Waveguide fabrication in UV-photocurable sol–gel materials: Influence of the photoinitiating system

Abstract

In this paper we identify and explain the different chemical interactions involved between a sol-gel matrix and photoinitiators used in the fabrication of optical waveguides. A well-established sol-gel matrix composed of 3-methacryloxypropyltrimethoxysilane, zirconium n-propoxide and methacrylic acid was developed, and two different photoinitiators (Irgacure® 819 and 1800) were added to the host matrix. Optical microscopy was used to characterise the structure of the waveguides as a function of the photoinitiator nature and concentration, and aging of the hybrid sol-gel material. It is clearly demonstrated that the width of the waveguides is strongly influenced by the sol aging. Furthermore, it is shown that degradation of photoinitiators occurs during the sol-gel process. Oxidation of the phosphonyl groups by the zirconium complex accounts for this results.

Synthesis of Organosilica Films Through Consecutive Sol/Gel Process and Cationic Photopolymerization

“…Among the various photopolymer nanocomposites released recently, much attention has been given to the potentialities offered by hybrid sol/gel photomaterials. Their unique combination of properties makes these novel nanocomposites particularly attractive in optoelectronics [2][3][4][5] and coating chemistry. [6][7][8][9] Organoalkoxysilane precursors with the general formula R'Si(OR) 3 proved to be remarkably well-suited as molecular starting blocks in the synthesis of hybrid sol/gels.…”

Influence of hybrid organic–inorganic sol–gel matrices on the photophysics of amino-functionalized UV-sensitizers

“…Fabrication of 2D microstructures is generally performed using the single-photon polymerization technique, which utilizes the linear optical absorption of UV-sensitive photoinitiators to cause the photoinduced crosslinking of organic molecules [12]. The fabrication of 3D microstructures has become possible with the recent development of the 2PP technique [2,4,13,14], which exploits the multiphoton absorption of materials that are primarily UV-sensitive.…”

Formation of molecular doping patterns in organic–inorganic hybrid films by a capillary electrophoresis doping technique

“…The employed heating conditions are chosen to allow the migration of R6G molecules only when the electric field assists the doping. The addition of the photoinitiator IRGACURE184 effectively initiates the radical polymerization between the -C C-bonds via UV irradiation and induces a chain reaction [14][15][16][17]. Using this characteristic reaction, the photolithography patterning of hybrid materials for the optical devices has been investigated.…”