Preparation of High Refractive Index Zirconium Dioxide / Silicone Resin Composite Materials and Its Application on LED Encapsulating Materials
Date Issued
2012
Date
2012
Author(s)
Lai, Dai-Fu
Abstract
The research was divided into two parts. Zirconium dioxide (ZrO2) nanoparticles with high refractive index were introduced into commercial-grade silicone resin by an in-situ sol gel reaction in the first part. The acetic acid was used as chelating agent to control the particle size of ZrO2 and modified the surface of ZrO2 to provide linkages between the water phase of ZrO2 and the oil phase of silicone resins. Moreover, butanol and methyl ethyl ketone were chosen as the co-solvent system to prevent ZrO2 particles from aggregation during the sol-gel process.
Then we synthesized optical films with high refractive index and high transmittance and synthesized composite films with high refractive index thin film on the bottom and encapsulating material on the top of the composite film. Through using the encapsulating materials with decreasing refractive index layer-by-layer, LEDs could achieve higher light extraction efficiency. In order to achieve the requirements of LED encapsulating materials, optical thin films and composite films were synthesized and measured in terms of refractive index, transmittance, water uptake, thermal resistance and UV resistance.
The curing degree of the silicone resin after introducing zirconium dioxide nanoparticles was investigated in the second part. The influences of the concentration and the size domain of the zirconium dioxide on the degree of curing degree was studied by DSC measurement, and the curing degree of the composite film was investigated by DSC measurement as well.
Subjects
zirconium dioxide (ZrO2)
sol-gel method
LED encapsulating materials
high refractive index
organic/inorganic hybrid materials
Type
thesis
File(s)![Thumbnail Image]()
Loading...
Name
ntu-101-R99524014-1.pdf
Size
23.54 KB
Format
Adobe PDF
Checksum
(MD5):77b12c6c00af1d58252e692b53155c99