Polymerization of HEMA photoinitiated by the Safranine/diphenylborinate system

A new safranin based three-component photoinitiating system for high resolution and low shrinkage printed parts via digital light processing

“…On the other hand, it is well-known that the irradiation of SFH + does not initiate polymerization solely, thus the polymerization process would involve the excitation of the SFH + followed by further reactions. 45 It is worth mentioning that according to the transient absorption spectrum of SFH + , there were three distinct peaks at 430, 520 and 820 nm. The peaks at 430 and 820 nm belong to triplet-triplet absorption of SFH + ( 3 SFH + ) and the peak at 520 nm belongs to SFH + photobleached species.…”

“…Several researchers have reported the radical generation ability of safranin in combination with different coinitiators. [42][43][44][45] Therefore, in this study, a threecomponent PIS based on safranin O was employed in digital light processing 3D printing to investigate the dual function of the dye as photosensitizer and photoabsorber. As mentioned before, the former was responsible for active species production and the latter could play a role in controlling the curing depth and improving the vertical resolution of printed parts.…”

Photochemistry of Tetraphenyldiboroxane and its Use as Photopolymerization Coinitiator,

“…We have previously reported the photooxidation of Safranine (SfH + ) by a neutral arylborane (2‐ethylaminodiphenylborinate, 2APB) used as coinitiator of polymerization . In this system, it was found that there is an electron transfer from the triplet state of dye to the organoborane.…”

Caracterização de copolímeros obtidos via ROMP de monômero derivado do óleo de palma

“…Dentre as técnicas já tradicionalmente exploradas no estudo de polímeros insolúveis, foram exploradas a análise da interação dos polímeros com solventes orgânicos e análises termo-mecânicas. Além destas técnicas, foram exploradas a ressonância magnética nuclear em estado sólido de alta e baixa resolução, úteis ao estudo minucioso da dinâmica molecular de polímeros (DEAZEVEDO et al, 2008;MCBRIERTY;PACKER, 1993;SCHMIDT-ROHR;SPIESS, 1994) assim como para estudos de cinéticas de polimerização.…”

“…O uso da FT converte o resultado obtido em função do tempo para outro no domínio das frequências, o que permite a análise detalhada de um mistura complexa de sinais. Quando se trabalha com análise de compostos no estado sólido, principalmente sólidos amorfos ou semicristalinos, uma série de interações entre os núcleos analisados se manifesta e prejudica a resolução dos espectros obtidos (DUER, 2004;MCBRIERTY;PACKER, 1993;SCHMIDT-ROHR;SPIESS, 1994).…”