Quinoxaline derivatives as long wavelength photosensitizers in photoinitiated cationic polymerization of diaryliodonium salts

Bulut, Umut
Kolay, Merve
Tarkuc, Simge
Udum, Yasemin Arslan
Toppare, Levent Kamil
The present paper is focused on visible light initiated cationic polymerizations. Photoinitiated polymerization of representative vinyl ether and oxirane monomers using two quinoxaline derivatives; namely (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 2,3,5,8-tetra(thiophen-2-yl)quinoxaline (TTQ) are studied. Novel dyes based on the quinoxaline skeleton are employed as efficient photosensitizers in cationic photopolymerizations. Polymerizations were initiated at room temperature upon irradiation with long-wavelength UV and visible lights in the presence of diphenyliodonium hexafluorophosphate (Ph(2)1(+)PF(6)(-)). The progress of the polymerizations was monitored by optical pyrometry (OP). Solar irradiation is also employed to carry out the cationic polymerization of a diepoxide monomer in the presence of air.


Dibenzophenazine and quinoxaline derivatives as novel visible photosensitizers for diaryliodonium salts
Kolay, Merve; Toppare, Levent Kamil; Bulut, Umut; Department of Chemistry (2011)
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-dihydro...
Optically stimulated luminescence studies on natural fluorites
Kuşoğlu Sarıkaya, Cemre; Bulur, Enver; Department of Physics (2011)
Optically Stimulated Luminescence (OSL) is the luminescence emitted from a previously irradiated insulator (or a wide band gap semiconductor) upon exposure to light. The OSL signal intensity is a function of the radiation dose absorbed by the sample and thus can be used as the basis of a radiation dosimetry method. In the literature, OSL studies on natural fluorites are rather limited. In order to promote the material for radiation dosimetry, OSL properties of natural fluorites of different origin were exam...
Donor-acceptor type random copolymers for full visible light absorption
Oktem, Gozde; Balan, Abidin; Baran, Derya; Toppare, Levent Kamil (Royal Society of Chemistry (RSC), 2011-01-01)
Copolymerization towards obtaining full visible light absorption is highlighted. Randomly distributed segments of different oligomers resulted in neutral state black copolymers. Solution processability and highly transmissive gray oxidized states make copolymers great candidates to be used in low cost flexible organic electronics.
Modeling of inelastic behavior of curved members with a mixed formulation beam element
Sarıtaş, Afşin (Elsevier BV, 2009-04-01)
The curved beam element in this paper is based on Hu-Washizu variational principle. The nonlinear response of the element arises from the integration of stress-strain relations over several control sections along the element length. The finite element approximation for the beam uses shape functions for stress resultants that satisfy equilibrium and discontinuous strains along the beam. No approximation for the beam displacement field is necessary in the formulation. The proposed element is free from membran...
Highly Conjugated Thiophene Derivatives as New Visible Light Sensitive Photoinitiators for Cationic Polymerization
Aydogan, Binnur; Günbaş, Emrullah Görkem; Durmus, Asuman; Toppare, Levent Kamil; Yağcı, Yusuf (2010-01-12)
A visible light sensitive photoinitiator system for the cationic polymerization of typical monomers, e.g. of oxiranes such as cyclohexene oxide, of vinyl ethers such as n-butyl vinyl ether, and of other vinyl monomers such its N-vinylcarbazole, using highly conjugated thiophene derivatives is described. The cationic polymerization of these monomers was initiated at room temperature upon irradiation in the visible region (lambda(inc) = 480 nm) in CH2Cl2 solutions with 4,7-di(2,3-dihydrothieno[3,4-b][1,4]diox...
Citation Formats
U. Bulut, M. Kolay, S. Tarkuc, Y. A. Udum, and L. K. Toppare, “Quinoxaline derivatives as long wavelength photosensitizers in photoinitiated cationic polymerization of diaryliodonium salts,” PROGRESS IN ORGANIC COATINGS, pp. 215–218, 2012, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/39939.