Article
Polymer Science
Zhong-Han Lee, Fatima Hammoud, Akram Hijazi, Bernadette Graff, Jacques Lalevee, Yung-Chung Chen
Summary: Four visible light triphenylamine-based oxime ester photoinitiators were successfully synthesized and confirmed through various measurements. These photoinitiators showed good double bond conversion efficiency in free radical polymerization. The photochemical reaction behavior was studied using various techniques such as photolysis, cyclic voltammograms, electron spin resonance, and theoretical calculations.
Article
Polymer Science
Fatima Hammoud, Akram Hijazi, Sylvain Duval, Jacques Lalevee, Frederic Dumur
Summary: The article presents a series of compounds based on the 5,12-dihydroindolo[3,2-a]carbazole scaffold, where selective introduction of different functional groups on the two carbazole moieties was achieved by controlling reaction conditions. Experimental evidence showed higher reactivity of one of the carbazoles, leading to the generation of asymmetrically substituted structures.
EUROPEAN POLYMER JOURNAL
(2022)
Article
Polymer Science
Filip Petko, Mariusz Galek, Emilia Hola, Roman Popielarz, Joanna Ortyl
Summary: This paper presents a novel method for synthesizing benzylidene iodonium salts as photoinitiators and investigates their properties, showing efficient decomposition under UV to visible light and potential application in 3D printing.
Article
Polymer Science
Alicja Balcerak, Dominika Kwiatkowska, Janina Kabatc
Summary: This study explores the efficiency of novel two-component photoinitiators based on a typical squaraine dye and its difluoroborate analogues for the radical polymerization of acrylate monomers. The synthesized dyes combined with various co-initiators showed different photoinitiation abilities for visible-light photoinitiating systems. The results suggest that the proposed systems are dependent on the structure of both sensitizer and co-initiator, as well as the concentration of applied photoinitiator.
Article
Polymer Science
Mahmoud Rahal, Guillaume Noirbent, Bernadette Graff, Joumana Toufaily, Tayssir Hamieh, Didier Gigmes, Frederic Dumur, Jacques Lalevee
Summary: This study focuses on the investigation of two new copper complexes as visible light photoinitiators for free radical photopolymerization of acrylates, showing promising results in combination with iodonium salts and/or amines in multi-component photoinitiating systems.
Article
Polymer Science
Timur Borjigin, Guillaume Noirbent, Didier Gigmes, Pu Xiao, Frederic Dumur, Jacques Lalevee
Summary: In this study, a ligand and four copper complexes were found to exhibit excellent photosensitivity in various photoinitiating systems, particularly in the free radical polymerization and cationic polymerization processes. By investigating the performance of different photoinitiating systems, better support for 3D printing experiments was achieved.
EUROPEAN POLYMER JOURNAL
(2022)
Article
Chemistry, Physical
Ali Suerkan, Recep Isci, Turan Ozturk, Yusuf Yagci
Summary: A donor-acceptor type photoinitiator, DMB-TT-TPA, composed of boron-thienothiophene-triphenylamine, was studied for cationic and radical polymerization. Mono and difunctional monomers were irradiated under a white LED source in the presence of DMB-TT-TPA and DPI. The initiation process was investigated using fluorescence spectroscopy, and the presence of the synthesizer in the polymer structures was confirmed by NMR spectroscopy studies. This study demonstrated the importance of the photoinduced electron transfer process in the initiation of polymerization and the formation of conjugated polymers.
MOLECULAR SYSTEMS DESIGN & ENGINEERING
(2023)
Review
Polymer Science
Frederic Dumur
Summary: Visible light photopolymerization has gained renewed interest due to its application in 3D printing. New structures disconnected from traditional photoinitiators are being widely examined for developing visible light photoinitiating systems. The parameters such as excited state lifetimes, redox properties, and molar extinction coefficients of newly prepared photoinitiators need to be considered for efficient interaction with additives in photocurable resins. Thiophene, widely used in Organic Electronics, is a potential candidate for visible light photoinitiators due to its low oxidation potential and easy chemical modification. Different types of thiophene-based photoinitiators have been developed over the years. This review provides an overview of recent advances in thiophene-based photoinitiators and compares them with reference photoinitiating systems to highlight their significance.
