Visible light photoinitiating system for preparing high diffraction efficiency hologram optical polymer material

US9753431B2 · kind B2 · utility

Assignee

• Huazhong University of Science and Technology · CN

Inventors

• Xiaolin Xie · Xi'an, CN
• Haiyan Peng · Hubei, CN
• Xingping Zhou · Hubei, CN
• Chengfu Zheng · 红钢城街道, CN
• Hongwei Ge · 红钢城街道, CN

Key dates

• Filing date: May 25, 2012
• Grant date: Sep 5, 2017
• Expiry date: Oct 22, 2032

Classification

• Technology area (CPC G): Physics
• CPC primary: G03H2260/12
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

The present invention provides a visible light photoinitiating system for preparing a holographic photopolymer material with high-diffraction efficiency. The photoinitiating system comprises a photosensitizer and a co-initiator, and its mechanism is that the photosensitizer transforms from ground state to excited state after absorbing photons, and then interacts with the co-initiator through transfer of electrons and protons, which produces an alkyl (or aryl) free radical R and a ketyl radical K; wherein the free radical R initiates the addition polymerization of monomers that are capable of free radical polymerization, whereas the radical K inhibits the chain propagation of the macromolecular free radicals to a certain degree due to the steric hindrance effect, and thus delays the gelation time of the photopolymerization, which helps to increase the phase separation between the polymer and the functional components. A holographic photopolymer material with high-diffraction efficiency can be obtained by employing this visible light photoinitiating system.