High refractive index silicone nanocomposites
The present disclosure provides nanocrystals(s) containing silicone capping agent(s). Dispersions containing the nanocrystal(s) and at least one of silicone monomer(s), silicone pre-polymer(s), and silicone polymer(s), and optionally additionally containing a solvent are also described. Cured dispersions, compositions of nanocrystal(s) and LEDs and related structures containing the composition(s) are provided in the present disclosure.
1. A dispersion comprising:
(i) nanocrystals,
(ii) at least one of silicone monomer(s), silicone pre-polymer(s), and silicone polymer(s), and
(iii) a solvent, wherein
the nanocrystals are dually capped with at least two different capping agents and comprise metal oxides selected from zirconium oxide, titanium oxide, hafnium oxide, zinc oxide, yttrium oxide, and niobium oxide and mixtures and alloys thereof;
the capping agents comprising a head group and at least one tail group;
the head group comprising a trialkoxysilane group, a trichlorosilane group, a dialkoxysilane group, a dichlorosilane group, an alkoxysilane group, or a chlorosilane group, and the head group is a group which reacts with the hydroxide (—OH) or —OR (R=alkyl or aryl) groups present at the surface of the metal oxides of the nanocrystal to form a covalent linkage;
the tail group is a functionalized or non-functionalized silicone chain or hydro-carbon chain as shown below:
wherein each of R 1 , R 2 , R 3 , R 4 is selected from H, alkyl groups, aryl groups, and polyaryl groups,
the b and c are independently from 0 to 60 while b and c cannot both be zero,
R 0 is (CH 2 ) a and connects to the head group,
R 5 is Si(CH 3 ) 3 , Si(CH 3 ) 2 H, Si(CH 3 ) 2 (CHCH 2 ), or Si(CH 3 ) 2 (C 4 H 9 ),
R′ is —H or alkyl group,
R′ is —H, alkyl group, alkenyl group, or alkynyl group, and
a is 2 to 18,
with the provision that the tail group of the first capping agent is a non-functionalized or functionalized silicone chain, and the tail group of the second capping agent is a non-functionalized silicone chain or the non-functionalized or functionalized hydro-carbon chain, and wherein
the dispersion has a transparency of 20-99% at 400 nm when a sample of the dispersion having a 50 weight % loading of the nanocrystals is measured with a UV-Vis spectrophotometer with 1 cm optical path cuvette.
2. The dispersion of claim 1 wherein the dispersion has a transparency of 30-99% at 400 nm when a sample of the dispersion having a 50 weight % loading of the nanocrystals is measured with a UV-Vis spectrophotometer with 1 cm optical path cuvette.
3. The dispersion of claim 1 wherein the dispersion has a transparency of 40-99% at 400 nm when a sample of the dispersion having a 50 weight % loading of the nanocrystals is measured with a UV-Vis spectrophotometer with 1 cm optical path cuvette.
4. The dispersion of claim 1 wherein the dispersion has a transparency of 50-99% at 400 nm when a sample of the dispersion having a 50 weight % loading of the nanocrystals is measured with a UV-Vis spectrophotometer with 1 cm optical path cuvette.
5. The dispersion of claim 1 wherein the dispersion has a transparency of 60-99% at 400 nm when a sample of the dispersion having a 50 weight % loading of the nanocrystals is measured with a UV-Vis spectrophotometer with 1 cm optical path cuvette.
6. A cured film of the dispersion of claim 1 which has an increase in refractive index of at least 0.05 as compared to the refractive index of a cured material of the dispersion without the nanocrystals.
7. The cured film of claim 1 which has an increase in refractive index of at least 0.10 as compared to the refractive index of a cured material of the dispersion without the nanocrystals.
8. A cured nanocomposite film of the dispersion of claim 1 .
9. A light emitting diode (LED) comprising the cured nanocomposite film of claim 8 .
10. An organic light emitting diode (OLED) comprising the cured nanocomposite film of claim 8 .