Stoichiometric thiol-ene ratio dependence of refractive index modulation and polymerization shrinkage in holographic nanocomposite materials

Abstract

We report on volume holographic recording in photopolymerizble nanocomposite materials using inorganic SiO 2 nanoparticles dispersed in thiol-ene monomers capable of stepgrowth photopolymerization with various stoichiometric thiol-ene ratios. It is shown that while the refractive index modulation is maximized at the stoichiometric composition, polymerization shrinkage decreases with increasing the thiol monomer fraction.