EUROPEAN POLYMER JOURNAL
(2022)
Article
Polymer Science
Frederic Dumur
Summary: Photopolymerization is currently a focused area of research due to the need for visible light-activated photoinitiating systems. Pyrrole has been identified as an interesting scaffold for designing various dyes and developing new formulations with fast polymerization kinetics, high monomer conversions, low energy consumption, and activation in the visible range.
EUROPEAN POLYMER JOURNAL
(2022)
Article
Polymer Science
Frederic Dumur
Summary: This review provides an overview of the recent developments concerning phenothiazine-based photoinitiators of polymerization, highlighting the evolution and structural changes of these molecules within photoinitiators. By comparing with reference photoinitiating systems, the pertinence of this approach is demonstrated.
EUROPEAN POLYMER JOURNAL
(2022)
Review
Chemistry, Physical
Frederic Dumur
Summary: Photopolymerization uses light as the activation source to convert liquid monomers to polymers. The development of visible light photo-initiating systems and the search for new dyes that can polymerize a resin within seconds are ongoing. Quinoxaline has been identified as a promising scaffold for designing UV-centered and visible light photo-initiating systems. This review provides an overview of different quinoxaline-based dyes and compares them with reference systems to demonstrate their significance.
Article
Polymer Science
Frederic Dumur
Summary: Photopolymerization under visible light has made significant progress in recent years, thanks to the development of new irradiation setups based on LEDs. Efficient photoinitiating systems that match the light sources used in 3D printers have become increasingly important. However, visible light photoinitiators, although they increase the thickness of the polymerized films, are often strongly colored compounds that hinder the use of photopolymers for everyday applications. To tackle this issue, the development of photobleachable photoinitiating systems has emerged as a promising research field. This review provides an overview of recent advances in photobleachable photoinitiators and discusses the exploration of various structures to address the challenge of achieving colorless coatings.
EUROPEAN POLYMER JOURNAL
(2023)
Article
Polymer Science
Frederic Dumur
Summary: Visible light photoinitiators that can operate under low light intensity are actively researched to address safety concerns and high energy consumption issues associated with traditional UV photoinitiators. Among these, indane-1,3-dione has been identified as a promising scaffold for design of various structures in this last generation of photoinitiators. Comparisons with reference compounds are provided to evaluate the performance of these photoinitiators.
EUROPEAN POLYMER JOURNAL
(2021)
Article
Engineering, Chemical
Di Zhu, Pawel Wagner, Pu Xiao
Summary: Terthiophene derivatives were prepared and used as photoinitiators for photopolymerization reactions under LED irradiation. The photochemical mechanisms, initiation ability, and applications in various polymerization reactions were investigated. Particularly, a sodium salt form of a terthiophene derivative showed exceptional water solubility and efficiency in hydrogel formation, while the storage stability of the effective photoinitiating systems in formulations was also studied.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2021)
Article
Polymer Science
Loic Buchon, Jean-Michel Becht, Laurent Rubatat, Wei Wang, Hua Wei, Pu Xiao, Jacques Lalevee
Summary: This research synthesized and characterized four potential phosphine oxide photoinitiators and evaluated their efficiency in photopolymerization at 405 nm wavelength. Two of the obtained photoinitiators showed better performance than the widely used commercial photoinitiator. Additionally, one of the synthesized photoinitiators was successfully used in 3D printing of thermoplastics and exhibited lower cytotoxicity compared to the benchmark structure.
