Controlled Photopolymerization and Novel Architectures

Doran, Seán; Taşkın, Ömer Suat; Taşdelen, Mehmet Atilla; Yaǧcı, Yusuf

doi:10.1002/9781119006671.ch3

Cited by 18 publications

(10 citation statements)

References 146 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Type I photoinitiators, especially α-hydroxyketones and acylphosphine derivatives, are widely used in industry for coatings’ forms [ 33 , 34 ], although initiatorless photopolymerization processes are also realized as well [ 35 ]. Nevertheless, current research is focusing on new photoinitiators in photopolymerization processes of acrylates, i.e., bis-silyl ketone [ 36 ] or novel phosphine oxides [ 37 , 38 ].…”

Section: Introductionmentioning

confidence: 99%

Free-Radical Bulk-Photopolymerization Process as a Method of Obtaining Thermally Curable Structural Self-Adhesive Tapes and Effect of Used Type I Photoinitiators

2020

View full text Add to dashboard Cite

A new fabrication method for thin (120 µm) thermally curable structural self-adhesive tapes (SATs) was demonstrated by utilizing a series of acrylic syrups (ASs) modified using Bisphenol A-based liquid epoxy resin. The acrylic syrups containing poly(butyl acrylate-co-butyl methacrylate-co-glycidyl methacrylate-co-2-hydroxyetyl acrylate-co-4-acryloyloxy benzophenone) were synthesized via free-radical bulk-photopolymerization (FRBP) process. Influence of different type I radical photoinitiators (PIs), i.e., α-hydroxyalkylphenones (HPs), acylphosphine oxides (APOs) and its mixtures (HPs/APOs and APO/APO) on selected physico-chemical features of obtained ASs was studied. It turned out that APO-type PIs are more effective in the FRBP process (NMR studies). Self-adhesive tests of SATs revealed that the monomers’ conversion in ASs have a significant influence on adhesion and tack. Moreover, the polymer structures formed at the UV cross-linking stage of SATs significantly affect the cross-linking degree of SATs during thermal curing (differential scanning calorimetry method). The highest values of overlap shear strength were achieved by SATs based on ASs with monomers’ conversion on the level 50–60%.

show abstract

Section: Introductionmentioning

confidence: 99%

Free-Radical Bulk-Photopolymerization Process as a Method of Obtaining Thermally Curable Structural Self-Adhesive Tapes and Effect of Used Type I Photoinitiators

2020

View full text Add to dashboard Cite

show abstract

“…[173] Besides, this result is counterintuitive considering that the photopolymerization process can be carried out at room temperature so that a higher control could be expected by avoiding the presence of sidereactions. [20,[174][175][176][177][178][179][180][181][182][183][184][185] To address this issue, control agents have been developed, as exemplified with the photoassisted nitroxide mediated polymerization (NMP2 or Photo-NMP), where a photosensitive alkoxyamine can be used. [174,186] As a result of a convenient substitution of the initial alkoxyamine, the dormant species can be activated "on demand", enabling to reinitiate the polymerization process.…”

Section: Iron-based Complexesmentioning

confidence: 99%

Recent advances on iron-based photoinitiators of polymerization

Dumur

2020

European Polymer Journal

View full text Add to dashboard Cite

With regards to the environmental and safety concerns raised nowadays by the polymer industry, polymerization processes requiring light as the activation source are currently knowing a revival of interest after decades of disinterest. Recent progresses in photopolymerization are notably sustained by the development of new polymerization application namely 3D and 4D printing enabling an unprecedented access to structures of incredible complexity. Parallel to the manufacturing process, the polymer material itself and its composition are also facing numerous questions concerning their environmental and human health impacts. Beyond the monomers, the different additives introduced in the resin can also be potentially toxic so that a great deal of efforts is currently done to develop new photoinitiators with a toxicity assessed as being insignificant. In this field, iron-based metal complexes are candidates of choice due to the clinical demonstration of their very low toxicities. Among iron complexes, ferrocene is among the most widely studied iron-based metallocene. Due to its unique and reversible electrochemical properties as well as their absorption centred in the visible range, numerous photoinitiators have been developed with ferrocene or its oxidized form i.e. ferrocenium. Parallel to this, the remarkable electrochemical properties of ferrocenium made it an excellent candidate for its incorporation in photoinitiating systems. However, interest for iron-based photoinitiators was not limited to ferrocene and ferrocenium, and Schiff base complexes were also successfully used as initiators of polymerization. In this review, an overview of the different iron-based photoinitiating systems reported to date is presented. More precisely, if iron-based photoinitiators are developed since 50 years, a special focus will be done on photoinitiators designed for recent polymerization conditions, namely, under visible light and low light intensity.

show abstract

“…This result is counterintuitive since, from a theoretical point of view, a higher control of the polymerization process should be obtained by using light, when the polymerization reaction is carried out at room temperature. In these conditions, the competition between polymerization and side-reactions should be avoided [126][127][128][129][130][131][132][133][134][135][136]. However, the production of highly reactive radicals still limits the control of the polymerization process, even if some attempts have been made to introduce control agents, as exemplified with photoassisted nitroxide-mediated polymerization (NMP2) [124,125].…”

Section: Iron Complexesmentioning

confidence: 99%

Recent Advances on Visible Light Metal-Based Photocatalysts for Polymerization under Low Light Intensity

Dumur

2019

Catalysts

View full text Add to dashboard Cite

In recent years, polymerization processes activated by light have attracted a great deal of interest due to the wide range of applications in which this polymerization technique is involved. Parallel to the traditional industrial applications ranging from inks, adhesives, and coatings, the development of high-tech applications such as nanotechnology and 3D-printing have given a revival of interest to this polymerization technique known for decades. To initiate a photochemical polymerization, the key element is the molecule capable to interact with light, i.e., the photoinitiator and more generally the photoinitiating system, as a combination of several components is often required to create the reactive species responsible for the polymerization process. With the aim of reducing the photoinitiator content while optimizing the polymerization yield and/or the polymerization speed, photocatalytic systems have been developed, enabling the photosensitizer to be regenerated during the polymerization process. In this review, an overview of the photocatalytic systems developed for polymerizations carried out under a low light intensity and visible light is provided. Over the years, a wide range of organometallic photocatalysts has been proposed, addressing both the polymerization efficiency and/or the toxicity, as well as environmental issues.

show abstract

Controlled Photopolymerization and Novel Architectures

Cited by 18 publications

References 146 publications

Free-Radical Bulk-Photopolymerization Process as a Method of Obtaining Thermally Curable Structural Self-Adhesive Tapes and Effect of Used Type I Photoinitiators

Free-Radical Bulk-Photopolymerization Process as a Method of Obtaining Thermally Curable Structural Self-Adhesive Tapes and Effect of Used Type I Photoinitiators

Recent advances on iron-based photoinitiators of polymerization

Recent Advances on Visible Light Metal-Based Photocatalysts for Polymerization under Low Light Intensity

Contact Info

Product

Resources

About