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Phenacyl bromide has been explored as a new Norrish Type I photoinitiator for radically polymerizing methyl methacrylate and styrene monomers. A straightforward radical photopolymerization method using UVA light for the synthesis of chain-end functional poly(methyl methacrylate) and polystyrene has been developed. The process has been refined for both bulk and solution photopolymerizations. Chain-end functionalization was demonstrated by the formation of block-copolymers of the bromine-ended homopolymers, utilized as macroinitiators, resulting in an increase in the molecular weight of the corresponding precursor, observed by gel permeation chromatography (GPC). Block copolymerization was initiated by radicals generated at the chain-ends by a halogen-atom transfer reagent, namely, dimanganese decacarbonyl (Mn2(CO)10). This simple light-induced method is promising for the additive manufacturing field such as vat photopolymerization, stereolithography, digital light processing as it yields chain-end functional materials that can be further processed. Table of Contents (TOC). [ABSTRACT FROM AUTHOR]

A straightforward approach is employed to synthesize methylene‐bridged poly(hetero aromatic)s based on furan, pyrrole, thiophene, and thiophene derivatives. The process involves an electrophilic aromatic substitution reaction facilitated by a visible light‐initiated system consisting of manganese decacarbonyl and an iodonium salt. The approach mainly relies on the formation of halomethylium cation, the attack of this cation to heteroaromatic, regeneration of methylium cation on the heteroaromatic, and reactivity differences between halomethylium and heteroaromatic methylium cations for successful polymerizations. This innovative synthetic strategy lead to the formation of polymers with relatively high molecular weights as the stoichiometric imbalance between the comonomers increased. Accordingly, these newly obtained polymers exhibit remarkable fluorescence properties, even at excitation wavelengths as low as 330 nm. Moreover, by harnessing the halogens at chain ends of homopolymers, block copolymers are successfully synthesized, offering opportunities for tailored applications in diverse fields. [ABSTRACT FROM AUTHOR]

3D printing technology offers solutions for numerous needs in industry and the daily life of individuals. In recent years, most research efforts have focused on this technology as the market share has grown and requirements have become specified in their related fields. In this work, a novel visible light induced 3D printing system with high resolution and short printing time using dimanganese decacarbonyl (Mn2(CO)10) in combination with organic halides is reported. The radicals formed through halogen abstraction by photochemically generated manganese pentacarbonyl from organic halides with high quantum efficiency initiate the polymerization of acrylic resins. The kinetics of the process using various halide‐containing molecules in the photoinitiaiting system are investigated with real‐time fourrier transform infrared spectroscopy and photo‐differential scanning calorimetry analyses, and the characteristics of 3D printouts are presented and compared with that of the commercial photoinitiator, 2,4,6‐trimethylbenzoyl)phosphine oxide without Mn2(CO)10. The results obtained confirm that the combination of Mn2(CO)10 and structurally diverse organic halides is a class of promising 3D system for various applications. [ABSTRACT FROM AUTHOR]

In this work, photoinduced thiol‐epoxy click reaction for side‐chain functionalization, chain‐extension, grafting, and cross‐linking of polymers prepared by atom transfer radical polymerization by using 1,5‐diazabicyclo[5.4.0]undec‐5‐ene thioxanthone acetate (Tx‐DBU) as a photo base generator (PBG) is described. Irradiation of Tx‐DBU at 365 nm leads to the generation of 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) in neutral form as a super base. DBU is capable of abstracting protons from thiols and thus formed thiolates are excellent nucleophiles that exhibit high affinity toward electrophiles such as epoxide rings. Appropriately selected thiols are successfully used for the desired reactions. The precursors and resulting polymers are characterized using 1H‐NMR, Fourier transform infrared, gel permeation chromatography, and differential scanning calorimetry measurements. This study shows that the use PBGs can further be extended to the synthesis of various complex macromolecular structures by the described post modification processes. [ABSTRACT FROM AUTHOR]