1‐Aryl‐2‐(triisopropylsilyl)ethane‐1,2‐diones: Toward a New Class of Visible Type I Photoinitiators for Free Radical Polymerization of Methacrylates

1‐Aryl‐2‐(triisopropylsilyl)ethane‐1,2‐diones (SEDs) are proposed here as a new class of visible Type I photoinitiators (PIs) for free radical polymerization under air upon exposure to blue (@455 nm) and green (@520 nm) LEDs. Remarkably, these new systems present good polymerization performances and excellent bleaching properties compared to camphorquinone‐based systems, and transparent polymers are obtained upon visible light irradiation. Real‐time Fourier transform infrared spectroscopy is used to monitor the polymerization profiles. Molecular orbital calculations are also carried out for a better understanding of the structure/reactivity relationship of the photoinitiators. 1‐Aryl‐2‐(triisopropylsilyl)ethane‐1,2‐diones are presented here as a new class of visible Type I photoinitiators for free radical polymerization. These new systems present good polymerization performances and excellent bleaching properties compared to camphorquinone‐based systems, and transparent polymers are obtained upon visible‐light irradiation. The chemical mechanisms are also presented for a better understanding of their reactivity.