JOURNAL OF APPLIED POLYMER SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Ziying Lei, Nicole E. Olson, Yue Zhang, Yuzhi Chen, Andrew T. Lambe, Jing Zhang, Natalie J. White, Joanna M. Atkin, Mark M. Banaszak Holl, Zhenfa Zhang, Avram Gold, Jason D. Surratt, Andrew P. Ault
Summary: The reactive uptake of VOC-derived semivolatile oxidation products on inorganic-organic submicron particles was studied, and it was found that the viscosity and morphology of the particles changed significantly after the uptake. The changes were highly dependent on the VOC precursor, and the impact on air quality and climate predictions could be altered.
ACS EARTH AND SPACE CHEMISTRY
(2022)
Article
Polymer Science
Frederic Dumur
Summary: Photopolymerization under visible light has made significant progress in recent years, thanks to the development of new irradiation setups based on LEDs. Efficient photoinitiating systems that match the light sources used in 3D printers have become increasingly important. However, visible light photoinitiators, although they increase the thickness of the polymerized films, are often strongly colored compounds that hinder the use of photopolymers for everyday applications. To tackle this issue, the development of photobleachable photoinitiating systems has emerged as a promising research field. This review provides an overview of recent advances in photobleachable photoinitiators and discusses the exploration of various structures to address the challenge of achieving colorless coatings.
EUROPEAN POLYMER JOURNAL
(2023)
Article
Biochemistry & Molecular Biology
Thanh-Tuan Bui, Sebastien Peralta, Frederic Dumur
Summary: Fifteen push-pull dyes based on tetracyclic polyaromatic pyrene were synthesized and their optical properties were investigated in twenty-two solvents with different polarities. Surprisingly, contrary to conventional D-pi-A push-pull dyes, negative solvatochromism was observed in many of the dyes. Photoluminescence and thermal properties were also examined, and theoretical calculations were conducted to support the experimental findings.
Review
Polymer Science
Frederic Dumur
Summary: Anthraquinone has been identified as a promising scaffold for designing photoinitiating systems activable in the visible range and under low light intensity. Molecular engineering has allowed the development of water-soluble, panchromatic, or photobleachable dyes based on this scaffold. This review provides an overview of recent advances in photopolymerization using anthraquinone-based photoinitiating systems.
EUROPEAN POLYMER JOURNAL
(2023)
Article
Polymer Science
Marie Le Dot, Nicolas Giacoletto, Fabrice Morlet-Savary, Bernadette Graff, Valerie Monnier, Didier Gigmes, Malek Nechab, Frederic Dumur, Pierre Gerard, Jacques Lalevee
Summary: A new configuration of Metal Acetylacetonate Bidentate Ligand Interaction (MABLI) mechanism has been discovered for initiating the polymerization of recyclable Elium (R) thermoplastic resins under mild conditions. The presence of a phosphine oxide significantly reduces curing time and achieves nearly 100% conversion. Additionally, the combination of MABLI and photoactivation in a dual cure approach enhances the polymerization efficiency.
EUROPEAN POLYMER JOURNAL
(2023)
Review
Polymer Science
Frederic Dumur
Summary: Photopolymerization is a research field that aims to replace energy-consuming UV irradiation setups with energy-saving light-emitting diodes (LEDs) or even sunlight as a light source. Various dyes have been developed to efficiently promote polymerization processes under sunlight, enabling the use of photopolymerization in outdoor applications. This review provides an overview of different photoinitiating systems developed for polymerization processes under sunlight or daylight, comparing their efficiency to that of artificial light sources.
EUROPEAN POLYMER JOURNAL
(2023)
Review
Chemistry, Physical
Frederic Dumur
Summary: Photopolymerization is an active research field focused on polymerizing in greener conditions using visible light instead of traditional UV light. Furane is an interesting candidate for designing photocatalysts of polymerization due to its low cost and easy chemical modification. This review provides an overview of furane-based photoinitiator design and compares them to reference systems to demonstrate their potential in innovative structures.
