Visible light photopolymerization employing 2,4-diiodo-6-butoxy-3-fluorone and tetraorganylborate salts as photoinitiators

Abstract

Several new tetraorganylborate salts have been synthesized and tested as coinitiators with 2,4‐diiodo‐6‐butoxy‐3‐fluorone (DIBF) for the photopolymerization of acrylic monomer mixtures. The rate of photopolymerization has been found to be a function of chemical structure of the borates. Stability, solubility, and reactivity of these borates as coinitiators for photopolymerization have been investigated. Diphenyldialkylborates have been found to be the best among the tested coinitiators. © 1996 John Wiley & Sons, Inc.

Factors affecting the TMPTA radical polymerization photoinitiated by phenyltrialkylborates paired with tri-cationic hemicyanine dye. Kinetic studies

“…Phenyltrialkylborate tetramethylammonium salts listed in Scheme 1 were prepared in my laboratory with modified methods described by Neckers et al [11, 12]. The detailed synthetic procedures as well as the basis of analytical results and spectral evidences of the tetramethylammonium phenyltrialkylborates the readers can find in my previous paper [13].…”

Photochemical Study of a Three‐Component Photocyclic Initiating System for Free Radical Photopolymerization: Implementing a Model for Digital Light Processing 3D Printing

“…(Figure S2). During this process, the borate anion is oxidized to form a tetraphenylboryl radical that then undergoes carbon‐boron bond cleavage and generates a free phenyl radical …”

New Squaraine‐based two‐component initiation systems for UV‐blue light induced radical polymerization: Kinetic and time‐resolved laser spectroscopy studies

“…Tetraorganylborate salts may be oxidized by several photoexcited oxidizing agents to release free radicals that may be used to initiate chain polymerization . There are many examples of two‐component photoinitiating systems working through electron transfer process composed of organic borate salts.…”

“…In one of proposed mechanism, the iodonium salt and photosensitizer undergo bimolecular reaction via electron transfer from dye molecule, to form a dye‐based radical cation and diphenyliodonium radical . This reaction generally involves electron transfer from the photoexcited triplet state of dye to the iodonium cation, followed by rapid decomposition of iodonium radical . The onium radical formed fragments on iodobenzene and phenyl radical.…”