Synthesis and characterization of high refractive index nanoparticle/poly(arylene ether ketone) nanocomposites

This paper presents a successful synthesis of transparent organic-inorganic nanocomposites from poly(arylene ether ketone) (PAEK)-based matrix polymer and BaTiO(3) nanoparticles. The dispersibility of nanoparticles was significantly improved by both the introduction of phosphonic acid moiety into the polymer chain and the organic modification of the nanoparticle surface. The structure of phosphonic-acid-modified PAEK polymer was studied by gel permeation chromatography, (31)P nuclear magnetic resonance spectroscopy and X-ray fluorescence spectroscopy. Thermal properties of nanocomposites were studied by thermogravimetry and differential scanning calorimetry. Optical clarity of nanocomposites was evaluated by a hazemeter and regular transmittance spectroscopy. Dispersion of nanoparticles was also demonstrated by transmission electron microscopic observation. Fourier transform infrared analysis was carried out to investigate the interaction between the polymer matrix and nanoparticles. Refractive indices of the obtained transparent nanocomposites, which contain up to 44.1 wt% of nanoparticles, were measured. A high refractive index of 1.72 at 589 nm was achieved. Polymer Journal (2010) 42, 179-184; doi:10.1038/pj.2009.322; published online 23 December 2009