Review
Chemistry, Physical
Frederic Dumur
Summary: Photopolymerization uses light as the activation source to convert liquid monomers to polymers. The development of visible light photo-initiating systems and the search for new dyes that can polymerize a resin within seconds are ongoing. Quinoxaline has been identified as a promising scaffold for designing UV-centered and visible light photo-initiating systems. This review provides an overview of different quinoxaline-based dyes and compares them with reference systems to demonstrate their significance.
Article
Polymer Science
Frederic Dumur
Summary: Photoinitiating systems activable under visible light are the subject of many studies due to their ability to achieve higher light penetration. The reactivity of these systems can be improved by investigating new dye structures, including naphthoquinones which have been underexplored as visible light photoinitiators of polymerization. Recent developments have shown promising results in designing photoinitiators with naphthoquinone, paving the way for future advancements. This review provides an overview of different photoinitiators containing a naphthoquinone unit and compares their polymerization efficiencies with reference compounds.
EUROPEAN POLYMER JOURNAL
(2023)
Review
Polymer Science
Frederic Dumur
Summary: Iodonium salts, a type of cationic photoinitiators, have a long history of use in the polymerization of epoxides or vinyl ethers. However, their UV-centered absorption restricts their use to the visible range through a photosensitization process. To simplify the composition of photopolymerizable resins, various dyes have been covalently linked to iodonium salts, resulting in monocomponent photoinitiating systems. This review provides an overview of the different dyes connected to iodonium salts.
EUROPEAN POLYMER JOURNAL
(2023)
Article
Polymer Science
Frederic Dumur
Summary: Photopolymerization is undergoing a revolution with the emergence of affordable and easily accessible LEDs, making polymerization possible under safe and energy-saving conditions. Bodipys, which are renowned for their high photoluminescence quantum yields, exceptional molar extinction coefficients, and narrow absorption and emission bands, have been identified as a promising platform for designing photoinitiators. Recent advancements in difluoroborane derivatives, such as boranils, squaraine-derived structures, and 2-phenacylbenzoxazole difluoroboranes, have expanded the application scope of photopolymerization. This review presents the various bodipys, boranils, squaraine-based difluoroborate complexes, and 2-phenacylbenzoxazole difluoroboranes used in developing photoinitiating systems and compares their efficiency to reference photoinitiating systems.
EUROPEAN POLYMER JOURNAL
(2023)
Review
Polymer Science
Frederic Dumur
Summary: In recent years, research efforts have focused on multicomponent photoinitiating systems, especially for the design of visible light photoinitiating systems. Monocomponent Type II photoinitiators have been designed to simplify the elaboration of photocurable resins. Sulfonium salts, as remarkable photoinitiators, lack absorption in the visible range, leading to various structural modifications for redshifting their absorptions. This work provides an overview of different sulfonium salts activable under visible light.
Article
Chemistry, Multidisciplinary
Yijun Zhang, Zheng Liu, Timur Borjigin, Bernadette Graff, Fabrice Morlet-Savary, Michael Schmitt, Didier Gigmes, Frederic Dumur, Jacques Lalevee
Summary: Seventeen carbazole-fused coumarin-based oxime esters were developed as efficient and visible light-absorbing initiators for polymerization. Certain oxime esters exhibited comparable or better photoinitiation performance than the benchmark photoinitiator under LED irradiation. These oxime esters also showed thermal initiation behavior and could be used as both thermal and photo-initiators. Moreover, two oxime esters, OXE-1 and OXE-5, were found to be sunlight activable and achieved high monomer conversion rates within one hour.
Article
Chemistry, Physical
Nataliya Kalashnyk, Adam Hassan Denawi, Frederic Dumur, Didier Gigmes, Xavier Bouju, Sylvain Clair
Summary: The supramolecular self-assembly of s-indacene-1,3,5,7(2H,6H)-tetrone on the Cu(111) surface was investigated and six different phases were found, driven by different interactions. Host-guest interactions allowed for the accommodation of molecular or metal clusters inside the nanoporous patterns. Three metal-organic networks led to the creation of regular arrays of isolated metal adatoms or adatom clusters.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
