Thermal effects of the functionalities of chain transfer agent on photopolymer holographic volume gratings

Abstract

The photopolymerizable nanoparticle-polymer composites (NPCs) have thus far shown their excellent performance in practical applications, such as holographic data storage, nonlinear optics and neutron optics. We have demonstrated twofold enhancement of the saturated refractive index modulation (Δn sat ) of ZrO 2 NPC volume gratings recorded at high spatial frequencies by doping with a single functional thiol as a chain transfer agent (CTA). This result suggested that the incorporation of a CTA in an NPC is very useful for holographic applications of volume gratings in light and neutron optics. Such chemical modification of NPC volume gratings may be more effective by doping with multifunctional thiols. This is so because polymer features such as the molecular weight and the crosslinking network density can be tailored more diversely by introducing multifunctional thiols in photopolymers. The influences of varying functionalities of thiols as chain transfer agents on the thermal stability of a volume grating recorded in a photopolymerizable ZrO 2 nanoparticle-polymer composite film have been investigated.