Dibenzophenazine and quinoxaline derivatives as novel visible photosensitizers for diaryliodonium salts

Kolay, Merve
This study is focused on the use of visible light in photoinitiated cationic polymerization. Photoinitiated polymerization of oxiranes, vinyl ethers, and other vinyl monomers was achieved. In doing so, (2-(2,3 dihydrobenzo [b][1,4]dioxin-6-yl)-3-(2,3-dihydrobenzo[b]-[1,4]dioxin-7-yl)-5-(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-8-(2,3-dihydrothieno[3,4-b][1,4]dioxin-7yl) quinoxaline) (DBQEd) and poly(2,3,5,8-tetra(thiophen-2-yl)quinoxaline) (TTQ), two dibenzo[a,c]phenazine derivatives; 10,13-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)dibenzo[a,c] phenazine (PHED) and 10,13-bis(4-hexylthiophen-2-yl)dibenzo[a,c]phenazine (PHEHT) were utilized as the photosensitizers for diaryliodonium salt photoinitiators. Novel dyes based on the dibenzo[a,c]phenazine and quinoxaline skeleton were shown to be efficient in carrying out the cationic photopolymerizations of a wide variety of epoxide, oxetane, and vinyl monomers at room temperature upon irradiation with long-wavelength UV and visible light. The polymerizations were initiated at room temperature in the presence of diphenyliodonium hexafluorophosphate (Ph2I+PF-6) and monitored by optical pyrometry (OP). The photopolymerization of an epoxide monomer via solar irradiation was also demonstrated.


Pion electroproduction in parity violating elastic ep scattering experiment
Ong, S; Rekalo, MP; Van de Wiele, J (Springer Science and Business Media LLC, 1999-10-01)
This study has been developed for electron-proton scattering experiments when only the scattered electrons are detected. Pion electroproduction on the proton including the cascade pi(o) --> 2 gamma decay and the QED radiative corrections to elastic ep scattering are investigated. Our results are shown in the kinematical configuration of the parity violating electron scattering experiment planned at the Mainz Microtron (MAMI).
Digestion of animal- and plant-based proteins encapsulated in kappa-carrageenan/protein beads under simulated gastrointestinal conditions
Özel, Barış; He, Lili; McClements, David Julian (Elsevier BV, 2020-11-01)
In this study, we encapsulated both animal-derived (whey) and plant-derived (soy and pea) proteins within polysaccharide/protein beads and measured the digestion of these beads under simulated gastrointestinal tract (GIT) conditions. Bead dimensions were measured using a digital caliper and found to increase as the shear thinning behavior of the protein/polysaccharide solutions used to form them increased. The hydrolysis of the plant and animal proteins trapped inside the protein/polysaccharide beads was st...
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The aim of this study was to determine the rheological properties of tahin/pekmez blends at different tahin concentrations (20-32%) and temperatures (35-65 C) by using a concentric cylinder rotational viscometer. Samples were sheared with seven different rotational speeds at an increasing order. The shear rates (0.75-63.9 s-1) were calculated by the Power-law Approximation method. Tahin/pekmez blends were found to exhibit non-Newtonian, shear thinning behavior at all temperatures and tahin concentrations. T...
Cinnamon oil nanoemulsions by spontaneous emulsification: Formulation, characterization and antimicrobial activity
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The goal of this study was to formulate stable cinnamon oil nanoemulsions (NEs) exhibiting high anti-microbial activity by using the low-energy approach: spontaneous emulsification (SE) and compare it with two high-energy methods. To prepare the nanoemulsions by SE, oil phase containing cinnamon oil (CO) and carrier oil (coconut oil (CNO)) at different ratios (2:8-10:0) and surfactant (Tween 80) at 10% (w/w) was titrated into an aqueous phase (distilled water). For antimicrobial activity, agar disc diffusio...
Yalcin, Engin; YILMAZ, ASIM EGEMEN; Kuzuoğlu, Mustafa (World Scientific Pub Co Pte Lt, 2013-08-01)
In this study, by means of parametric distortion of an ideal hexahedral element, we investigate the accuracy and sensitivity of some hexahedral element quality metrics existing in the literature. We also investigate and compare the relative computational costs of each metrics. We try to identify the weaknesses and strengths of all metrics under interrogation, and come up with some proposals for practical use.
Citation Formats
M. Kolay, “Dibenzophenazine and quinoxaline derivatives as novel visible photosensitizers for diaryliodonium salts,” M.S. - Master of Science, Middle East Technical University, 2011.