, 2‐mercaptobenzoxazole ( D1 ), 2‐mercaptobenzothiazole ( D2 ), 2‐mercaptobenzimidazole ( D3 ) and 2,5‐dimercapto‐1,3,4‐thiadiazole ( D4 ) were chosen because they act as effective hydrogen donors with activities comparable to those of aromatic amines .…”

Section: Introductionmentioning

confidence: 99%

Dyes based on a 1,4‐naphthoquinone skeleton as new type II photoinitiators for radical polymerisation

Szymczak

Podemska

Sokołowska

2013

Coloration Technology

View full text Add to dashboard Cite

Photoredox pairs consisting of 1,4‐naphthoquinone dyes and commercially available hydrogen donors (2‐mercaptobenzoxazole, 2‐mercaptobenzothiazole, 2‐mercaptobenzimidazole and 2,5‐dimercapto‐1,3,4‐thiadiazole) are found to be effective initiator systems for the radical polymerisation of trimethylolpropane triacrylate under visible light. The efficiency of these initiator systems is discussed in terms of the free energy change for the electron transfer process from the dye to the hydrogen donor. The results show that the photoinitiation ability of tested photoredox pairs depends on the structure of both the dye and the hydrogen donor.

show abstract

Three-component photo radical initiating system—the effect of 2-mercaptobenzothiazole as a co-initiator in polymer matrix

Cited by 36 publications

References 19 publications

Thiyl Radical Generation in Thiol or Disulfide Containing Photosensitive Systems

Thiyl Radical Generation in Thiol or Disulfide Containing Photosensitive Systems

Shining a light on an adaptable photoinitiator: advances in photopolymerizations initiated by thioxanthones

Dyes based on a 1,4‐naphthoquinone skeleton as new type II photoinitiators for radical polymerisation

Contact Info

Product

Resources

About