Template-Free Fabrication of Refractive Index Tunable Polysiloxane Coating Using Homogeneous Embedding Strategy: Application in High-Power Laser System

Abstract

A refractive index (RI) tunable polysiloxane coating was fabricated based on the cross-linked network structure embedded with mesoporous silica nanoparticles (MSNs), in which the MSNs were utilized to modulate the RI as well as to support the interior structure of the polysiloxane coating. The Si–O–Si inorganic backbone structure in combination with characteristics from the photopolymerization of active bonds produced the main cross-linked network structure, and controllable embedding of MSNs constructed the network-sphere structure. This approach eliminated the high-temperature post-treatment that was needed to remove the template, which ensures the safe application for temperature-sensitive laser crystal substrates and avoids coating structure collapse. In addition, degradation of the resulting coating can be minimized due to the similar chemical formation between MSN and polysiloxane coating. Hereby, a polysiloxane coating with expected spectral and laser damage-resistant properties can be obtained. This will facilitate the fabrication and application of a laser component with both high-transmission and high-flux capability for a high-power laser system.

Fabrication of UV-Curable Polysiloxane Coating with Tunable Refractive Index Based on Controllable Hydrolysis

“…The preparation of porous SiO 2 nanoparticles has been described in our previous work [14]. There are two main usage of porous SiO 2 nanoparticle regarding the application: (1) The refractive index of a polysiloxane coating can be accurately modulated by embedding porous SiO 2 nanoparticles.…”

“…The sol–gel technique is a favorable method for preparing such coatings due to its advantages, like its low cost, high chemical purity, high preparation efficiency, and strong resistance to laser damage [ 6 , 7 , 8 ], compared with other methods [ 9 , 10 , 11 ]. However, sol–gel-prepared polysiloxane coatings need to be cured at 140 °C (which is higher than the phase transition temperature of DKDP crystal [ 12 ]), and its intrinsic refractive index is higher (around 1.5 [ 13 , 14 ]) than the designed value (around 1.37) to achieve high transmission at both 1053 nm and 527 nm.…”

The Preparation of a novel moisture-curing silicone conformal coating

“…Polysiloxanes have found extensive application in aerospace, electronic devices, and biomedical sectors owing to their bioinert characteristics, flexibility, and insulation capabilities [6][7][8]. The side chains of polysiloxanes impart distinctive characteristics, including superior hydrophobicity, thermal stability, and high refractive index [9][10][11]. Moisture-curing silicone conformal coatings with low refractive index typically utilize α, ωdihydroxy polydimethylsiloxane polymers that undergo crosslinking with a crosslinker in the presence of a curing catalyst at room temperature, leading to the completion of cross-linking and curing [12,13].…”

Fabrication and investigation of multifunctional fluorinated polysiloxane coatings with phenyl as bridging group

“…Polysiloxanes with Si O Si as the main chain are useful materials because they possess such functionalities as high thermal stability, electrical resistance, low-dielectric constant, and hydrophobicity. [1][2][3][4][5] Fluorinated polysiloxane is one of the most widely used polysiloxanes, which can be obtained by introducing fluoroalkyls on the side-chain of polysiloxanes. [6][7][8] To date, three types of synthetic methods for fluorinated polysiloxanes have been used: (1) the hydrolytic condensation of fluorocarbon functional silanes, (2) the ring-opening polymerization of cyclic siloxanes containing fluoroalkyl substituents, (3) the hydrosilylation of fluorinated olefins.…”

“…Polysiloxanes with SiOSi as the main chain are useful materials because they possess such functionalities as high thermal stability, electrical resistance, low‐dielectric constant, and hydrophobicity 1–5 . Fluorinated polysiloxane is one of the most widely used polysiloxanes, which can be obtained by introducing fluoroalkyls on the side‐chain of polysiloxanes 6–8 .…”