Preparation of polymer nanocomposites with “ultrahigh” refractive index

Abstract

Nanocomposites of lead sulfide and several polymers, especially poly(efhyleneoxide), were prepared by coprecipitation of lead sulfide and polymer, followed by a drying and pressing procedure. Such nanocomposites consist of ca. 90% w / w (or ca. 50% v / v ) lead sulfide, of particle dimensions of 2-40 nm. The refractive index of these materials is on the order of 3 and therefore, to the authors' best knowledge, is the highest reported for any polymer composite.

High Refractive Index Materials of Iron Sulfides and Poly(ethylene oxide)

“…As far as we know, only the refractive indices of PEO-PbS composites (around 3) 4 have been reported to be higher than those of the highest refractive index composites prepared here. The PEO-PbS composites contain ca.…”

“…Materials with refractive indices of 2.5 -2.8 (at least at 1295 nm) were prepared with Mohr's salt which seems to be more favorable for the preparation of high refractive index materials than FeCl 2 or FeSO 4 . This might be due to the presence of the ammonium ions in Mohr's salt.…”

“…2. All the samples prepared from FeSO 4 and FeCl 2 contained, among other components, also crystalline sulfur (see Table I); in addition, the samples prepared from FeSO 4 contained pyrite. After 311 h, all the samples showed the color of rust, indicating that a large fraction of the iron sulfides had decomposed to iron oxides.…”

“…Nanocomposites with extremely high or low refractive index have been prepared recently by coprecipitation or spin-coating from aqueous solutions. [4][5][6][7] The high refractive index nanocomposites consist of colloidal lead sulfide embedded in a polymer matrix. Due to the high refractive index of PbS, that of the composites is up to 3, over a broad wavelength range, and to our knowledge by far the highest reported for a polymer composite.…”

Exploration on structural morphology and properties of novel poly(urethane-imide)/TiO2 bionanocomposites derived from L-tyrosine based diol

“…Since the refractive index of the polymers is usually in the range of 1.3-1.7, the application of polymers as high refractive index materials is limited [15][16][17][18][19]. Lately, the preparation of inorganic/organic hybrid materials with high refractive index has attracted substantial interest [20][21][22][23][24][25][26][27][28]. A technique for producing high refractive index nanocomposites and transparency in the fields of clear coatings, optical waveguides, and anti-reflection coatings for optical components was developed by incorporating premade inorganic colloidal particles into a polymer matrix.…”